Yard and Garden: July 28, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for July 28, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and this will be the final episode from the show for 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Kevin Christiansen and Evan Alderman, Agribusiness Instructors from Southeast Community College in Beatrice

If you enjoy reading my Q&A from the show each week, take my quick survey at: http://go.unl.edu/44qr and be entered to win a free plant book or some free UNL gifts. This Survey will Close on August 18th.

1.The first caller of the day wants to know if they can still treat for bagworms that were missed with the first application?

A. If the bag is less than 1 inch in length, insecticide applications will still be effective. However, if the bags are larger than 1 inch in length, the insecticides will not work very well. Because this tree has already been sprayed this year and still has bags, I would remind everyone to ensure that they spray efficiently and according to the label, leaving areas untreated can lead to more resistance if those bagworms contacted a small concentration of the chemicals that didn’t kill them.

2. This caller called to ask me what was the best insecticide to spray for bagworms, since I left that out on the first call?

A. Tempo or Bt would be most effective. Bt is the safer alternative because it won’t harm a lot of pollinators as it just targets insects in the Lepidopteran family of insects which includes butterflies, skippers, and moths.

3. A caller has a redbud tree that blew over in a storm this spring. The roots of this tree have begun to grow some suckers. Can one of those suckers be cared for to grow into another redbud tree?

A. Yes, the suckers can be trained into a new tree. It would help the growth of the one you choose to grow if you leave the other suckers for a while as well. All of the suckers will provide energy and food to the roots, so leaving extras for a while will help. Once the main stem gets growing, you can remove the others to push the one upright.

This caller also wanted to know if he can prune his magnolia tree so he can mow under it?

A. As long as the branches are not more than half the size of the trunk and as long as you aren’t removing more than a quarter of the overall canopy the branches may be removed. The best time to prune a magnolia tree is just after it blooms in the spring, pruning now will cut off flower buds that have already developed for next spring. If the branches that would need to be removed for mowing are too large, it might be wise to change the turf to shade perennials such as carex, bleeding hearts, hostas, coral bells, jack in the pulpit, jacobs ladder, Helleborus or Lenten Rose and many other great shade plants.

4. When is the correct time to prune a burning bush?

A. Late fall after the leaves fall off would be best. It is always easier to see the branches and where problem areas are if you prune in the dormant season. Also, it will allow the plant to quickly seal up the wounds in the spring flush of growth. It is not advised to prune now because pruning woody plants after the beginning of August until when they are dormant can hurt the plant. This may cause the plant to push new growth that would be more sensitive to cool temperatures causing more dieback in the plant.

5. A caller wants to know how do you know when Butternut and Acorn squash are mature?

A. These are both winter squash varieties so the fingernail test will work just as it does with a pumpkin. When you think the winter squash is mature, push your fingernail into the rind of the fruits. If your fingernail pokes through the rind, the squash is not mature, if your fingernail does not puncture the rind, it is a mature fruit. Winter squash should have a hard rind.

6. This caller wants to know how to control windmill grass in his lawn?

A. For perennial grassy weeds such as windmill grass, there are two options for managment, either use a Glyphosate product, such as roundup, on the weed and then reseed or use a product containing Mesotrione product, such as Tenacity, on the weed and not harm the grass. The tenacity is more expensive but will not kill your grass so there will be no need to overseed.

This caller also wanted to know what would be digging up his grass?

A. This is likely due to either skunks or racoons digging the grass trying to get to grubs living in the soil. See the following NebGuides to learn how to manage these animals: Raccoons and Skunks Also, if this is due to grubs, apply a grub control next June to reduce the grub population in your lawn.

7. A caller has tomato hornworms in her garden. How can they be controlled? She also wanted to know what grubs come from and how to control them?

A. Sevin will work to control hornworms. However, the population is not usually terrible and the hornworms can be removed by hand and thrown into a bucket of soapy water for control. Grubs are the immature form of Japanese beetles, May/June Beetles, Masked Chaffer for the majority of species in Nebraska. They can be controlled in June with a grub control like the Merit products that contain Imidacloprid.

8. This caller has a 1.5 foot tall tri-colored beech that was planted in full sun this spring. About a month ago, the leaves turned brown. The caller is watering it 2-3 gallons of water every other day. What is wrong with the Beech tree?

A. Beech trees like to be in a more protected location, so this tree may be getting too much sun and too much heat. Because it is such a small tree, there is still time to replant the tree in a more protected and slightly shadier environment. Also, this small of a tree would not need this much water. When replanting it, keep it watered every other day with only about 1 gallon of water each time. After a few weeks in it’s permanent location, you can water with 1-2 gallons of water once a week and continue to back off on days between each watering as the tree grows larger. Remember, this small of a tree will not have a very large root system and it is as easy to overwater a tree as it is to underwater one.

9. How do you control moles in the lawn?

A. Moles are best controlled with a Harpoon trap that can be purchased at most hardware stores. For management tips, see this NebGuide on Moles

10. This caller has a hibiscus tree with a braided trunk that she thought would grow to zone 4, is this hibiscus going to be able to survive in Nebraska winters?

A. Unfortunately, it is highly unlikely that this is a hardy hibiscus that will survive winters in Nebraska. There is a hardy hibiscus that will survive our winters outdoors and those are suited up to zone 4, there is also a tropical hibiscus that is sold here as an indoor plant and will not survive our winter conditions outdoors. I would say that the tropical hibiscus would be the type purchased with a braided trunk. It can survive indoors during the winter months, so she can dig it up and put it into a pot to bring indoors for the winter.

2014-05-29 11.32.16

Clover in a lawn

This caller also wanted to know how to control clover?

A. Clover should be managed in the fall of the year. It will take multiple applications over multiple years to fully control clover in the lawn. Use 2,4-D or triclopyr products in the fall. It is best to apply these products around September 30th and again around the middle to the end of October.

The final question from this caller was if she should cut back her Virginia creeper plant that is turning brown?

A. Leave it alone and allow the plant to come out of the browning on its own. This is a common problem with Virginia creeper that is not terribly damaging to the plant.

11. How do you control anthracnose in tomato plants?

A. A copper fungicide can be used in a vegetable garden if necessary. However, often with home vegetable gardens it isn’t worth the time and money to spray our vegetable crops as the diseases usually only last for a short time and then fade when the temperatures change a little. However, it seems for this caller that the disease is a problem every year. For more information on controlling the disease and how to manage your vegetable gardens to avoid disease problems, visit this Nebguide on Leaf and Fruit Diseases of Tomatoes.

12. A caller has carpenter bees digging holes in her shed and wants to know how to control them?

A. Carpenter bees are a beneficial insect, except when they are burrowing into the wood framing of buildings reducing their structural integrity. They are best controlled with a dust formulation of sevin. Leave the dust in the holes a few days and then the holes can be filled in with a wood putty. For more information, see this guide from Lancaster County Extension on Carpenter Bees.

13. The final caller of the day wants to know how to control ragweed?

A. At this point, the plant is growing too strong to be killed with a herbicide. The best time to treat is in the spring before the plants have grown too large. At that time, they can be treated with 2,4-D. Now, the best control would be to dig or chop out the plants.

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Yard and Garden: July 7, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for July 7, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Bob Henrickson, Assistant Director of the Nebraska Statewide Arboretum

If you enjoy reading my Q&A from the show each week, take my quick survey at: http://go.unl.edu/44qr and be entered to win a free plant book or some free UNL gifts.

1.The first caller of the day has 10 lilacs growing in a lawn which are now getting a gray film on the leaves. What is causing this problem?

A. This is due to powdery mildew. This is a common problem on lilacs. Lilacs often get this disease if they are planted too closely together reducing air flow or if they are planted in heavy shade. If these plants are not growing in either of these environments, it is likely due to the wet spring we saw this year. Fortunately, this disease is not very damaging to the plants and there is no need to treat for it.

2. A caller has many American elm trees growing in his pasture that seem to suddenly be dying this year after the leaves turn brown and curl up on the branches.

A. Unfortunately, this is likely due to Dutch Elm Disease, which is still present and active in Nebraska. Many of our trees can grow for a few years and then the trees get large enough and conditions become conducive, that it shows up and kills the trees fairly quickly. The only management strategy is to remove and destroy the infected trees to reduce the spread to other trees.

chicory, Joseph M Ditomaso, Univ of CA-Davis, bugwood

Photo of Chicory from Joseph M DiTomaso, University of California-Davis, Bugwood.org

3. What are the blue flowers blooming along the roadside now and can the seed be purchased somewhere?

A. That is chicory, a non-native plant often used in roadside mixes. The seed can be found in some roadside mixes or at local seed sources.

4. A caller has a sunset maple with leaves that are curling and falling off the tree. What could be wrong with the tree?

A. This could be due to herbicide drift. Trees stressed by herbicide drift will often lose their leaves and push new growth. As long as they are producing new leaves that are not curled, the tree will likely be fine. However, many years of damage from herbicide drift can cause more stress and even possibly death.

5. This caller has voles in their yard. How can these be controlled?

A. Snap mouse traps can be placed in the runs perpendicular to the runs. These traps will catch and kill the mice. Here is a guide on vole control

6. A caller has a copper-colored beetle in her elm trees that are causing holes in the leaves. What would this be and how can they be controlled?

A. This could be a Japanese Beetle, an invasive insect from Japan. It is a green beetle with copper-colored wings. These beetles need to be controlled as they can do a lot of damage quickly. They chew on the leaves causing a skeletonization of the leaves as they leave behind the leaf veins. They can be treated with a insecticide containing imidacloprid.

7. A caller has a grass that grows in her lawn. The grass grows in a large circle about the size of a dinner plate and tends to turn brown in any kind of drought when the rest of the lawn does fine, but thrives in higher moisture content. What would this be and how can she make her lawn look more uniform?

A. This could be a cool season weedy grass species. They are often found in our lawns growing in a large circle. I would recommend spot spraying the areas of this different type of grass and then reseeding. This would be best done this fall. Be sure to spray the spot while it is still green and actively growing and use a product such as glyphosate. Overseed the areas in September.

8. This caller has hollyhocks with brown spots on the leaves. What could this be from?

A. This is likely due to hollyhock rust, a common fungus of hollyhocks. Remove the leaves as they develop the disease and destroy the leaves and plant parts removed in the fall cleanup. Fungicides can be used if necessary, such as a liquid copper fungicide.

9. A caller has peach trees that have developed some insects in the peaches making them unedible. What can be done about that?

A. There are a lot of different insects that feed on the fruits of peaches. The oriental fruit moth is one. For any fruit tree, either deal with some insect and disease damages throughout the years or keep your trees on a spray program. Spray every 10-14 days throughout the growing season with an Orchard fruit tree spray that contains two insecticides and a fungicide. Avoid spraying during full bloom. For more information, visit food.unl.edu/local-food-production

10. This caller has a sycamore that has shed some leaves and is now shedding bark. What is wrong with the tree?

A. The shedding bark could be normal. Sycamore trees have an exfoliating bark that is normal to give it the camouflage bark appearance. It may have been hit earlier this spring with anthracnose causing the leaves to drop. Anthracnose is a minor, but common, disease of sycamore trees. It is more prevalent in wet weather, such as this spring. There is no control for it, but the tree should be fine.

11. A caller has been trying to seed grass where a septic tank was and can’t get it to grow. What is wrong?

A. At this point in the year, it would be best to wait until fall to plant grass seed due to the heat, humidity, and lack of rain. However, if you have been trying in the spring and fall and can’t get it to grow, I would recommend getting a soil test done of the soil where this problem is occurring. This will help tell if the soil has other problems because of the septic tank or what was put back into the hole. It was also determined that this is an area around a large tree with a great deal of shade, if the area is too shady for grass, try a groundcover or a carex species that will grow better in more shade.

12. When is the best time to spray for bagworms?

A. Now would be a good time since the bags have emerged. Make sure you spray before the bags are 1 inch in length for best control. You can use any general insecticide for controlling bagworms such as sevin, eight, bifenthrin, tempo, or Bt can be used for a safer control method. Bt will not harm bees and other beneficial insects.

13. A caller has a Norway Spruce that is 8 feet tall. It has been drying up since this spring and looks like it is dying. The tree has been planted here for 5-6 years and is watering slowly every 2 weeks since the trees were planted. What is causing it to die?

A. This could be due to overwatering. The roots of the trees need to breathe in between waterings. If the caller is filling a moat around the trees with water every 2 weeks for this many years, it would be excessive.

14. The final caller of the day wondered if the yard could be sprayed to help with chiggers? He also wondered when the time was to use sedgehammer on the lawn?

A. Nothing can be sprayed on the lawn to entirely help with chiggers. The best defense against chiggers would be to use insect repellent that contains DEET and to wear light colored clothing. Sedgehammer is best used before June 21st or the longest day of the year to help reduce the populations of nutsedge for next year. However, it can still be used this late in the year to kill what is in the lawn this year.

Yard and Garden: June 23, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for June 23, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Hosts: Mike Onnen, Manager for the Little Blue NRD & Donnie Engelhardt, Assistant Manager for the Little Blue NRD

If you enjoy reading my Q&A from the show each week, take my quick survey at: http://go.unl.edu/44qr and be entered to win a free plant book or some free UNL gifts.

1.The first caller of the day wanted to know if it was time to spray for bagworms yet this year and what to use for bagworms?

A. Yes, the bags have emerged. There is time for a couple of weeks yet to get them sprayed, just make sure you spray before the bags are 1 inch in length for best control. You can use any general insecticide for controlling bagworms such as sevin, eight, bifenthrin, tempo, or Bt can be used for a safer control method. Bt will not harm bees and other beneficial insects.

Bagworm4

Bagworm

2. A caller has 2 large oak trees that when he parks his truck underneath it gets sticky from the aphids in the tree. What can be done to manage these?

A. The aphids are producing honeydew as an excretion and they do feed on the oak trees, but often this is not that damaging to the tree. You can spray for the aphids in the tree with a general insecticide, but if you give it a little time predatory insects will come in and kill the aphids. If you spray, you will kill the predators as well as the aphids. It is often not necessary to spray for aphids in a tree.

3. This caller has lilies that have grown too thick in her one garden bed. When can she divide these to transplant some in a new location?

A. This could be done this fall or you can wait and thin the lilies in the spring as well, either would be fine. I would advise against transplanting and dividing plants this time of year because in the heat, the plants don’t have enough roots to get to more water to keep them cool.

4. A caller has a weeping willow that has many leaves turning yellow and the tree is thinning. What would be wrong with the tree and how can it be managed?

A. This tree is likely dealing with environmental stress. There are not spots on the leaves to indicate a disease or damage that would be from insects. After viewing the photos, it is determined it could be due to improper planting as it looks too deep with no root flare. There may be stem girdling roots that would not be evident for a few years after planting.

5. How do you control ground squirrels in your yard?

A. There is a great publication on Ground Squirrels from the Internet Center for Wildlife Damage Management which shows how to set a trap for ground squirrels.

6. A caller has Iris, yucca, and prickly pear cactus that are all getting many weeds growing in and around these plants. The weeds include both grasses and broadleaf weeds. How can the weeds be controlled without injuring the desired plants?

A. The grasses can be sprayed with Grass-B-Gon or another similar grass herbicide. Unfortunately, there isn’t a selective herbicide that will kill broadleaf weeds and not kill broadleaf desired plants. For the broadleaf weeds, the best defense is to hoe the weeds out and mulch the garden in the future to hold the weeds back.

7. This caller has a plum hedge that has holes in most of the leaves throughout the hedge. The holes form initially as a brown spot and then a hole appears. What would cause this?

A. This is likely due to herbicide drift. There is no control for that, but if it is minimal it shouldn’t impact the hedge too much. However, multiple years of herbicide drift to the same plants can start to stress and in some cases kill the plants.

8. A caller has onions that have formed a soft, brown spot on the onions when they were dug recently. What would cause this?

A. This is likely a rot issue that developed from a pathogen in the soil. It is always best practice to rotate the crops. Also, ensure that you properly cure your onions before storage.

9. How can you control sandburs?

A. Crabgrass control in the spring will work for sandburs as well as foxtail and crabgrass. All of these are annual grasses.

10. A caller has tried to plant roses in the same location for a couple of years now and it seems like they grow to about 18 inches, bloom, but then die over the winter months. The are planted in a garden with rock mulch, watered with a bucket of water as needed, and were pruned off in March. Why can’t the caller get the roses to live longer than one year?

A. This sounds like mostly environmental stress to these plants. Rock mulches are hot and absorb no water, switch to a wood chip mulch to cool the roots and hold moisture. Watering should be done with a soaker hose or other type of sprinkler system. When a bucket of water is poured over the plants as needed, the water fills up the top pores of the soil surface quickly and then spread out rather than down. A slow trickle on the plants for a while each week to wet the soil down to about 6-8 inches will be more beneficial. Pruning of roses is best done in the middle of April once growth has begun further to ensure healthy wood is not also removed with the dead wood too early in the spring. Add extra mulch around the plants in the winter months, up to 4-6 inches deep in the winter months, then spread the mulch out to 2-3 inches deep during the growing season. Extra mulch in the winter will help protect the plants from inconsistent temperatures in the winter.

11. This caller wants to know when to dig up garlic? He also wants to know if bleeding hearts can be cut back now?

A. Garlic should be harvested in July after 30-50% of the leaves have died back. Harvest during dry weather and leave the bulbs on the ground to dry for a week before storing. The flower stalks of bleeding hearts can be removed, but the leaves need to be left on the plants to build sugars for next years growth and flower production.

12. How can grasshoppers be controlled if they are in the flower garden?

A. Any general insecticide will work for grasshoppers in flower gardens. Sevin, eight, tempo, bifenthrin, and others will work for flowers. When treating grasshoppers, it is also important to treat the grassy areas of roadsides and ditches where grasshoppers are often found.

13. This caller has grass growing in his asparagus patch. How can the grass be controlled?

A. Hand pull and apply a mulch to the asparagus patch. The earlier you get the mulch applied in the season, the better the control will be. Also, after harvesting is complete, the asparagus can be snapped off below ground level and Roundup or another glyphosate product can be applied as long as there is no green asparagus above the ground.

 

Grasshoppers, J. Larson

The four main pest species of grasshopper in Neb. Top row two striped grasshopper adult, red legged grasshopper adult. Bottom row differential grasshopper adult, migratory grasshopper adult.

14. How can you control grasshoppers in the vegetable garden?

A. Sevin, eight, and bifenthrin are labeled for use in the vegetable garden. Also, remember to treat for grasshoppers in tall grasses along roadsides and ditches. Follow the PHI (pre-haravest interval) to know how many days after application necessary to wait to harvest the vegetables.

15. A caller wants to know when to transplant peach trees?

A. Fall or spring are both good times to transplant any trees.

16. The final caller of the day has a pond with moss or duckweed in it making it cloudy. What can be done to clean up the water?

A. Avast SRP is labeled for Duckweed and Copper sulfate can be used for Algae.

Yard and Garden: June 2, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for June 2, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Graham Herbst, Community Forester from the Nebraska Forest Service

If you enjoy reading my Q&A from the show each week, take my quick survey at: http://go.unl.edu/44qr and be entered to win a free plant book or some free UNL gifts.

1. The first caller of the day has a Hen and Chicks plant that has grass growing in it. What can be done to remove the grass? She also has spiders in her lawn, what can she do to control them?

A. Grass-B-Gon is a product that contains the active ingredient Fluazifop. This is a grass herbicide. This product or any others containing Fluazifop can be sprayed directly over broadleaf plants with no damage to the desired plant. The spiders are not an issue outside in the lawn, in fact, they are beneficial. Spiders in the lawn are feeding on insects, many of which cause problems to our plants or bother us. Outside, spiders are beneficial. To keep them from coming indoors, home barrier sprays or tempo can be used around the foundation of the house to keep spiders and insects outside. If there is a fear of spiders, the tempo could be used where the spiders are seen.

2. A caller has a mock orange that has not bloomed for the past few years and now this year it finally is blooming some. Should it be removed? Why hasn’t it been blooming?

A. This could be due to a maturity issue. Many of our woody plants need to become established and get to a certain age before they will begin blooming. It could also be due to pruning time. Mock Orange bushes need to be pruned right after they finish blooming because they bloom on last years growth, or old wood. If they are pruned in the fall or early spring, the blooms would be cut off.

3. When is the proper time to spray for bagworms on blue spruce trees?

A.Spray when the bags are small to get the best control. It is best to spray after the bags emerge in the late spring to early summer but before the bags get longer than 1 inch in length. Mark a branch with a bag on it now and keep checking it to determine when the bags have emerged.

4. A caller has 6 table grape plants that had grapes set on. Now the grapes are dropping off and 70% are gone from the plants. What has caused these plants to loose all of the grapes?

A. This could be due to frost damage. Here is a guide from Oregon State University to describe the many factors that can hinder fruit development in grapes.

Forsythia-Richard Elzey, Flickr

Forsythia, Flickr image courtesy of Richard Elzey per CC license

5. Is it too late to prune forsythia this year?

A. It is too late to prune and not cut off any blooms for next year. Spring blooming shrubs should be pruned shortly after they finish blooming for the year. Forsythias bloomed in March this year, so it would already be starting the formation of flower blooms for next year, pruning them now would cut those buds off. If the intent is to just prune a few branches just a little, it wouldn’t impact the overall blooming of the shrub, but pruning too heavily will lead to little or no development of flowers.

6. A caller wondered where they could go to find the wrap around water bags for trees?

A. Local nurseries should carry them or there are many online locations where you can order them. These bags are beneficial to help keep the root ball moist to help get new trees established.

7. Can Grass-B-Gon be used in strawberries or phlox and will preen reduce the number of runners grown off of strawberry plants?

A. Grass-B-Gon is not labeled for use in fruit bearing tree crops and vines. So, it cannot be used in strawberry plants. It would be good to use for grasses growing in phlox and not cause any harm to the phlox. Preen stops the germination of seed to reduce weeds grown from seed in the garden, so it will not harm runners which are growing off an existing plant, not from seed. Check to make sure the preen you are using is labeled for use in strawberries, the general preen is not for use in vegetable gardens.

8. How do you transplant a wild rose?

A. First, make sure it is on your property. Then, just make sure you dig up as much of the rootball as possible and replant it right away. You could also try taking a cutting from one of the branches and dipping it into rooting hormone and placing it into a pot of gravel to get roots to grow. Once roots develop, you can plant the rose.

9. A caller wants to build a privacy border with shrubs. Would Burning bush work for this or are there other options to choose from?

A. Burning bush would be a great privacy wall with good fall color. Other shrub choices would include serviceberry or any of the viburnums. You could plant it now, just make sure the plants get plenty of water with it being this hot and the roots being minimized due to transplanting.

10. This caller has tomato plants that when they planted it they saw grubs and wireworms in the soil around it. Should they treat for this and if so, what should be used?

A. Grubs are not controlled effectively around vegetable gardens because the chemicals with the best control are not labeled for use in the vegetable garden. However, there is a fairly high threshold of grubs and wireworms in the garden before damage is too high. A few grubs or wireworms throughout an entire garden will not cause any real damage. The plants they are most problematic on would be the root crops such as potatoes.

11. This caller had 2 questions: Her asparagus has been planted in this location for 30 years and is quite spindly, why is that? Her peonies are done blooming now, can she deadhead the spent flowers?

A. The asparagus is regularly fertilized so the small spears could be due to heavy harvest or it could be getting old or too crowded. It would be time this year to stop harvesting to allow the plants to recover and make sure to stop sooner next year. Once peonies and iris plants have completed their blooming period, the flowers can be cut off and composted. Leave the leaf material on the plant to build sugars to help with the flowering next spring.

12. How do you control weeds in asparagus?

A. Hand pulling and mulch would be the best options for weed control. When the plant is done in the fall and the leafy material is all removed below the ground level, the existing weeds can be sprayed with Roundup as long as no green material from the asparagus is above ground or showing. Here is a good explanation from Backyard Farmer of why we don’t use salt on asparagus for weeds and how to effectively control weeds with Roundup.

Carpenter Bee, J. Kalisch

Carpenter Bee photo from Jim Kalisch, UNL Entomology

13. A caller has carpenter bees digging holes into the roof of a patio. What can be done about this?

A. You can plug those holes with caulk or putty or use a sevin dust in the holes. For more information on Carpenter Bees, see this article from Retired Extension Educator, Barb Ogg

14. This caller has puncture vine in the lawn. What can be used to control it?

A. 2,4-D is a good way to control it in the the spring before it blooms.

15. A caller has peonies that need to be transplanted. Can they also be divided when they are transplanted?

A. Yes, they can be cut into a few pieces when they are transplanted this fall. Just make sure that each section you cut off the plant has 3-5 eyes which are more like pink noses or knobs on the roots of the plant. Peonies are best transplanted and divided in September or October.

Yard and Garden: May 19, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for May 19, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Jim Kalisch, Insect Diagnostician for Nebraska Extension

If you enjoy reading my Q&A from the show each week, take my quick survey at: http://go.unl.edu/44qr and be entered to win a free plant book or some free UNL gifts.

1. The first question of the day was from a gentleman wondering how to tell when to water his self-watering containers? There is no viewer or gauge to show the water level on the outside of the container.

A. Because a self-watering container is continually watering the plants in it, it can always be refilled. In this case, this container will keep your plants watered for at least a week to two so, they should be refilled before they completely dry up. I would suggest refilling the reservoir every week to 10 days.

Bagworm4

Bagworm

2. A caller has bagworms in their cedars. What is the best way to see them before they get too big to treat?

A. They haven’t hatched yet this year. Mark the branch you have a living bag on with flag tape to check the same bag every week from now until they hatch. You can also place a few bags in a container and keep it in the tree to see when they hatch in the container. Wait a couple of weeks after the initial emergence to ensure that all of the bagworms have hatched before spraying. The bags in the shade will take longer before they hatch. Once they have hatched, Bt is a good insecticide to use when they are young or you can use a product containing bifenthrin in it for longer lasting control.

3. This caller is wondering what types of problems we can expect in the garden, lawn, and trees this year due to the excess rain?

A. The rains in the spring tend to lead to more fungal diseases this time of the year, but they are not terribly harmful and many should fade out as the summer heats and dries up. Many things to watch out for would include fungal diseases in the lawns and trees. We are already seeing Peach Leaf Curl, different fungi in blue spruces, anthracnose on the leaves, and mushrooms popping up in our lawns. We will also see more problems from earthworms and fungus gnats which are mostly nuisance problems.

2015-09-22 18.45.39

Squash bugs on a zucchini

4. How do you effectively control squash bugs in the vegetable garden?

A. Squash bugs are difficult to control in our cucurbit vegetables including zucchini, squash, pumpkins, gourds, melons, and cucumbers. The best option is to kill the adults when they first emerge to manage the population before it explodes. Watch for the eggs as they develop on the underside of the leaves to destroy them before they emerge. Switch to other chemicals for management besides just using “Sevin” for control, which they are becoming resistant to. There are also lures that can be used for them which might help early in the season.

5. A caller has an Oregon Trail Maple that leafed out early this spring. Now the leaves are slightly cupped and turning yellow along the edges. What would be causing this?

A. This sounds like frost damage. If the leaves came out early, they may have been nipped by a light frost in late April. We are seeing this problem throughout many trees and shrubs this spring. The leaves may drop entirely from the tree, but the tree will then push secondary buds to produce new leaves that are not injured.

6. This caller wants to know how to propagate a lilac and a hydrangea.

A. For lilacs: A cutting can be taken from the shrub. Cut off a small, pencil-sized, branch and place it into rooting hormone than plant it into a pot of gravel that is kept moist. Once roots have formed, the plant can be transplanted into the ground. They can also be propagated through a process called layering which is where you bend a flexible branch down to the ground and plant it to allow roots to form on the branch while it is still attached to the main plant. Once roots form, cut it from the parent plant and transplant it. There is more information on this in the NebGuide: Lilacs

Hydrangeas can also be layered to produce new plants or they can be divided. It is too late to do the division this year, but early next spring you can dig up the plant and use a spade to divide the main plant and replant the pieces. Depending on the side you can get 2-4 pieces from a divided plant.

7. Is cedar-apple rust damaging to cedar trees?

A. Cedar-apple rust shows up in the spring on cedar trees as a orange, slimy, ball with horns. This is the gall that opens up with rains in the spring. Cedar-apple rust is not harmful to the cedar tree, it just uses the cedar trees as an alternate host through the winter. When these galls are seen on the cedar, that is the time to spray any susceptible apple, crabapple, pear, or hawthorne tree to avoid damage to them. For more information view this NebGuide

8. This caller has a pink peony that hasn’t bloomed well this year. There is some discoloration and fuzzy appearance to the leaves and buds. What would cause that?

A. This sounds like botrytis blight, a common fungal disease to our peonies. It is not very harmful to the plant itself, so it is not necessary to control it. In the fall, make sure you remove and destroy all of the plant material to reduce the spread to your plants next spring.

9. A caller has a Chanticleer Pear with leaves that have black spots on them and the top isn’t leafing out this spring. What would cause that?

A. This could be due to frost damage as well. Or check the tree for oozing sap along the trunk or branches. The damage could be from borers. It might also be from fireblight which would cause the leaves to turn black on some branches where the end of the branch hooks over like a shepherds crook. Fireblight is likely since this showed up in the tree last summer. If it is fireblight, prune out the infected branches and dip your pruners into a bleach water solution in between the cuts.

10. This caller has roses that had dieback from the winter. She pruned them off in early April and now it looks like the only live growth is coming from the ground. What is wrong with her roses and will they come out of it?

A. Unfortunately, these roses seem to have more dieback from the late frost we saw in April. If there is no green growth showing up on the main part of the plant, it is likely that it has died back. The roots would be shooting the new growth from the ground, but that is not going to be the same type of rose that you had there before because our roses are often grafted. The growth from the ground would be from the rootstock so it wouldn’t be the size and color of rose that was originally purchased. Unfortunately there is nothing that can be done about that. It might be time to go and choose some new rose colors for your garden.

11. A caller has a river birch tree that dropped its leaves in the summer last year. The leaves now are yellow and only the top half of the tree has leafed out this spring. They are 20 year old river birch trees. What would be causing this problem?

A. Look on the branches of the tree for signs of bronze birch borer. Some of the signs of this borer would be rippling on the branches or holes in the stem or branches. If you find the signs of bronze birch borer, you can treat it now with a borer spray or with a systemic insecticide.

12. A caller has a river birch tree that was growing in a clump and one of the trunks of the group died out. Should it be removed now?

A. Yes, any dead part of a tree should be removed as soon as it is noticed. A large part of a river birch, like this, could be hazardous if left standing after it dies. Unfortunately, when that branch is pruned off decay will likely begin but there is no way to prevent that at this point. This will likely be a large portion of the tree removed and that large of a pruning cut may not ever heal over entirely. When a branch doesn’t seal up, decay can get into the tree causing more damage. We don’t advise painting the stump with anything.

13. A question came in via email regarding a red twig dogwood. This dogwood is 4-5 years old and has never been pruned. Following the storms this week, some branches are falling over blocking a mowing path. Can those be pruned now? What should be done with it in the future?

A. Broken branches can be removed at any time. If these are just bending over, they could still be removed if necessary, but they may pop back up to their normal standing position. For future, red twig dogwoods should be pruned to the ground every 3-5 years to maintain that good red color on the twigs. They should be pruned in the late winter to early spring.

14. A lady called who has a Cranberry Bush Viburnum that has dead branches in it. Can those dead branches be pruned out now?

A. Yes, dead branches should always be removed when they are noticed. Check to ensure that these branches didn’t die due to Viburnum borers, if so, treat with a borer spray or systemic insecticide.

15. The last caller of the day has 2 different plants that have problems. A maple tree has brown specks on the leaves and they are falling off the tree. A Peony bush has leaves that are turning yellow along the edges of the leaf. What would be causing these two problems?

A. These both sound like frost damage. They will both be fine. The maple may drop all the damaged leaves and put on new growth.

Yard and Garden: April 7, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for April 7, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Hosts: Jonathan Larson, Extension Entomologist from Douglas-Sarpy Counties & Jody Green, Extension Entomologist from Lancaster County

1. The first question was to see if we could guess the caller’s favorite insect that was described as a moth with large, light green wings and feathery antennae?

A. This is a luna moth

2. A caller has moles in the yard and wants to know how to manage them?

A. A harpoon type of trap can be used, but should be prepped ahead of installation. This trap tends to work best if you stomp on a run to determine if it is an active run.  If it gets pushed back up, it is an active run. Stomp on this area a couple of more times and then set the trap to ensure the mole moves through the area. For more information on moles, click here for a publication from UNL on moles.

3. This caller wants to know how to get rid of creeping charlie in a lawn?

A. Triclopyr or a 2,4-D product can be used in the fall. For best control, use the product twice in the fall 2-3 weeks apart. September 30th and October 15th would be good dates for application. This is a tough weed to control, so it will take multiple years of multiple applications. A spring application of either of these products can be used as well to knock the weeds back for this year.

4. When can you transplant daylilies? Can they be planted into an area on the east side of the house with rock mulch?

A. Wait a couple of weeks until mid-late April to transplant them when the temperatures have warmed up more. Also, as long as the area is receiving at least 6 hours of sunlight daylilies will grow fine. This is a tough plant that will grow well in most conditions.

5. A caller has strawberries that had botrytis last year. When should they be sprayed to prevent the disease this year?

A. Apply from 5-10% bloom until flowers have finished blooming. For more information see the Midwest Small Fruit and Grape Spray Guide from Midwest Universities including UNL.

6. This caller has a pear tree that last year had orange spots on the leaves later in the season. What is this and how can it be controlled?

A. This is due to a rust disease, Cedar-Hawthorn Rust. It is more common in years following a wet spring. The timing for management is in the spring, May and June. See this NebGuide on Cedar-apple rust and related rusts of apples and ornamentals.

7. A caller has started corn, watermelons, and cantaloupe indoors from seed. The seedlings are getting quite large. Can they be transplanted outdoors now?

A. Unfortunately it is still too cold to plant these crops outdoors. These are warm season crops that should not be planted until early May after the frost-free date. These crops could be direct seeded at that time or transplanted but they tend to not do well as a transplant.

8. A caller has 2-year-old rhubarb plants that have come up and have thin, limp stalks. What is wrong with the rhubarb?

A. This could be due to crown rot. Rhubarb is very sensitive to high moisture soils and will often develop a crown rot in these situations. Those plants that have limp stalks should be removed and you can replant in a new location where it has more well-drained soil.

Bagworm4

Bagworm

9. When and what should you spray for bagworms?

A. May-June is the time frame for treating bagworms. It is best to spray them when the new bags are 1/2-1 inches long. Longer than that and they won’t catch as much of the pesticide to die as well. For spray choices, any general insecticide will work, but using Bt would be the least damaging to other insects because Bt only affects insects in the Order of Lepidoptera which includes butterflies, moths, and skippers.

10. A caller has Asparagus that has a green moss-like structure growing on top of the ground around it. What is it and what can they do for it?

A. A picture would be helpful in identifying this pest. If it is actually a moss, they may look into the water in the area because it is likely that it is too wet. If it is a weed, pull or hoe the weed and then add a layer of mulch to prevent further weeds from coming in.

11. This caller wanted to know what to do to grow bigger onions and if they should put Epsom salt on their tomatoes to help them grow more?

A. These onions are growing 3 inches apart, they should be spaced out more for larger sized onions. Place plants or sets 1-6″ apart in the rows, and 12-24″ between rows. For bulb production, plant onions in early spring. The number of leaves that form prior to bulbing determine the ultimate onion size. Since bulbing in each cultivar is triggered by a specific daylength, early planting is the most effective method of increasing bulb size, by allowing more time for leaves to form. If the onions do not grow well before bulb induction, the final bulb size may be smaller than desired. Avoid sets more than ¾ inch in diameter because they are likely to produce seed stalks.

As for the Epsom salt on tomatoes, no you should not apply this to your soil when you plant tomatoes. Our soils have a sufficient amount of magnesium and sulfate, which are the 2 ingredients in Epsom salt, so there is no need to apply more. If you need fertilizer, use a general fertilizer from the nursery or garden center.

12. A caller has a Japanese maple that was injured last May when the leaves curled up and fell off. The leaves never regrew through the summer last year. Will it come out of it?

 A: If it happened that early in the year last year and didn’t put on new leaves, it may be dead. Give it time this spring to green up. You can check if the tree is still alive by scraping the bark on a branch, if there is green underneath it is still alive, if there is brown it is dead.

13. What can you do to manage windmill grass?

A: Windmill grass is a perennial weed. You can use roundup and overseed or use a product containing mesotrione or Tenacity that will not harm your turf. Use the Tenacity in the late spring.

14. This caller wanted to know what to use for a pre-emergent herbicide in a strawberry patch?

A: Preen that is labeled for use in a vegetable garden would be allowed in a strawberry patch. The best control for weeds in strawberries would be to use mulch.

15. Can you use plants to repel insects?

A: Some plants may deter a few insects for a short time, but no, the plants are not concentrated enough to work against the insect pests.

16. A caller has an arborvitae that turned brown on the North side last fall. Will it be ok?

A: This could be due to bagworms or due to environmental stress. Arborvitae trees don’t like the sudden cool down in the fall and it can cause part or all of the plant to die quickly. Unfortunately, if the tree has turned brown all the way back into the trunk, the tree will not regrow on that section. Removal and replacement may be a better option for this plant.

17. This caller wanted to know when they can reseed their lawn and with what?

A: Mid to late April is the best time to reseed a lawn in Southeast Nebraska. Reseed with 100% Turf-type tall fescue or 100% Kentucky bluegrass or a 50% mix of each.

Squash bug-NH-pic monkey

18. A caller asked what to do about squash bugs in their vegetable garden?

A: Fall sanitation and cleaning up the garden will help a lot to reduce the eggs in the soil around your garden. When they do start coming out in the summer, you can use sevin, eight, or bifenthrin to control them. You will have to spray every 10-14 days through the growing season. Watch the Pre-Harvest Interval to know when you can harvest after spraying a chemical on your plants. You can also smash or remove the eggs you see which are tiny, football-shaped bronze colored eggs on the underside of the leaves typically found in the crotch of the leaf veins.

Yard and Garden: August 5, 2016

Yard & Garden for blog

This is the Q&A for the Yard and Garden show for August 5, 2016. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 5, 2016. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Graham Herbst, Community Forester Specialist with the Nebraska Forest Service

If you enjoy reading my Q&A from the show each week, take my quick survey at: http://go.unl.edu/9b24 and be entered to win a free plant book or some free UNL gifts.

1. The first question of the day was a walk-in client wondering what the weird structures in his yard were?

A. These would be fungal formations. The one that popped open is a puffball and the other is a type of mushroom. Neither of these are edible, they are both poisonous. They will develop in a yard from decaying roots of old or removed trees. They can be removed manually if you would like or they will go away on their own.

2016-08-05 10.14.05

Puffball on the left, Mushroom on the right

2. A caller has a small tree that is leaning that looks like a palm tree, what is it and why is it leaning?

A. After visiting the home after the show, it was determined that the tree was a sumac. It is leaning because that is the growth habit of a sumac. They tend to form a colony and lean every direction for sunlight.

3. A caller has a zucchini plant that just all of a sudden started dying off. Is this plant just done for the year or can something else be wrong with it?

A. This is probably due to squash vine borer. There is no way to fix the problem once it has gotten to the point of wilt and death. When you remove the plant, cut open the stalk to see the borer caterpillar. For the remaining plants use sevin, eight, or bifenthrin at the base of the plants to reduce the chances of those plants getting the borer as well. You can also wrap the base of the plant with aluminum foil or a toilet paper tube to protect it from borers laying eggs to bore into the plants.

4. A caller has cedar trees that have pine cone structures all over them that are killing the trees. What are these and how can they be controlled?

A. Those would be bagworms. At this time of the year it is too late to control them as their feeding has greatly reduced and possibly stopped for the year. Once they are in their bag the sprays cannot penetrate the bags to get to them so there is no need to spray now. Pick off and destroy all the bags you can get to and next spring watch for them sooner to spray at the correct time of the year.

Bagworm4

Bagworm

5. With bagworms, will sevin work for spraying them?

A. Yes. Sevin, eight, bifenthrin, tempo, malathion, or bT are all good insecticides to use when the bagworms are actively feeding.

6. A caller has wild cucumber growing on trees. How can this be controlled?

A. This weed has shallow roots and will pull out easily. You can treat with a herbicide, but not as a spray because that would harm or even kill the tree it is growing on. You can paint roundup on the leaves to help control it.

7. This caller has a mature maple tree that has mushrooms growing in the center of it. Can it survive?

A. It is best to manage the trees shape throughout the life of the tree to help it from having to have large branches removed. At this point there is no way to fix the hole and decay that have already begun. If the tree is in a location that it will not hit structures or people it can be left up longer, but it would be best to have a certified arborist come take a look at it to determine if the tree is safe to stand or needs to be removed.

8. A caller has a tree that the roots were exposed during work on the house nearby and then the roots were covered back up. Now, there are a lot of tree suckers coming up throughout the lawn. Can Tordon be used to control these?

A. Tordon is not labeled for use in a landscape setting. Also, using any type of insecticide on the suckers could harm or even kill the main tree. Since these suckers are all growing in the lawn, it would be best to just continually mow them off. The suckers appeared because the tree was stressed from the construction around the roots. Sucker stop can be used to slow the growth of the suckers but not completely eliminate them.

9. An email question was asked how to control locusts that are taking over a pasture?

A. Grazon is a good choice for pastures as a full foliage treatment during June. You can cut the stump and do a basal treatment anytime. Another choice would include Dicamba or a Trimec product that contains dicamba.

10. Another email question came in with a cottonwood tree that has brown tips on the leaves and lots of ants on the tree. Are the ants causing the problem? Can this be controlled?

A. The brown tips could be from sunscald which is due to the heat and drought we have faced lately. Aphids are probably also present on the tree which would bring the ants in to feed on their honeydew excretions. The ants are not harmful to the tree. The aphids are not causing much of a problem. Control measures are not necessary. Mulch the tree and water it to help with sunscald.

11. A caller from Iowa has hostas that were variegated in the leaves for the past 20+ years and now the leaves are solid green. What is causing this?

A. This is called reversion. The plant is a hybrid or cultivar that has reverted back to the original plant or parent plant with solid green leaves. It will not turn back into the variegated form.

12. A caller wanted to know why windbreaks and trees along creeks are being removed?

A. Sometimes the trees get old and start to become a hazard after they die. It also allows for more farming areas. These windbreaks are beneficial to wildlife, insects, and soil microbes and to help reduce water pollution from pesticide and fertilizer runoff.

13. The last caller of the 2016 season wanted to know when to transplant clematis, iris, peony, spirea, and general perennials?

A. all of these can be transplanted in the fall. Wait until mid to late September before doing this to get through the hot, dry weather. Could be done in the spring with some of these as well, but fall would be great.

Thanks for all of the great questions on the show and for reading the blog posts! I look forward to another great season of Yard and Garden Live in 2017!! Keep reading my blog for other great updates on keeping your yards and gardens “Green and Growing”!

Yard and Garden: July 1, 2016

Yard & Garden for blog

This is the Q&A for the Yard and Garden show for July 1, 2016. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 5, 2016. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Bob Henrickson, Assistant Director of the Nebraska Statewide Arboretum

1. The first caller of the day wants to use weed fabric and white rocks around the foundation of his house. Is this a good idea?

A. This can be done, but as horticulturists, Bob and I are always for more greenspace and less rocks. The weed fabric will work for a short time but often weeds will germinate through or on top of the fabric and it is hard to remove or change after the fabric is in. A good option would be to plant shrubs and perennials in there to help hide the foundation to the siding. Wood chip mulches will help with weed control around the plants.

2. A caller has a problem with ground squirrels in their lawn.

A. a trap can be built to control ground squirrels. The Internet Center for Wildlife Damage Management has a good guide for 13-lined ground squirrels.

3. A caller has bees in their sand play area. What can be done about it?

A. The best control for this would be to cover the sandbox so the bees cannot burrow into the sand to build their nest. If this can’t be done, you can sprinkle a little sevin in the holes where the bees go to nest. This is not the best option if you have kids playing in the sand because the chemical would not be safe for that. Otherwise, spraying the sandbox with water or soapy water will deter and possibly kill the bees.

4. This caller has a bald cypress tree that had lacebugs last spring. This year it hasn’t leafed out on the branches, most of the leaves are on the trunk. What can be done for this tree?

A. Removal and replacement. When a tree only leafs out on the trunk there is some reason that the flow of water and nutrients is not going through the whole tree. This could be due to borers or some type of root issue. Even with trees that are 8 years old, they could have had a root injury or been planted too deeply or had a stem girdling root that is now causing death of the tree. There is no cure for this at this point in the trees life.

5. A caller has a new lawn that they are trying to rejuvenate. What would the process be?

A. They are watering 2 times a week with a sprinkler for a couple of hours at a time, this should be sufficient. Stick with what you have been doing and don’t abruptly reduce it. Fertilize with the holidays: Arbor Day, Memorial Day, Labor Day, Halloween. So at this point don’t fertilize until the fall. Fertilizing in hot weather can cause more stress or leaf burn. For weed control, use crabgrass pre-emergent in the spring with the Arbor Day fertilization and use 2,4-D in the fall.

6. What to do when planting a tree that is badly rootbound?

A. It is hard to fix a tree when the roots are already rootbound. Once they begin to grow in a circular pattern, they will continue to do that for life, and damage doesn’t always show up until the tree is 10-15 years old. It is best to look at the roots before purchasing to choose a smaller tree with healthy roots. Also, when you get it home, remove the excess topsoil from the top of the rootball to ensure that it gets planted at the correct depth.

7. An email question came in to ask what to do for stump removal where they cut down and removed some shrubs?

A. Keep cutting the suckers off as they regrow and mulch the area if you just want to be rid of the plants. If you want to replant into the area, you will have to remove the stumps by digging them out or using a stump grinder to grind them out. Do not use Tordon in this area as it is against label regulations and it will not speed up the process and it can kill other desirable plants.

8. A caller has a firethorn plant with spidermites that they see on the plant every year and it causes them to loose many leaves each year. What can be done for them?

A. A strong stream of water will often work for spidermites. If the population is too high you will have to use insecticidal soaps. If this is an annual occurrence you may want to remove these shrubs and replace them with something that isn’t so problematic in this area.

9. What do you do for sandburs?

A. Sandburs are an annual grass, so crabgrass pre-emergent herbicides in the spring will help reduce the population by stopping germination. At this point in the year you can use a post-emergent grass herbicide such as Drive. Keep the area mowed to reduce the seed production for next year.

10. A caller has honeysuckle that is now invasive through his yard. What can be done to eliminate the honeysuckle plants? Also, is hickory a good tree for Nebraska? Why don’t we see hickory trees planted more?

A. Continual cutting of the honeysuckle will eventually kill it. You may want to try to dig up the plant to help reduce the problem. You can also treat the stump with roundup and/or 2,4-D. Use 2,4-D products in the spring or fall, it is now too hot to use this product without possible damage to desirable plants. Hickory is a great tree for Nebraska, it is just underutilized. Good hickory tree choices for Nebraska include Shagbark Hickory, Bitternut, and King Nut. Shagbark Hickory was the Great Plants of the Great Plains Tree of the Year Selection in 2011.

 

Japanese Beetle, 7-16 Acreage

Japanese Beetle adult on the left and immature on the right. Photos by Jim Kalisch, UNL Entomology.

11. A walk-in listener brought in a green beetle to be identified.

A. This is a Japanese Beetle. It is identified by the green metallic color, gold elytra, and white spots along the sides of the abdomen. This is an invasive insect from Japan that feeds on over 300 species of trees and shrubs, it favors roses and plants in the rose family. It will cause a skeletonization of the leaves as the adult feeds. As immatures they are a white grub that feeds on the roots of our turf. Management of white grubs in the turf will reduce the population. As adults, they can be controlled with general insecticides such as sevin, eight, bifenthrin, malation, or others. Don’t use insecticides on the flowers or flower buds to help with pollinator populations.

12. The final question of the day was from an email asking what chemicals do you use for bagworms?

A. Bagworms can be controlled with Bt, spinosad, sevin, eight, malathion, or tempo. The treatments need to be completed before the bags are smaller than 1/2 inch in length. You can also remove bags as they are seen and throw them into a bucket of soapy water to kill them without pesticides if you can reach them all.

Yard and Garden: May 20, 2016

Yard & Garden for blog

This is the Q&A for the Yard and Garden show for May 20, 2016. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 5, 2016. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Natalia Bjorklund, Dodge County Extension Educator

1. The first caller of the day has a problem getting grass to grow where he removed an asparagus patch. What can he do to get his grass to grow?

A. This is a situation where it could be a few things attributing to the problem. He was keeping the seedbed watered, by watering it 3 times a day for about 10 minutes each time he watered. Watering is important for seedlings, they need to be kept moist, so short, frequent waterings are necessary. This area could be compacted from years of asparagus growth, so it might be beneficial to till the area up prior to planting. The other issue he is facing this year is that it has been quite cool this spring. Mixing the cool temperatures with the moisture, it might be too cold for germination. It is suggested to try again with new seed after tilling the soil up and a soil test may be necessary after that to ensure the soil is ok after so many years with asparagus on it.

2. A caller has a newly planted red maple tree with holes in the leaves. They do have black spots on the leaves as well. The new growth seems to not be affected like the original leaves. What would be the problem? Is this an insect issue?

A. This could be a leaf spot fungus with black spots on the leaves that have died out. When a leaf spot occurs on tree leaves, often the dead area will fall out of the leaf. Leaf spots are not very damaging to our plants. Since the new growth seems ok, it shouldn’t be treated and the tree will grow out of it and be fine.

3. A gentleman has evergreen trees that have brown tips on the branches. Is this being seen in other locations?

A. This is probably just an environmental problem on the branches that should fade in time. It is being seen in other trees, especially in white pines which are facing problems with winterkill, a common issue where the tips of needles on white pines turn brown after strong winter winds. It is not a concerning issue.

4. This caller wants to know how to control weeds growing around her containers that she is growing tomatoes and strawberries in? Can any chemicals be used that close to these crops?

A. Tomato plants are especially sensitive to chemical drift especially from 2,4-D which is a common herbicide used for lawn weeds. To be safest and not have problems from the 2,4-D being that close to the tomatoes and strawberries, mechanical control would be the safest option. mulching around the containers will help to keep the weeds from coming back.

5. A caller has blackberry leaves that are turning orange and then back to green. What would be causing this?

A. This sounds like the plant is having an issue with rust. The rust covered leaves then are falling off and new, uninfected leaves, are reappearing. Remove all infected leaves as soon as you notice the fungal spores. Rust will not kill the plant, it may show up on the berries slightly. Chemical controls are not necessary for a home gardener.

6. A gentleman planted fescue grass seed this spring and it seems to be a thin stand. Should it be overseeded? Will it fill in?

A. Fescue does not tiller out like bluegrass does. So it should be overseeded to help fill in the gaps in the turf.

7. What chemical can you use for tree stumps to help keep them from growing back?

A. 2,4-D is a good option to apply to a newly cut stump or drill into the stump and pour it into the holes. It can be mixed with Roundup to help as well. Do not use Tordon in a landscape setting as this would be a direct violation of the law.

8. This caller transplanted peonies a few years ago and they haven’t bloomed since they were moved. What is wrong with them?

A. If peonies are planted or transplanted too deeply in the soil they will not bloom. Dig the plants up and reposition them higher in the soil profile. It can be done now or in the fall, the fall would be the preferred time of the year.

2015-06-25 10.19.56

*Reference to commercial products or trade names is made with the understanding that no discrimination is intended of those not mentioned and no endorsement by University of Nebraska–Lincoln Extension is implied for those mentioned.

9. An email listener wanted to know if fertilizer changes composition over time?

A. Yes, it can break down and become less effective. If fertilizers are stored where they freeze and thaw continually or get moisture into them, they will not work as well as they originally did.

10. A caller has a windbreak that is dying. What are some good tree choices to replace the windbreak with?

A. Cedars, black hills spruce, Colorado blue spruce, Douglas fir, concolor fir, white pine, ponderosa pine, or Jack pine would all be good replacements. Make your windbreak out of a diverse selection of these trees. Don’t go with a windbreak of one tree species.

11. This caller has a peace lily that the leaves turn brown and then die back. It continues to go through this process. It has been repotted but is still exhibiting the damage. What is it and how can it be improved?

A. This could be due to overfertilization or too much salt content in the water. Try using distilled water for a while. It will flush out the salt content from previous water over time. Eliminate the use of any fertilization. It is a common problem in peace lily plants and they should be fine.

12. What chemicals can be used for bagworms and when should they be sprayed?

A. Bagworms are typically active in the third week of June and this would be the best time for spraying. The emergence of the bagworms is weather dependent and it can range from the middle of May to late July. Average years it is the third week of June for the timing of sprays. It is best to just watch your tree and spray when the new bags are 1/2-1 inch in length. You can treat them with general insecticides such as Sevin, Eight, Bt, or Tempo.

fern leaf peony, Lee Ruk Flickr

Photo of fern leaf peony from Lee Ruk via Flickr Creative Commons License

13. The last caller of the day wants to find a fern leaf peony. It seems to be hard to find. Where could she find this plant to purchase?

A. It should be fairly easy to find at a local nursery. Many of the box stores probably will not have this unique and interesting plant.

Yard and Garden: June 26, 2015

Yard and Garden Green Logo

This is the Q&A for the Yard and Garden show for June 26, 2015. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 31, 2015. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Sarah Browning from Nebraska Extension in Lancaster County

1. A caller has a pine tree with needles that are turning brown at the bottom of the tree. What would cause this?

A: There are a couple of common fungal diseases on pine trees, needle blight and tip blight. Both of these diseases will start from the base of the tree and move upward. Depending on the species of tree, it could also be pine wilt, but this disease progresses rapidly, causing death in only a few months. There are fungicides to be used for needle and tip blight, but they are best used in May and June. Neither of these fungal diseases should kill the tree in one growing season. This publication from the Nebraska Forest Service, Diseases of Evergreen Trees, shows pictures of both diseases and pine wilt and goes over treatment methods.

2. This caller has tomatoes that have black specks on the leaves which eventually turn yellow and die, but there are no specks on the tomatoes themselves. She was also curious why it makes a difference to water from below rather than above?

A: This would be a fungal disease called black speck or black spot. It is best controlled through good sanitation practices such as watering from below the plant, removing infected leaves as they are first seen on the plant, removing plants in the fall after the growing season, avoid crowding plants, rotating plants each year in the garden, etc. There is a great NebGuide on Leaf and Fruit Diseases of Tomatoes that will be helpful with many of our tomatoes this year with all of the rains as we are seeing many more leaf diseases. Watering from below the plant helps reduce spores splashing from plant to plant and from the soil to the plant. Watering from below also helps to keep the leaves dry throughout the day and into the night to reduce leaf wetness and humidity in the plant which is conducive to disease development.

3. A caller has a bur oak that is 15 feet tall with leaves that are curled under. What would cause that?

A: This could be herbicide damage from a 2,4-D product. It could also be from aphids or lacebugs. To determine if it is due to insect feeding, look on the underside of the leaves for tiny, green bugs, lace-like bugs, or frass. If it is aphids, they can be controlled with many general insecticides. Lacebugs rarely warrant insecticides as their damage is minimal to the tree. If it is herbicide drift, the tree should grow out of it, depending on severity of damage.

Bagworm

Bagworm

4. Is it time to spray for bagworms yet?

A: They have not yet begun to emerge in Southeast Nebraska. They are behind in their development this year due to the cool spring. They should be emerging in the next week or two. Ensure that the immature bagworms are active on your tree before treating to get best control from your pesticide.

5. Another caller wanted to know if it is illegal to use rainwater in Nebraska?

A: No, Nebraska does not have a law to prohibit the catching and use of rainwater, as some other states do. Rainwater is a good use of extra water to avoid so much runoff and contamination to the water supply. Be careful to not use rainwater on vegetable crops to avoid contamination from non-potable water.

6. This caller has a Kentucky coffeetree that was planted in the right-of-way by the city within the last 2 years. The bottom of the tree has leaves and new growth, but the top of the tree does not. Will it survive?

A: This tree probably is having troubles with establishment or may have been planted incorrectly. Due to this, the top of the tree is not receiving water and nutrients from the roots. It can be pruned back to the growth with possible success. Be sure to watch for a new leader to develop or you may have to start a new one to help it grow taller as the central leader will be pruned off of the tree.

Photo by Howard F. Schwartz, Colorado State University, Bugwood.org

Yellow Nutsedge Photo by Howard F. Schwartz, Colorado State University, Bugwood.org

7. How can nutsedge be controlled in lawns?

A: A product that is specific for use on sedges can be used in the lawn with no harm to the turfgrass. The most commonly used product for yellow nutsedge is Sedgehammer, it should be applied multiple times throughout the growing season, as new plants come up. It is better to spray with Sedgehammer early in the life of the new plant to reduce nutlet production and reduce the size of the plant.

8. A caller wondered when the best time is to prune an oak tree?

A: It is not advisable to prune oak trees during the summer months to avoid chances of getting oak wilt in the tree. The best time to prune oaks, and many of our deciduous trees, would be in the dormant season, such as November.

9. A caller has a fescue lawn that is getting yellow in spots. What would be the cause of that?

A: This year we have faced many days of cool, wet, cloudy weather which is favorable to many turfgrass diseases. This sounds like it is either brown patch or dollar spot disease. Brown patch has tan colored lesions on the leaf blades that have a dark margin around the tan spot. Dollar spot would just be tan spots in the lawn that are typically half-dollar sized but you can see many dollar spots coalesce into one larger spot. As the weather dries out and warms up, the fungus should fade in the lawn, or you can use fungicides in the lawn if necessary.

10. A caller has bindweed in the lawn. What can be done to control it?

A: A herbicide that is just for broadleaf weeds will work on the bindweed and not harm the lawn. Triclopyr is a great choice to use. This is commonly found in brush killer, poison ivy killer, and clover killer in the stores. Make sure that the temperature on the day of application is below 85 degrees Fahrenheit to reduce the risk of harm to non-target plants.

11. A lady has cucumbers that are flowering with no fruits developing. What would cause that?

A: Cucumbers have both male and female flowers on the same plant. Early in the season you may see development in only male flowers with no female flowers to produce no fruit. The female flowers will have a tiny cucumber structure at the base of the flower. This also could be due to low pollinator presence in the garden. Rainy days and hot days discourage pollinators. Give the plants more time, they should begin to produce female flowers and fruits soon. Hand-pollination may also be necessary if it is due to low pollinator presence. To hand-pollinate, take a Q-tip and touch the pollen of all of the flowers.

12. A caller has a clematis plant that is dying back, causing all of the leaves to turn brown.

A: Clematis commonly gets a fungal root and crown rot. If this plant was in a location where water sat this year with all of the heavy rains, it may have caused this fungal disease to occur. Cut the plant back to the ground and see if it will grow back, if not, you will need to replant.

13. This caller has Iris plants that have completed their blooming period for the year. Can these be cut back now?

A: No, all spring blooming plants need to be left, without being cut off, for the remainder of the summer until their foliage turns brown in the fall. This allows the plants to make sugar throughout the summer months to have a starting supply for early spring blooming next year. The flower stalks can be removed after the flowers are done.

14. A caller has patches of clover in the lawn. What can be done for management for the clover?

A: The best time for treatment of clover is in the fall with a Triclopyr or 2,4-D product. At this point, the temperatures are too high for herbicide control without possible harm to non-target plants. Both of these products can turn into a gas and move to non-target plants if temperatures are above 80-85 degrees Fahrenheit, the 2,4-D can volatilize for up to 72 hours. Be sure to mow the clover prior to herbicide treatment to mow off the flower blooms and cause less harm to bees.

15. A caller has grass planted in late March and added more seed later in the spring. She used a starter fertilizer and covered the areas with straw, and now there are brown spots appearing in the lawn. What would be causing that?

A: Brown patch disease is common on young seedlings of tall fescue. Look for irregular shaped tan spots with a dark margin to know if it is brown patch. Bayleton is a good fungicide that may still be effective on this lawn. Also, remove the excess straw to reduce disease problems.

16. That same caller has crabgrass coming up around her trees. Can she use roundup to control it?

A: Roundup can be used around the base of trees with minimal damage to the trees. A better option would be to use a post-emergent crabgrass herbicide such as Dimension or Fusilade.

17. A caller wanted to know if it was allowable to use Grass-B-Gone in their sweetcorn?

A: No. Grass-B-Gone kills all types of grasses, including sweetcorn. Also, Grass-B-Gone is not labeled for use in a vegetable garden.

18. A gentleman has mock orange and bridal wreath spirea. When can these plants be pruned?

A: Both of these plants have just finished blooming for the year so they can be pruned now. Remove no more than 1/4 of the plant in a growing season. This can be done by removing the largest canes at the base of the plant. If it is too tall, you can remove 1/4 of the height, if it is a 4 foot tall shrub you can prune it back to 3 feet tall.

19. A caller wanted to know what to do for management of dandelions in their lawn?

A: Dandelions are best controlled in the fall with a 2,4-D product.