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.

Yard and Garden: July 21, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for July 21, 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: Sarah Browning, Nebraska Extension Educator in Lancaster County

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 wants to know how soon they should spray for fleas outside for an upcoming camping outing?

A. Sprays for fleas will last a couple of weeks, so it would be most beneficial to spray a week ahead of the event. Using a product containing permethrin or bifenthrin would be the best control.

2. A caller has hydrangeas that are healthy looking and green but they are not blooming, why is this?

A. This could be due to a few different factors. It could be that the plant is just slow to bloom this year due to environmental factors. Give the plant time to see if it does bloom. If the lawn surrounding the plant is highly fertilized, it may be that some of the fertilizer got into the rootzone of the hydrangea plants. Lawn fertilizers are high in Nitrogen and will cause the plant to grow nice, large, green leaves without putting any energy into producing flowers. If this is the case, make sure that you stay back away from the hydrangea next year when fertilizing the lawn. Finally, this could also be due to the plants being crowded and needing to be divided to allow the plants room to develop fully and produce flowers.

3. This caller has lilac shrubs that had not bloomed for the past few years but now this year it did finally bloom. What would cause that and how can she ensure that they bloom every year?

A. The fact that they bloomed again this year is hopeful. If lilacs are pruned at the wrong time of the year, such as in the fall or early spring, the buds will be cut off when this is done. However, the caller said she has not been pruning them at all. This could be due to the lilacs getting overgrown and having old, unproductive wood in the shrubs. It might be best to try to do a rejuvenation cutting to start all of the branches off new again. With a rejuvenation cutting, the entire plant is cut off about 6-8 inches above ground level removing all diseased, dead, and weak wood from the plant.

4. When do you divide lilac shrubs?

A. This is a woody shrub and we don’t typically divide woody shrubs due to the way that they grow. However, you can dig up the suckers that grow off the main plant and pull them out and plant them in a new location. The best time to do this replanting would be in later September when the temperatures have cooled off.

5. A caller has mum plants that have leaves that are shriveling up and turning yellow. There is only a couple of the plants on each side of her house out of a large group of mums that are not as full and not doing as well as the others. She hand-waters every day.

A. Watering daily could lead to a root rot. The roots need time to dry out between waterings. If it is a root rot, there is nothing that can be done to fix the damage already done and the plants will likely die.

6. This caller has a Rose of Sharon that is not blooming. It is planted in a location with minimal sunlight, would it be in too much shade?

A. Yes, Rose of Sharon bushes need full sunlight and will not bloom if in too much shade. This fall would be a great time to move it to a location with full sun.

7. A caller has cucumber plants with brown spots on the leaves. What would cause this and how can she avoid it killing her plant quickly like it did last year?

A. This could be a fungal disease common in cucumbers this year such as anthracnose or alternaria. Fungicides are not usually recommended in home vegetable gardens because they are typically not necessary or worth the time and money. However, if this disease quickly killed your plants last year, you could spray them with a liquid copper fungicide to keep the disease from spreading this year and killing your plants again. If they died quickly, it could also be from squash vine borer or squash bugs which can kill a plant almost overnight. Spray with a general insecticide for these insects such as sevin, eight, or bifenthrin. Wait the proper amount of days after spraying chemicals before harvesting vegetables. This time will be on the label as the PHI, or post-harvest interval.

8. This caller has a cherry tree that has a white fungus growing out of the trunk of the tree. There are no leaves on the branches in the middle of the tree and it hasn’t produced any fruit this year. What is wrong with the tree?

A. This is a shelf fungi, also called conks, appearing on the tree. Shelf fungi are the outward appearance of interior decay within the tree. When shelf fungi appear on the tree, the tree is dying and should be removed.

9. A caller has a burning bush that is growing up against the deck and some of the branches are dying in the center of the bush. Can it be pruned to remove the dead wood and to cut it back so it doesn’t block the deck? If so, when can it be pruned?

A. You can remove dead branches anytime, healthy branches should be pruned back in the late fall to late winter. The branches may be dying out due to scale insects which can get on the branches and reduce the vigor in the branches they are living on. If you find scale insect, use a systemic insecticide such as one containing imidacloprid in the early spring.

 

Dog vomit fungus

Dog Vomit Fungus

10. This caller remulched their garden this spring with a wood chip mulch. Now there is a cream colored substance on the mulch that looks like cat vomit, but they have no cats. What is this?

A. This is dog vomit fungus. It is a fungal structure much like a mushroom or puffball. It is not harmful to the plants or the mulch. It can be found on mulch because it lives on decaying organic matter such as the woodchips. It is nothing to be worried about and if you don’t like the way it looks, you can wash it off with the jet setting on your hose end sprayer.

11. A caller has a prairie area where he is trying to grow a mix of wildflowers and native grasses. However, Marestail is growing in among the desirable plants. How can he control the broadleaf weeds and not kill his desired broadleaves and grasses?

A. Once the grasses and wildflowers thicken up in the prairie, they will push out the weeds, but establishment is the hardest part. Mowing this year will help to thicken up the plants growing there and will stop seed production in the marestail which is an annual weed.

12. This caller is also starting a prairie area. He has had a 2 acre pasture of alfalfa that he now wants to change over to native grasses. What is the best method of doing this?

A. The native grasses are mostly warm season grasses, so they are best planted in the end of May to the beginning of June. Dormant seeding could be done in late November, but you need to prepare the area this fall before a dormant seeding is done. To prepare the soil, kill the existing plants this fall and clean up and aerate the soil prior to planting. You can drill the seeds in when the time comes as well.

13. A caller has an area where soil was added and leveled off. How do they overseed the area that has been overtaken by weeds at this point?

A. Spray the area with roundup to kill the weeds. You can spray now and again shortly before seeding the area. Then overseed in September with a Kentucky bluegrass or Turf-type tall fescue. Once you overseed, use a rake to get the seed to contact the soil and keep it well watered.

14. This caller has an oak tree that is not fully leafed out, the top is bare and the lower leaves are smaller. What is wrong with the tree?

A. This could be due to herbicide drift since many neighboring trees look similar. If so, there is nothing to do to fix herbicide drift once it has been done, just make sure the tree is being watered and that it is mulched in. This could also be due to the fact that the tree isn’t getting enough deep water if it is just being watered by the turf irriagation. Make sure that once every 10-14 days a slow, long irrigation is done around the tree. Trees need water down to 12-18 inches deep, lawn irrigation only waters the top 4-6 inches of the soil.

15. A caller has 2 large Norway pines. How can he get grass to grow under the trees?

A. Unfortunately, grass will not grow in heavy shade under a large tree. It would be best to try a groundcover, sedge plants, or shade perennial plants. We often continue to battle grass problems and overseeding in heavy shade, but the reason the grass won’t grow is because it is not meant to be grown in shade. In these situations it is best to find other plants that are more suited to the shade or just mulch around the tree to stop weeds from growing around the tree.

16. The last caller of the day has dwarf lilacs that are quite large. How tall are they supposed to grow?

A. Dwarf lilacs, such as the Miss Kim variety, will still grow up to 6 feet tall if left unmanaged. This is still much smaller than the full sized-lilacs which grow up to 15 feet tall. You can continually prune these lilacs in the spring after they finish blooming to keep them to a smaller size. Prune within the couple of weeks after blooming so you don’t cut any flower buds off.

Yard and Garden: July 14, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for July 14, 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: Steve Karloff, District 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 overgrown Forsythia and Yellow Dogwood plants. What can be done for pruning to reduce the unproductive plant materials and when can it be done?

A. Because these plants are overgrown, it would be most beneficial to do a rejuvenation cutting on them. A rejuvenation cutting is when you prune a shrub back to about 6-8 inches from ground level and remove the majority of the top growth. This will get rid of all the old, unproductive wood to bring in all new, younger wood that will be more productive to leaf out better throughout the entire shrub, will lead to more flowering, and will be healthier and free of insects and diseases that were problematic on the shrub. It is best to prune forsythia immediately after they flowered, but it could be done in the fall. Remember with a rejuvenation cutting that the plants will not flower for at least 2 years following the heavy pruning.

2. A caller has blue spruce trees planted in an area near a lake. Some of the spruces are 60 years old and some are 15 years old, all are dying from the bottom up. What is wrong with these trees?

A. Too much moisture can cause blue spruces to die from the bottom up, since they are planted close to a lake, they may be getting too much watering. When replacing the trees, choose a species more adapted to wet locations such as white pine, cedars, or bald cypress.

3. This caller has a green apple tree that was planted before he moved in and the apples are falling so they are ripe. The apples are not juicy and are quite porous and pithy. What is wrong with the apples?

A. After discussions on this with Paul Hay, this is just the variety of apple that is growing there. This is an apple that is used more for processing to be used in pies and sauces and not for fresh eating.

4. A caller has rabbits that are eating her hostas and lilies. What can be done to control them?

A. The only effective management for rabbits in a garden is to put up a fence that is at least 2 feet high.

5. This caller has a bur oak that was planted in the spring. The old leaves on the tree are turning brown but the new growth is green and healthy looking.

A. Be careful to not overwater a tree, especially with newly planted trees. These young trees have a small root system and do not need to be watered as heavily as an older, established tree. It is beneficial to allow the roots to dry out a little between waterings.

6. A caller has white pines that were planted too close to the driveway and now the branches hit cars when they come to park in the drive. Can the branches be trimmed back so they don’t hit cars and when can that be done?

A. Yes, these branches can be removed. Take the branch all the way back to the trunk so that they don’t regrow causing pruning to be necessary every couple of years. You can prune evergreens most any time of the year.

7. This caller has a bur oak that was planted last fall. It didn’t come out of dormancy this spring and has not grown. However, there are suckers coming up at the base of the tree, can the main tree be pruned out and the suckers allowed to grow into a new tree?

A. Yes, remove the main tree and allow one of the larger more upright suckers to grow into a new tree. However, sucker growth is not always as strong as the tree itself, so it may not perform how the tree was supposed to.

8. Can lilacs be pruned now?

A. No, it is best to prune lilacs within a couple of weeks after they are done blooming. Lilacs produce their flower buds in the summer and fall of the year before they bloom, so pruning now would cut off the flower buds for next spring. To ensure flowering for next year, wait until after it blooms next year and then prune it back at that time.

9. A caller has cypress trees that were planted 5 years ago. One of the 2 trees is in great condition with good color. However, the other one is smaller and yellow in color. The trees are only a few feet apart. What is wrong with it and can it be fixed?

A. The yellow and shorter tree may have just been a bad tree out of the gate. Sometimes our trees develop a problem in a nursery or from the seed source and never really overcome that. Also, with Bald Cypress trees, it is hard for them to overcome iron chlorosis. When these trees get iron chlorosis, they become stressed and no matter how many trunk injections, which also harm the tree, they never come out of the chlorosis. At this point, it would be best to remove and replace the bad tree.

 

Summer Patch at Christenson Field, P Hay

Photo of Summer Patch from Paul C. Hay, Nebraska Extension Educator

10. This caller is having problems with their lawn. He fertilized it in May but now it has brown patches throughout. How much water does a lawn need and how can he improve his lawn?

A. Our lawns need 1-1.5 inches of water per week on average to stay green and out of dormancy. The patches could be the lawn going dormant or they could be from a fungal disease. There are a lot of summer fungal diseases such as brown patch, summer patch, and dollar spot. They are common in the hot and humid days in late summer but as soon as that weather fades, the brown spots will turn green again. For more information on these diseases, see this TurfiNfo from UNL.

11. A caller has Bradford pears that have branches coming out 1.5 feet above the ground, should those be removed or will they move up as the tree grows? The trees also have suckers, what should be done about that?

A. If these low branches are in the way for mowing and you don’t like how low they are, they should be removed. Remember not to remove more than 1/4 of the tree in one season, so you may have to remove one this year and another next year. Those branches will always be at that level, though, so if they are in your way they need to be removed. As for suckers, cut those off at ground level and don’t treat them with anything or the spray will kill the tree as well.

12. This caller has pumpkins in his garden that are wilted during the day but at night they look fine. What is wrong with the plants?

A. If a plant looks better in the evening or in the morning but is wilted during the hot part of the day, it is heat or water stress. Make sure your plants are properly watered through this hot and humid couple of weeks of the summer.

13. A caller has tomato plants with leaves that are drying up from the bottom of the plant. The tomatoes are also rotten on one end of the fruit. What is causing these two problems?

A. Ensure that the plants are being properly watered. Vegetable gardens need 1-1.5 inches of water per week. Hand watering at the base of the plant every night is not sufficient for the root system. The plant could also be exhibiting early blight which is common right now. Remove the infected leaves, the disease will fade soon. The rotten side of the fruit is blossom end rot. This is a calcium deficiency in the plant caused by uneven watering making the calcium unavailable to the plant. Adding calcium to the soil will not help the problem, just make sure your plants are well watered and mulched in. Blossom end rot will fade soon. You can eat the good side of the fruit and dispose of the rotten end.

14. This caller has round berries on the plants of her potatoes. What are these?

A. These are the fruits of a potato plant. We typically do not see the fruits because we are growing the plants for the tubers produced underground and we harvest before the fruits appear. Remove the fruits so the plant can build the tubers.

15. A caller has roses that have uniformly round holes on the edges of the leaves and brown spots. He sprayed with rose spray and it is not working. What is wrong with the plants and how can he fix it?

A. This is likely damage caused by the leafcutter bee which is a pollinator and beneficial insect. There is no need to control this insect. Here is a great article from Jonathan Larson, Nebraska Extension Entomologist, on Leafcutter Bees.

16. How do you control puncturevine in a lawn?

A. Use a 2,4-D product in the pre-bloom stage. Management will not be achieved this time of year because the plant is large and will be difficult to kill. Also, don’t use 2,4-D products in the heat and humidity of the summer or the product may move to non-target plants causing damage.

17. How do you control moss in a pond?

A. Copper sulfate crystals can be used for control. For more information on pond management, visit the Lakes, Ponds, and Streams section of the water.unl.edu website.

18. A caller has apple trees that get insects in the fruit every year. When and what should they be spraying for that?

A. It would be best to get on a spray schedule, spraying with an orchard fruit tree spray every 10-14 days throughout the growing season. For more information visit the Local Food Production page within the food.unl.edu website for spray guides.

19. The last caller of the day has vines with milkweed type pods growing in his fenceline. What can be done to control it?

A. The plant sounds like honeyvine milkweed. At this point of the year, pull it or spray it with roundup. In the spring or fall, 2,4-D could be used, but not now due to the heat and humidity.

 

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.

Do prune this…Don’t prune that

2013-05-09 10.12.37

Spring will be here before we know it. With all the warm weather lately, it is hard to remember that spring has not already sprung in Southeast Nebraska. But, with the warmer weather, there are a few things we can do in our landscapes and a few things we should avoid.

Don’t prune spring blooming shrubs this time of the year. Plants such as lilac, forsythia, spring blooming spirea, and some hydrangeas produce flowers in the fall of the previous year to bloom early in the spring. If you prune these plants now, you will cut of the flower buds and not have those flowers to enjoy this spring. So avoid pruning those shrubs in the spring. Spring blooming shrubs should be pruned immediately after they finish blooming in the spring. This will allow for the best growth of the plant and for best flowering each year.

Forsythia-Richard Elzey, Flickr

Forsythia Flickr image courtesy of Richard Elzey per CC license

Prune trees this time of the year. February and March are the best months of the year to prune deciduous and fruit trees. It is best to prune these trees during the winter months because it doesn’t affect fruiting that occurs in the spring and it allows the tree to seal up the wound quickly in the spring when growth resumes. It is also easier to see areas that need to be pruned in the winter months. You can see where branches are crossing or rubbing and where the branches are too dense. In addition, pruning in the late winter helps reduce the transmission of different diseases that aren’t active. However, it is best to avoid pruning maple, willow, poplar, birch, hackberry, Kentucky coffeetree, black walnut, honeylocust, and elm due to the high sap flow they have in the spring. Freshly cut wounds this time of year will cause the tree to “bleed” or have excessive sap flow out of the wounds. They are best pruned in the late summer to early fall to avoid sap flow.

Don’t uncover perennials yet. It is still winter, for a few more weeks. Many of our perennials are getting confused with the weather lately and some are starting to green up already. Tulips, Iris, and peonies are starting to emerge and crocus are blooming already. However, if you pull the winter mulch back from these plants or remove the plant material that was left on the plants through the winter, you will be exposing the plant to cold temperatures and removing its protection. The plant will have better survival and less winterkill if you leave them covered through the winter months.

Plan your gardens for the spring. Late winter is a great time to plan what you will plant in your vegetable gardens so you can format your plan to know what you have space for and to ensure that you move your crops around from year to year. This will also help you decide what seeds to start indoors. Mid-February through March is a good time to start the seeds of your chosen warm season crops indoors. Make sure that you have them in a warm location with 14-16 hours of light on them everyday.

crabgrass, Joseph Berger, Bugwood

Crabgrass photo is courtesy of Joseph Berger, Bugwood.org

Don’t use pre-emergent herbicides for crabgrass yet. The soil temperatures have been at an average of 40-45 degrees Fahrenheit over the past 7 days. Even as warm as it has been, crabgrass has not yet begun to germinate. If the temperatures continue at this pace, it will probably germinate early, but we still have a couple of weeks before we need to get the pre-emergent herbicides on. Remember, crabgrass germinates at 55-60 degree soil temperatures, so we still have a bit of warming up to do.

Gardening Tools

garden-tools-blog

January and February are great months to start thinking about gardening again, but don’t get too excited, there is plenty of winter left before we can go out and start cleaning up our gardens. However, we can start thinking about what we can do in our gardens this year and inventory garden tools to determine replacement and new pieces.

Garden Gloves are essential for any gardener. They help keep your hands from getting torn up when pruning roses or other plants with thorns. Garden gloves also keep you from getting dirt caked onto your hands. In my case, my gloves give the pruners something else to hit before cutting my finger, which is why there is a hole in my current pair. I have a very nice pair that are breathable and have a nitrile covering over the palm and fingers to keep my hands protected when working in the garden. I have to have a pair that fits tightly to my hand and that breathes or I will not wear them and then I will have very rough, callused hands with many scratches and wounds. My garden gloves are a must in my garden bag.

gardening-gloves

Every gardener needs a good selection of pruners. Hand pruners work best for pruning small branches on many of our shrubs and to cut back herbaceous perennials. Branches cut with hand pruners should be less than ½ inch or less in width. They also work well for deadheading during the summer months. Bypass pruners are preferred to the anvil type of pruners because they are less damaging to the plant stem when pruning. The anvil type of pruners crushes the stem as it cuts and can harm the plant.

anvil-vs-bypass-pruners-michigan-state-univ

Photo of pruner types is from Michigan State University

Long-handled loppers are great for making pruning cuts on medium-sized branches, those that are ½ – 2 inches in width. There are many choices in your lopper purchases. Some have a standard length and some have telescoping handles, allowing them to be used higher into the tree or deeper into the shrub. Just like with the hand pruners, the bypass loppers are better than the anvil type.

For larger pruning jobs, a handsaw will be necessary. Again, there are many different types of handsaws you can purchase. I prefer the folding type which is safer and easier to transport because it fits nicely in my gardening bag.

A good spade is necessary for gardening. I prefer to keep a hand spade nearby for small jobs like planting vegetables and annuals and a long-handled spade for larger jobs such as planting trees and shrubs and to dig up large plants for removal or to divide. There are 2 main types of spades to use in the garden, the rounded spade and the flat spade. The flat spade is good for edging a garden and to get weedy growth off of bricks and edging each year. The rounded spade is good for digging into hard soil and for planting. I like some of the shorter handled rounded spades with a good point on the end. One particular model I like is the spade with an arrow-shaped head on it. This model moves through the soil much easier than some of the other spades.

One final tool that is very helpful for the avid gardener, would be a garden hoe. I have a hand-held Japanese sickle that I prefer to use. I can swipe it through the garden between my plants and it pulls up and cuts off all the weeds in your garden. You can even use this for weeds growing up through the mulch. You may have to move the mulch back a little after going through for weeds, but it is very quick and easy to use.

weeding-sickle

Japanese Weeding Sickle

So get out your gardening books and find what works best for you and restock your garden tools.

Yard and Garden: July 8, 2016

Yard & Garden for blog

This is the Q&A for the Yard and Garden show for July 8, 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: Dr. Paul Read, Viticulture Specialist for Nebraska Extension with Guest Intern Vivian from China

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 caller of the day wanted to know if they can prune the Cleveland Pear tree that has branches that are low and too tight to the trunk?

A. The best time for pruning a tree like this would be while it is dormant. For a situation like this where the caller is only removing a few branches to help with the growth of the branches and to reduce future problems with the tight branch arrangement it would be fine to remove them now. It would be better to remove branches like this before they break in a storm due to weak attachment to the trunk.

2. A caller has Anjou pear trees that were planted in 2013. Now the bark from the graft union up about 10-12 inches has the bark peeling and now has some black leaves. What would cause this?

A. This would be from sunscald. There is no way to fix sunscald once it occurs. Don’t paint the wound with anything, allow it to heal itself. The black leaves could be due to fireblight. You can cut 6-8 inches past the diseased portion of the limb to cut the fireblight off the tree. The black could also be anthracnose which is not damaging to the plant and there is no need to spray anything for anthracnose.

sunscald-bugwood

Sunscald Photo by William Jacobi, Colorado State University, Bugwood.org

3. This caller has an oak tree that is dripping sap on the vehicles parked under it. What would cause this?

A. Aphids feeding on the leaves of trees will excrete honeydew that can drip on vehicles underneath the tree. Aphids are not very damaging and have a lot of predatory insects that feed on them. They can be sprayed with sevin or eight or another general insecticide, but they should fade out on their own with predator insects.

4. A caller has blue spruce trees that look dirty but the tips are still green. What would cause this?

A. This is most likely due to environmental stress from the heat and humidity. If the ends of the branches are still green, the tree will be fine. Make sure your tree has a mulch ring around it and that you keep it well watered in the heat of the summer.

5. This caller has a patch of lilies where a quarter of the patch has only grown to be about 6 inches tall for the past 2 years. The rest of the patch looks good, but this area doesn’t look healthy. Can these be improved?

A. This could be due to hardiness in some varieties that are only suitable for our environment for a couple of years. It also could be due to some bulb mites. It would be a good idea to dig up some of the bulbs to see if they have any damage on the bulbs.

6. A caller has a pine tree with a lot of sap on the branches and the grass in the lawn won’t green up. Why is this?

A. Woodpeckers or insects feeding on a pine tree can cause sap to leak from the wounds left behind. The insects can be controlled with bifenthrin or permethrin (eight). If it is woodpeckers, the damage is minimal and will not cause any problems to the tree. Check how much water the lawn is actually receiving by using catch cans during the water intervals normally followed. Lawns need 1 1/2 inches of water per week. If the water is fine, there are a lot of fungal diseases in the lawn, it could be one of those. Fungal diseases in the home lawn are usually sporadic and therefore don’t require fungicide applications.

7. This caller lives on an acreage surrounded by farmground. She is considering growing grapes on this large plot of land. Are grapes easy to grow and would grapes have a benefit to the wildlife in the area?

A. Grapes are a large commitment, especially if you plan to sell products from them. You can be successful with only a few plants for the family to use for grape production. A few good choices for this area would include Frotenac or Valiant. The first year the grapes would need extra care, but after that they would be more self-sustaining. Deer will feed on the foliage. If you decide to grow your grapes for commercial use, register  your acreage with the driftwatch website at  www.fieldwatch.com to help avoid problems from drift since grapes are very sensitive to drift damage.

8. A caller has strawberries that were planted and now have very small fruits and the plants are not making runners.

A. Everbearing strawberries are typically very small for fruit size. You might try planting some newer varieties that are June bearing to get larger fruits. Some good choices would include honeoye or albion or sparkle.

9. This caller has an ash tree that is 7 years old and the tree snapped off in the wind. There is mold in the trunk and it is suckering. What can be done to plant a new tree?

A. You can get a company to come in and grind out the stump or rent a stump grinder to do it yourself. The suckers that keep growing back will continue to for a few years, they can be cut out and treated with a roundup or 2,4-D product. You can plant a new tree within just a few feet of the old tree, since this wasn’t a very large tree yet.

10. A facebook photo came in with a odd structure that appeared by a tree. What is this?

A. This would be a stinkhorn fungus. They are not harmful to the plants growing in the area. There is not control other than mechanical removal of the fungus. Do not eat these as they are not edible, they would be a poisonous mushroom.

DSCN6327

Stinkhorn Fungus

11. The last caller of the day has tomatoes in a raised bed. When they ripen for harvest, the end of the tomato seems blighted. What would cause this?

A. This is blossom end rot. It is a calcium deficiency that develops in our plants in drought situations because calcium is only available to plants after it has been dissolved in water. There is no control for this, it should only last for a few weeks early in the growing season and then the plants should grow out of it.

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.

Yard and Garden: June 19, 2015

Yard and Garden Green Logo

This is the Q&A for the Yard and Garden show for June 19, 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: Dick Campbell from Campbell’s Nursery in Lincoln, NE

1. A walk-in guest has ants in her house. How can they be controlled?

A: Liquid ant baits work best. One good choice is the Terro bait stations. Another helpful tip is to spray around the outside of the house on the outside of the wall where most ants are found. The little black ant and odorous house ant are common in homes right now.

2. A caller has Linden trees that are covered with moths right now. What can be done to reduce the populations for outdoor activities?

A: A contact insecticide spray will work for the moths, such as malathion. These products do not have a very long residual, so they need to be reapplied. However, be very careful with insecticides on linden trees and other flowering plants to not harm bees and other pollinator insects. Spray at dusk to avoid spraying the bees.

3. A gentleman has a snowball bush viburnum that just finished blooming for the spring, can it be pruned now?

A:  Now that the blooms are fading from a spring bloom, it would be a great time to prune the shrub. It is best to remove the largest canes of the shrub all the way back to the ground, up to one-third of the plant in one growing season. Leave the rest of the canes as they are or remove a portion of their height, if necessary.

4. A gentleman has moths in large populations on his “bug zapper” every morning. Is he bringing the moths in? Should the “bug zapper” be moved from near his plants?

A: Moths are attracted to lights, but you aren’t bringing them in from far distances. You can move the “bug zapper” if it is near a regularly used door that causes problems with moths when going in and outside. They are not causing any harm to our plants.

5. When is the best time for grub control? And, is it past the time for crabgrass control?

A: Grub control is best done right now, during the third week of June. It is best to apply grub control when the adults are actively flying and mating. Crabgrass is still germinating, so crabgrass control can still be applied if none was applied earlier in the spring. If you do a split application of crabgrass control, now is a good time to do the second application for the spring.

6. A caller has a spruce tree that has been slowly dying for a couple of years, it has now lost 60-70% of its needles. If they remove the tree, will something else grow where that tree is removed?

A: Yes, the stump will cause no problems to a new plant. You may want to plant the new tree 5-10 feet away from the stump to avoid the root system, but otherwise no problems will occur. The needles on the ground may lower the pH of the soil, but in a clay soil, the amount is so low to cause no problems if not help the plant.

7. A caller is moving from one house to another. The house they are leaving has a great asparagus patch. Can that be transplanted to the new home?

A: It is best to move asparagus in the fall when it is going into dormancy. Asparagus will transplant well, but you will need to wait until the third season after transplanting before heavy harvesting can resume. A new plant would take the same amount of time and may be better suited for a moving condition to ensure it is planted at the correct time of the year.

8. A gentleman has a crabapple tree that he removed from a landscaping berm. Can he use Tordon on the stump to keep it from regrowing?

A: No! Tordon is not labeled for use in a landscape setting so it should never be used in a lawn or garden. This product can move out into the root system of other plants and it has a residual for up to 5 or 6 years where it can still cause problems to the neighboring plants. Be sure to always read and follow label instructions on all pesticides as the label is the law.

9. A caller has sweet corn that is tasseling but it is only 3 feet tall. What would cause this?

A: Some hybrids of corn are shorter. If that is not the case, it would be due to environmental stress. When a plant is stressed they may try to produce fruit sooner than they should for the size of the plant.

10. A gentleman has a 60-year-old spruce tree that is dying on the west side of the plant. What is causing this?

A: Look for white sap on the trunk which would be an indication of canker. This is likely due to environmental stress from the quick drop in temperatures last fall. Any branches that are dead can be pruned off and it should regrow new branches eventually.

11. A lady had a birch and 2 large maples planted last fall. This spring the birch is slow to leaf out and still has not leafed out on the top of the plant. What is causing this?

A: Birch trees face a lot of death in the first year after being transplanted. Scratch the bark of the branches to see if their is any green, live, growth or if it is brown and therefore dead. If it is brown, call the nursery to get a replacement tree planted.

12. Another caller also has 2 maples that were planted last fall and are dead on top. What is causing that? She also has hollyhock rust, is that too early to be seen?

A: They didn’t get enough root growth developed prior to the drop in temperatures last fall. If they have no green in the cambium layer, the caller should call her nursery for a replacement tree. As for the Hollyhock rust, that is due to the rainy weather we have seen this spring.

13. A caller has blue spruce trees that had flood water up and around their bottom branches for 2 days and are now turning brown. Will the trees come out of this?

A: Spruce trees don’t like too much moisture. However, don’t give up yet, give them time to come back and grow out of the problems from flood damage. It is too early to tell if these are long-term issues for the plants.