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.

Storm Damage to Trees

2017-06-15 19.43.56

This time of year, storms tend to sneak up on us, as we saw last Friday night. Unfortunately, some of those storms can be severe and cause damage to us, our homes, our vehicles, and even our trees. When storms bring strong winds, hail, and tornadoes, these things can all do different kinds of damage to our trees. Cleanup doesn’t end with the branches on the ground.

2017-06-20 09.26.08

If heavy winds come and break branches, those breaks need to be cleaned up to a good pruning cut to allow the plant to seal up the wound. If the storm broke the top out of the tree, it would be a good idea to get a Certified Arborist in to look at the damage to determine if the tree can be salvaged. Allow the Arborist to do the pruning because there are methods that can be done to start a new leader in the tree to help it fill back in and continue to grow upward.

2017-06-20 09.26.52

In addition to branches breaking, some of these trees may have even had bark ripped all the way down the trunk of the tree. When trees have open wounds that are large, it takes a long time for the tree to seal up that location, if it can ever be done. This is a great location for insects and diseases to come into the trees and cause secondary effects on the trees. Unfortunately, there is nothing that can be done to “fix” this type of wound. It is best to just leave it alone and let it heal on its own. You can remove excess bark that is hanging off the tree, but don’t paint or wrap the wound with anything, this can hinder the sealing process of the tree.

Hail can cause damage to the leaves and bark of our trees. If your trees leaves look ragged and ripped due to hail, it is mostly aesthetic damage. The leaves are still on the tree and able to produce sugars through photosynthesis for the trees so it isn’t as damaging as it looks. Damage to the bark on the trunk and on the branches can be more problematic, unfortunately there is nothing that can fix this but time. You will always have round-to-oval shaped wounds where hail hit the tree, but over time the tree will seal these wounds and it won’t be too problematic. If there are a lot of large hail wounds to a small tree, it might be the demise, but give it time to see if it pulls through. For a second opinion have a Certified Arborist look at the tree.

Some trees were uprooted in these high winds. According to John Fech, Kathleen Cue, and Graham Herbst from Douglas-Sarpy County Extension, the younger the tree is, the more chance it has to survive storm damage that caused it to lean. If the tree is 0-5 years old, it has a good chance to survive leaning and should be staked as soon as possible, as long as it is not closely located to people or property. If the tree is 5-10 years old and is leaning, there is a 50 percent chance that the tree will survive. Consult a certified arborist to determine the survivability of that tree, as the degree of lean is what will cause the tree to live or die. If the tree is more than 10 years old and is leaning, it becomes a hazardous tree. If that tree is in an area where it is in close proximity to people or properties, it should definitely be removed. However, if this tree is on an acreage or farmstead and is further away from people or property, it may be able to survive in that location, but a certified arborist should still be consulted to know for sure.

Yard and Garden: June 16, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for June 16, 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 from UNL 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 caller of the day has a Daylily that has yellow streaks on the leaves. What is causing this? She also has Roses that are getting yellow leaves and sprayed a rose product containing both an insecticide and a fungicide. Will this work for the roses?

A. The daylilies likely have Daylily Leaf Streak, a fungal disease common on daylilies. It would be best to remove the infected leaves and destroy them from the plants as you see them and clean up the plants in the fall by cutting off all the foliage and destroying it for winter. It will also help to water from below the plants rather than using an overhead sprinkler. Also, it sounds like her daylily plants are overgrown, this fall it would help to dig and divide them to increase air space. As for the roses, they could be dealing with black spot or rose slugs. The fungicide and insecticide combined product will work to reduce the incidence of both of these problems.

2. A caller wants to know when the best time to transplant asparagus and what can be done for a cypress tree turning yellow?

A. Asparagus is best planted and transplanted in the spring. However, if this is an old patch of asparagus, it would be better to just start from new crowns. Either way, you need to wait 3 years to harvest to allow the roots to develop. Trees that turn yellow instead of their deep green color through the growing season are often lacking iron. The best management for Iron chlorosis is to use a trunk injection of iron. However, with cypress trees, it is often difficult to get them out of this condition and multiple years of trunk injections can start to stress the tree out to the point of death in some cases.

3. This caller has peonies and moonflowers in her yard and wants to know when the best time is to transplant them and how to prepare the area that was rocked to get these plants to grow well?

A. Spring will be best for establishment, but fall would be a second best option to transplant these plants. Remove the rocks that were in the new location and then till the soil, adding compost in as you till to improve the structure of the soil and add some nutrients back into the soil. When moving peonies, make sure that it is planted at the same depth in the soil, to deep and the plants will not flower. After you have planted, add some wood chip mulch around the plants to help them stay cool and hydrated. Water as needed.

4. A caller has a large blue spruce that has some browning on the needles and those needles are beginning to fall off the tree. This has started at the bottom of the tree and is moving upward through the tree. What is causing this? Can her tree be saved?

A. This could be one of two things, either a fungal disease or spidermites. After discussion, the caller stated that the needles are more of a reddish brown, which is distinct for a fungal disease called Rhizosphaera, which is common now. The trees can be sprayed with a fungicide to reduce the spread of the disease. Over time, the trees will grow new needles.

5. This caller recently planted 2 new 7-feet tall blue spruce trees. They are watering these trees at least once a week for 30 minutes and they are mulched in with straw. Now, the lower branches are droopy and wilted. Do these branches need to be removed?

A. These trees are dealing with transplant shock and need some time to build some new roots and get over the shock. Leave the branches for now and continue to water as needed.

6. A caller has a volunteer tomato plant that is about a foot tall. Can it still be transplanted now to be grown in the garden?

A. Yes, it will still be fine. The volunteer tomato will not come true from seed, so it may not be the same type of tomato as what was planted last year, but it should grow fine.

7. A caller has a bald cypress that has needles that are curling. What would cause this?

A. This sounds like drift from 2,4-D or another type of herbicide. This would happen if people are spraying these herbicides now that the temperatures have risen so high. Slight damage may be only aesthetic this year. Multiple years of damage can start to cause stress and even death to the tree.

8. This caller is growing grapes in his backyard. These grapes have black spots on the vine that the caller sees most years. The grapes then shrivel up before they can be harvested. What would cause this?

A. This sounds like a fungus. It would be best to get on a fungicide schedule with your grape plants to keep this fungus from returning every year. For more information on when and what to spray, view the Midwest Small Fruit and Grape Spray Guide

9. How do you stop zoysia grass from spreading in Tall Fescue and Kentucky Bluegrass?

A. Fall fertilization will push zoysia to grow when it is going dormant because it is a warm season grass. This fertilization will be beneficial to the cool season grasses.

10. A caller has Canna bulbs. Is it too late to plant them yet this year?

A. They can plant them to keep them alive and get sugars built up for next year, but they will likely not bloom this year. Cannas have to be dug up and stored indoors over the winter and if they are left out of the ground for 2 seasons, they may not have enough energy to grow after that. Planting the bulbs this year to get sugars for growth next year would be the best place for them to be stored.

11. This caller has patches of round grass in the lawn. How can it be controlled?

A. This is likely a perennial grassy weed such as windmill grass, orchardgrass, or quackgrass. These can be controlled with roundup and then overseeding or with a mesotrione product such as Tenacity. For more information on these weeds, view this article from Lancaster County Extension.

12. A caller has a spirea bush with dead wood in it. Can it be cut back now?

A. Yes, this isn’t the best time for a summer blooming spirea, but it will be fine. Summer blooming spirea’s should be pruned in the late winter, such as February and March for best blooms. This can be pruned back to 6-8 inches from the ground. However, if it is a 50 year old plant, as the lady stated, it may be getting old and may not return from a rejuvenation cutting as it may be dying due to old age.

13. How do you get rid of poison ivy which is growing in rose bushes?

A. It will be difficult to remove the poison ivy and not harm the roses or not get a medical reaction from the poison ivy while working to remove the posion ivy. Paint roundup on the leaves of the poison ivy now, being careful not to get the glyphosate on the roses. It may take multiple applications to kill the poison ivy entirely. Wear long pants, long-sleeved shirt, gloves, socks, and shoes when applying this to avoid getting a rash from the poison ivy.

Poison Ivy-David J Moorehead, Univ of GA, Bugwood

Photo of Poison Ivy courtesy of David J. Moorhead, University of Georgia, Bugwood.org

14. This caller has a trumpet vine that is creeping into the lawn. How can it be controlled in the lawn without damaging the parent plant?

A. Just keep mowing it off. These are likely runners from the main plant and if a pesticide is used to control the runners, it will go through the plant into the roots of the main plant.

15. This caller is curious if poison ivy oils can transfer to pine cones on the ground surrounding the poison ivy plants? She is also curious if she can trim her Iris plants back now or if she has to wait until the fall?

A. According to Clemson University, the poisonous oils can remain active for months on objects. It can be picked up on tools, clothing and the fur of pets. Anything that may carry the oil should be carefully washed. Even dead plants or roots may cause allergic reactions for a couple of years. So it is best to clean the pine cones that came in contact with the poison ivy. For more information, see this guide from Clemson

As for the Iris plants, you need to wait until fall to cut the leaves back when the leaves turn brown for the year. It gives the plant time through the summer to build up sugars to help bloom early next spring.

16. What type of tree would be recommended that is smaller but provides good shade?

 

A. Dwarf Chinkapin, Pawpaw, Redbud, Crabapple, Serviceberry

EAB: What to watch for??

EAB

Photo by Leah Bauer, USDA Forest Service Northern Research Station, Bugwood.org – See more at: http://www.insectimages.org/browse/detail.cfm?imgnum=5473689#sthash.6HVDSdAf.dpuf

Emerald Ash Borer, EAB, is an invasive insect that was first found in Nebraska in the summer of 2016 when it was found in Omaha and in Greenwood Nebraska. Previous to this discovery, EAB was found in Missouri, Iowa, Kansas, and Colorado for the closest confirmed presence of this insect to Nebraska. Now that it has been found in Nebraska, there are more concerns for the residents.

One of the common calls I have received lately is determining if a poorly growing ash tree is infected by Emerald Ash Borer or if the insect on the tree is an Emerald Ash Borer beetle. It is hard to determine by looking at the tree if it is infected by EAB, but there are some signs to look for on your tree.

The signs of EAB infestation include suckering at the base of an ash tree, decline in the tree from the top of the canopy downward through the tree, 1/8 inch D-shaped exit holes along the trunk and branches, increased woodpecker damage, S-shaped Serpentine galleries underneath the bark of the tree. One of the first signs is that the tips of the branches will be bare of leaves. If you notice any of these symptoms in your ash tree, you should contact your local Nebraska Extension Educator.

EAB Damage Collage

As for the beetle itself, which would be flying as an adult now, it is a ½ inch long metallic green colored beetle. It has a bronze-purple color under the elytra. Elytra are the hard wings on a beetle. There are a lot of green colored insects that are often confused with EAB. There are tiger beetles, Japanese beetles, Green June beetles, green ground beetles, green stink bugs, and many other green borer beetles.

EAB Look-Alikes Chart -3200px - Updated May2017

If you find any green bug on your tree make sure you bring it to your local Extension Office. The best way to transport insects is to scoop them up and put them into a zip-top baggie or old pill container or old sour cream or butter container and bring it in for proper identification. If you find an insect over the weekend or cannot get into the Extension Office right away, place your insect in the storage container and put it in the freezer to preserve it until a professional can identify it.

At this point, Emerald Ash Borer has only been found in Omaha and Greenwood in Nebraska. The recommendation is to wait to treat for Emerald Ash Borer until it is found within 15 miles of the tree’s location. There are chemical treatments that are effective against EAB. Homeowners can use a soil application, but this is most effective on trees less than 15 inches in trunk diameter. If the tree is larger, professional tree care companies can use a trunk injection. Wait until the insect is found within 15 miles before any treatment is done because the injections wound the tree and we want to wait as long as we can before we begin wounding our trees. A homeowner should also decide if the tree is in good health and a good location before beginning treatments. Planting ash trees at this time is not recommended. If you will not be treating your tree, it might be a good idea to start a new tree nearby to replace the ash tree when the time comes.

At this time, the only thing we can do to help with the ever-expanding problem is to not move firewood or wood products.  Buy wood locally when camping and leave unburned firewood at the campsite when you leave. Also, determine if you have an ash tree in your landscape and watch the tree for signs of this beetle.

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 26, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for May 26, 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: Laurie Stepanek, Forest Health Specialist 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 bleeding heart plant that she wants to plant but the area she wants to plant it in is full sun all day. Will it be ok in that environment?

A. No, this is a shade plant. When plants that need part to full shade, such as bleeding hearts, are planted in full sun, the leaves will begin to burn as the summer goes on and it will not survive as long or produce as many flowers. The east side or the north side of a building is best for these plants where they may have morning sun but are protected from the afternoon sun.

boxwood with winter desiccation

Boxwood with winter desiccation, photo by Lindsey McKeever, Gage County Extension

2. A caller has some boxwoods that looked good in February but now have areas of dying leaves. What is this from and can it be fixed?

A. This is from winter desiccation. This winter was very dry and caused a great deal of damage to a lot of different evergreens and broadleaf evergreens. During the winter our evergreens are still transpiring. When we don’t get additional moisture naturally and the transpiration exceeds the moisture absorbed by the roots, the plants will show winter burn or winter kill. This can be pruned out and many plants will be just fine. However, if the damage takes the pruning into the part of the plant where leaves are absent, then it may be time to replace this particular shrub. Boxwoods are often damaged in Nebraska, so a Yew may be a better replacement.

3. This caller has a mailbox in full sun just off the street that is very hot for plants. Is there a type of groundcover that will survive and do better in this location than a rose moss has done in the past?

A. Sedum, Rose Moss, Dianthus, Rock rose, Cacti, Ice Plant, Basket of Gold, Wall Rock-cress, Hens and chicks, or Catmint could all be used in this area and will thrive. It may take a few of these plants to fill in, but they will be great after time.

4. A caller wanted to know what to do for transplanting and preparing a site for grapes?

A. Here is a good guide from Oregon State University on growing grapes. You can also find a lot of great information on grapes and other fruits from Connie Fisk on the Food.unl.edu website

5. A caller wants to know why his fruit bushes are not growing well? He is growing boysenberry, raspberry, and others that are planted in part shade on the East side of a building.

A. All of our small fruits would need to be planted in full sun. Try moving them to a location with at least 6-8 hours of sunlight per day, afternoon sun is best.

6. This caller has oak trees that have signs of 2,4-D drift. What can he do to help them? Will they survive?

A. These plants may drop their leaves and push new growth to help overcome the damage from the herbicide drift. There is not much you can do to help them through other than to keep the trees otherwise healthy. Ensure they are getting correct waterings and keep a mulch ring that is 2-3 inches deep. This damage may have also been from Dicamba, which is an active ingredient in Trimec and is causing many problems in our oak trees as well as many other tree species. Make sure when you apply pesticides you are reading and following the label, spray with low wind and cooler temperatures. Dicamba can turn into a gas and move to non-target plants in temperatures above 80 degrees. It can volatilize for up to 72 hours after application.

7. The cherries on a tree bloomed and were developing, now the cherries are brown and dead. What caused it? Can anything be done to fix the problem?

A. This could be due to a frost issue or due to brown rot. There is no way to fix it now that it has happened. If it is brown rot, you might try an Orchard Fruit Tree spray next spring to reduce the disease.

8. A caller has swamp white oak trees that leaves are curly on the old growth, but the new growth looks normal. What would cause this?

A. This is from a herbicide drift issue. The first flush of growth was affected by the herbicide damage but the new growth would be free from damage. Our trees will push secondary growth after being hit by pesticides and the new growth will be fine. There is nothing to do for it and the tree should be fine.

9. Do containers need new soil every year?

A. It is best to replace at least the top 4-6 inches of soil with new soil in containers each year to ensure there are enough nutrients to help the plants through the season. After one growing season, in a container, the plant will use up the majority of the nutrients in the soil.

10. A caller has a Japanese Maple that was growing in part shade, but many of the trees shading it were removed and now it is mostly in full sun. The bark on the south side is peeling and the branches on the south side are dying. Can it be saved?

A. This is a great deal of environmental stress to the tree that now cannot be changed. The tree has little chance of survival at this point.

11. Can herbicide drift come from granule products as well?

A. The granule drift comes from the wind blowing the actual granules, or the soil that is attached to the granules, to non-target plants and locations.

12. This caller has tomato plants growing in containers and the leaves, mostly the lower leaves, are turning brown. What can be done for this problem?

A. This is mostly due to the weather conditions we have had the past couple of weeks. Excessive rains and cloudy days have caused a slight fungus to affect the lower leaves. Pinch the damaged leaves off and ensure you water below the plant and it should recover with better environmental conditions.

13. A caller has the galls for Cedar-apple rust on his cedar trees and he also has apple and pear trees. What should he do to control this disease?

A. These are the galls that have the spores for the disease in them. In the spring, when we get rain, the galls open up and the spores are released to other trees nearby. This is a harmless problem on the cedar trees, but not to the apple and pear trees. If you have susceptible apple and pear trees where you have seen red to brown spots on the leaves in past years, you need to spray now with a fungicide spray.

This caller also has a silver maple tree with large holes that squirrels are living in. Can you control the squirrels so they don’t live in the tree?

A. There is no good way to control squirrels in the tree. Even if you trap for a couple, there are always more. The bigger concern in this situation is the decay happening in the tree. When large holes open in the tree, like this, there is decay happening in the tree. It would be best to have an arborist come in and inspect the tree to ensure it is safe.

14. This caller had 3 questions: Why are his vegetable plants already producing flowers and fruits when they are still very small? He planted peppers early and wants to fertilize them, what should he use for fertilizer? He is starting a bee-friendly prairie area that is being overrun by brome grass. What can he do to control the brome grass?

A. Many of our vegetable plants are stressed from recent rainy and cold environmental factors and are pushing flowers and even fruit on small plants. Snip or pinch off those flowers and fruits to allow the plants to push growth into the plant rather than into the production of fruits. Fertilizer can be applied as a side-dress to pepper plants now, but don’t fertilize with too heavy of Nitrogen and discontinue fertilization after this treatment. Too much nitrogen at the time when the plants should be producing fruits will cause them to produce more green, leafy material and not fruit production. Any general vegetable garden fertilizer will work. Brome grass can be controlled among broadleaf plants with grass-b-gon products to kill the grass but not the desired broadleaf plants.

15. A caller has 3 Austrian Pine trees that were spaded in 3 years ago. One isn’t growing as fast as the others and looks stunted in comparison. Should he replace the one smaller one by having a larger tree spaded in to improve uniformity?

A. The smaller tree may still pull through. However, if you have a new tree spaded in, you will have the same problem because spading a larger tree causes a lot of stress to the tree and it will take a few years for the tree to get through that stress period. So you will have the same problem with a new tree. If the smaller tree has good growth, leave it, it should get back into pace with the others.

16. This caller had some cedar trees removed a few years ago and is still having troubles getting new plants established in that area. How long will it be before he can get new plants to grow there?

A. There is no good estimate of this. The new plants are battling roots and compacted soils from years of the cedars being there. Add compost to the soil and mulch it for a year or two to help improve the soil.

17. The last caller of the day has a pin oak with yellow leaves. Why is this?

A. This is due to Iron Chlorosis, which is a deficiency of the nutrient Iron for the tree. This is very common in pin oaks in our area due to the high pH in our soils which holds on to the iron making it less available and harder for our plants to get. You can do trunk injections of iron, but that is only effective for 3-5 years each time. Iron granules are not very effective and we don’t recommend putting nails into the trunk of a tree due to the damage it causes. This is a young tree that will battle this problem its whole life. It might be time for removal and replacement with a different oak that doesn’t have so much trouble obtaining iron, such as red oaks.

Tree Galls

Spring is a great time of year. We can enjoy spending time outdoors with our friends and family and enjoy the views throughout our landscape. However, that view is sometimes interrupted by weird formations that show up on our tree leaves which are called galls. The good thing about galls is that they are not harmful to our trees, they are just displeasing to the eye.

Galls are commonly seen on many of our tree species. A gall is a deformation on the plant usually caused by an insect but they can be caused by fungi, bacteria, and other organisms. Galls can form on the leaves or on the branches but it is developed as a result of the feeding activity of the insect or mite that then lives inside the gall.

One of the most common types of galls is the Hackberry nipple gall which forms on the underside of the leaf of hackberry trees. This is a very common gall, in fact, it occurs so often that it can almost be used as an identification characteristic of the Hackberry tree. In the fall, the psyllids, or tiny black insects, come out of these galls to mate and often become a nuisance insect in our homes. They are so small that they can get through our window screens and enter our homes to fly around and pester our families.

HackberryNippleGall, S. Browning

Photo of Hackberry Nipple Gall by Sarah Browning, Lancaster County Extension

Another common gall that we are seeing right now is the bladder gall on Maples. This particular gall is caused by a mite. The signs we see from this insect feeding on our trees would be small, bright pink bumps on the top side of the leaves.

maple bladder gall

Photo of Maple Bladder Gall

Oaks also get a couple of galls. There is a leaf gall that is fairly common among oak trees called the oak apple gall which is a large, round, tan-colored gall on the leaves. It is a growth filled with a spongy center and contains one wasp larvae in the middle. Bur oaks commonly get a bullet gall which grows all over the branches of bur oak trees. These galls appear as marble-sized, tan, hard structures attached to the branches of the tree. The bullet gall, which is caused by a parasitic wasp, is generally not harmful to the tree, but if the infestation gets very high, it can cause branch dieback.

2016-04-01 10.52.50

Oak Bullet Gall

Cottonwoods get a petiole-leaf gall. This gall is caused by an aphid and is a puffy ball located at the base of the leaf where it meets the petiole, or the stem-like structure that attaches the leaf to the branch of the tree. The petiole-leaf gall will contain many small aphids later in the season that will not harm the tree.

These insect galls are generally not harmful to the tree. They mainly cause aesthetic damage and don’t affect the health or longevity of the tree. There is no way to control the gall insects once the galls appear on the tree and prevention is difficult and not recommended.

Part of the information for this article came from an article written by Mary Jane Frogge, a UNL Extension Associate from Lancaster County Extension.

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: May 12, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for May 12, 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: Dr. Paul Read, Viticulture Specialist from UNL

1. The first caller of the day called to ask when is the best time to take cuttings from grape vines and how should it be completed?

A: To take a cutting, when you cut off the dormant growth from the previous year, you can take those branches and put them in moist sand to get them to root. After the last spring frost of the year, you can plant those rooted branches outdoors. When you do this method, you need 2-3 buds on each branch. Put at least 1 bud into the ground and have 1-2 buds out of the ground for leaf growth. At this time of the year, you can complete the layering method of propagation. For layering, just bury a few of the longer branches that are still attached to the vine. Once they root, you can cut them from the main plant and replant somewhere else.

2. A caller has a 7 year old peach tree that is dropping leaves like it is fall. What would be causing this to happen and can it be corrected?

A: This could be abiotic stress due to unfavorable environmental conditions. It could also be from peach tree borer. Look along the trunk for small borer holes or sap oozing from branches or the trunk to know if it is the borer. If borers, spray the trunk with a fruit tree insecticide spray. If it doesn’t seem to be from insects, keep the tree healthy through a good mulch ring and regular watering as needed when natural rains are infrequent.

3. This caller has 2 concord grapes that were producing well last year but were taken by the birds before they could be harvested. How can you keep these birds away?

A: Bird netting over the plants to keep the birds out is the only good, effective method of managing birds in grapes.

This caller also wanted to know what is wrong with her peach trees? She has 2 peach trees that are 9-10 years old that now have an orange sap oozing from the trunk.

A: This would be from gummosis, a fungal disease common on peach trees. There is no real cure for this disease, it is just best to prune out the small branches that are affected and cut 6-8 inches below the infected area. Dip your pruners into a bleach/water solution between cuts to prevent further spread of the disease. It could also be from peach tree borers. In that case, use an insecticide labeled for use on peaches for borers.

4. A caller has a row of cottonwoods but there is one tree in the middle that always has yellow leaves rather than green leaves. What is wrong with it and can it be corrected?

A: This is most likely due to an iron deficiency in this tree. That can be corrected by having a certified arborist come in to do a trunk injection. The granules or stakes around the tree are not very effective. Often, iron chlorosis is a sign of other problems with the tree and may be the beginning of the end for the tree. That being said, many of our trees live many years after developing an iron deficiency and some just need an iron injection every 5+ years to live a long and happy life.

Tree hole for blog

Photo of the damage occurring to the Maple tree.

5. A caller has some maples that were recently pruned and the branches had a fungus and some white powdery substance in them when the branches were removed. What is wrong with them and do they need to be removed?

A: This caller emailed me with photos of the problem so I could see for sure what is wrong with the plants and if it can be corrected or if it is a safety issue. Unfortunately, this does look like decay in the tree. Decay within the interior of the tree can be dangerous for when it may fall, the tree is not stable when it has decay. I would guess that the tree has a large limb that was removed at one time and it was too big or improperly cut and now there is a large hole leading into the tree. I would get a certified arborist out to take a look and possibly remove the tree.

6. This caller has a cedar windbreak and would like to plant crabapples. Can crabapple trees grow near a cedar tree?

A: Yes, you can plant crabapple trees near cedars, just make sure that you select a variety that is resistant to cedar-apple rust to avoid having to spray annually to avoid the damage from cedar-apple rust.

7. A caller has a blue spruce tree that is 8 feet tall and was planted 14 years ago that died over the winter months. What happened and how can it be avoided in the other trees in the row?

A: This could be due to a canker which is a fungal disease that stops the flow of water and nutrients from the canker point outward and upward through the tree. If the canker occurred on the lower part of the trunk it would cause the tree to die. There is no cure for canker and no way to prevent it. It could also be due to a root issue that could have happened when the tree was planted or in the nursery. The tree may have a root that girdled the stem killing the tree or it may have been planted to deeply. When you remove the tree, look at the root system to see if this was the problem.

8. This caller has small brown circles in the lawn all around a tree. This problem occurs every year later in the summer in the same location of the lawn. What would be causing this and can it be controlled?

A: This is most likely due to summer patch, a common lawn fungal disease that occurs in the mid-late summer. Normally, this isn’t something that is treated for because it doesn’t occur in the same location every year, but for this caller, it does. Management practices in the lawn can help, such as mowing higher and doing core aeration to reduce the thatch layer in the lawn. If necessary, fungicides labeled for summer patch can be used from now until the end of June.

Summer Patch, L. Giesler turf update

Summer Patch in Kentucky bluegrass photo by Loren Giesler, UNL Plant Pathology

9. What is a better species selection than using Bradford pear?

A: Chanticleer or Cleveland Select are better options for pear trees than a Bradford Pear. Bradford pears tend to have narrow branch arrangement that leads to more broken branches from high winds and storms. These two options are better choices because their branches are wider when arranged on the trunk.

10. A caller has a maple tree that is half green and half a much lighter green color. What would cause this and can it be corrected?

A: The soil pH is higher on one side. A disturbance on the one side could cause it to have iron deficiency on the lighter green side. Try to spray chelated iron on the lighter green side to fix the problem.

11. When is the best time to start asparagus?

A: Spring is the best time, from March to April is prime time for planting asparagus crowns. Be sure to still wait 3 years before full harvest begins.

12. The final caller of the day had 2 questions. She had botrytis on her strawberries last year and sprayed a week ago. Does she need to spray again? Also, can an Annabel Hydrangea be planted in full sun?

A: For the strawberries, 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. Annabel Hydrangea is one that prefers partial shade. I would avoid planting it in full sun on the South or West side of a building where it would get too hot.

 

Peach Leaf Curl

Lately, I have had quite a few community members come into the office with a problem on their peach tree. The leaves look funny and have a pinkish color to them. The same problem is being seen throughout the area and unfortunately, there is nothing we can do about it, at least not for this year. The problem many people are dealing with is Peach Leaf Curl.

Peach leaf curl is caused by the fungus Taphrina deformans. This fungal disease is one of the most common diseases in the home orchard and can affect the blossoms, fruit, leaves, and shoots of peaches and nectarines. (Cherries have a similar leaf curl diseases caused by T. cerasi.) Peach leaf curl is more severe following cool, wet springs; temperatures between 50 and 70 degrees F are ideal for infection, which is why we are seeing it so often this year.

Peach Leaf Curl, Paul Bachi, Univ of Kentucky R and E Center, Bugwood

Photo of Peach Leaf Curl is from Paul Bachi, University of Kentucky Research and Education Center, Bugwood.org

The primary symptom is a thickened, puckered area on leaves which will turn yellow to red or purple with the loss of chlorophyll. These leaves may prematurely drop, weakening the tree and making it more susceptible to other diseases, pests, and cold injury. The disease can also result in reduced fruit set, size, and quality.

A single fungicide spray applied while trees are still dormant (just prior to bud swell), thoroughly covering all branches, shoots, and buds will control peach leaf curl. Effective controls include Bravo, Ziram, and copper compounds.

At this time of year, most infection has already occurred, and fungicide sprays are relatively ineffective. Fruit on defoliated trees should be thinned to reduce stress and improve tree survival.

This information on Peach Leaf Curl came from Connie Fisk, a fruit tree expert for Nebraska Extension located in Cass County. Read more from Connie on her blog, Food Adventures with Connie

Another thing to think about this time of year, is what type of fruit tree to plant if you are thinking about planting new trees. You need to decide what type of fruit you prefer to grow, what you will be using your fruit for, and if the tree is self-fruitful or if you need to plant a pollinator tree nearby. It is also best to plant fruit trees that are resistant to the common diseases found in our fruit trees. For apple trees, select a tree that is resistant to cedar-apple rust and apple scab. For peach trees, choose a tree that is resistant to bacterial spot. For pear trees, choose one that is resistant to Fire Blight.

apples-A. Henneman flickr

Flickr image courtesy of Alice Henneman per CC license

For Apple trees, some good choices include Redfree, Johnafree, or Liberty. For Pear varieties, look at Moonglow, Luscious, Lincoln, Magness, or Seckel. For Peaches, choose Reliance, Red Haven, Contender, or Madison.

There are many other great choices for fruit tree varieties to use. Nebraska Extension released a NebGuide in July of 2016 called ‘Fruit Tree Cultivars for Nebraska’. It is a good guide that helps you to find the fruit tree variety or varieties you need for your fruiting wishes.