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.

 

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.