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: March 24, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for March 24, 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: Cole Thompson, Assistant Professor of Integrated Turfgrass Management at UNL

1. The first question of the year was a caller who had 2 peach trees that were three years old when they died last year. He cut the trees off and now there is suckers coming up from the ground where those trees were. Will these trees grow and produce peaches?

A. These trees will grow and will most likely produce fruit. However, they will not be a strong growth and the peaches produced may not be the variety that he originally planted. Many of our fruit trees are grafted to a hardier rootstock. If they die back or produce suckers, that growth will be the type of tree that the roots are not the type that the scion, or top part of the graft union, was. Also, because it is from a sucker, it is not going to grow as strong and upright as the main tree. He can try to keep them going but it would be best to plant new trees as well, if he has the space for both, he can keep both the suckers and new trees. If he only had room for a couple of trees, I would suggest starting the trees over from new trees.

2015-06-25 10.19.56

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

2. This caller wanted to know what the difference is between Roundup and Roundup 365?

A. Roundup 365 contains a chemical called imazapic which gives the traditional glyphosate product more of a soil residual. The Roundup 365 is labeled only for use on and around hardscape areas such as patios, gravel paths, and driveways. The label claims that it lasts in the soil for up to 12 months, so it should not be used around trees, shrubs, or areas you plan to reseed. Regular Roundup can be used in an area around plants and where you plan to seed after the recommended wait time. You would need to be much more careful with the Roundup 365 because of the soil residual around other plants.

3. A caller has pussy willow branches that were brought indoors and placed in water to begin rooting. They have now developed roots. Can they be planted outdoors now?

A. Yes, as long as the roots have begun to form and the ground can be worked, it would be fine to plant them outdoors now.

4. When is the best time to reseed a Fescue lawn in Southeast Nebraska?

A. Fall is the best time to reseed a lawn, but it can also be done fairly effectively in the spring. It is harder in the spring due to the weeds that compete with the grass seedlings. If you plan to reseed in the spring, it is best to wait until late April to early May for that. If you seed earlier in April, increase the seeding rate to compensate for the loss due to the colder temperatures. When you seed, you can apply tenacity or a mesotrione product to the seedbed to help with weeds. Tenacity is safe for use at seeding. It is also a good idea to seed with a starter fertilizer to help get your seed started strong.

5. This caller has a birch that was cut down last fall. The remaining stump is oozing a lot of liquid right now. How do they kill the birch entirely to stop the liquid from oozing out of the stump.

A. Birch trees are one of the species of trees that tend to “Bleed” heavily in the spring if they are pruned. They have a high sap flow in the spring which will lead to the oozing of large amounts of sap through any open wounds. On a normal pruning cut to a tree with high sap flow, it is not harmful to the tree. This tree still has living roots and the wound from cutting it off is exposed so the sap still will flow through. This tree either needs to be treated with chemicals to kill it or the stump needs to be ground out to stop this sap flow and to be able to plant new plants in the area. You can drill new holes into the tree and apply 2,4-D to those holes to start to kill the tree. With chemicals, it will take a few years to fully kill the stump.

6. Can raspberries be transplanted now?

A. Yes, raspberries should be planted as early as the ground can be worked in the spring, so now would be fine. It is best if the soil was prepared last year by spraying all the weeds and incorporating organic matter. This will help to ensure you have a raspberry planting to last many years.

2016-11-22 16.59.14.jpg

7. A caller planted grass last fall and held the seed to the seedbed with a biodegradable plastic barrier designed for seeding turf. However, now the plastic is not breaking down and it is getting stuck in the lawnmower. Is there anything they can do to break it down quicker? It will disturb the lawn too much to try to pull it out now.

A. Pulling it out without disturbing the lawn would be the quickest, but if that is not safe to do without tearing up the lawn, that isn’t the best option. Try to water it down or hope for rain, the moisture may help to break it down faster than it sitting dry. This winter was quite dry which may have delayed the breaking down process.

8. This caller had a giant tree fall in his yard. He has removed most of the tree but about 5 feet of the trunk is still standing in the yard. What can he do with the stump?

A. It would be best to cut that trunk off at the ground level and grind the stump out so that you can replant either with turf or with a new tree. If you don’t want to grind it out now or replant, you can cut it down to the ground level and place soil over it to allow it to naturally break down under the soil.

9. A caller has been growing watermelons but they tend to wither and die early in the year. What is wrong and how can he improve his crop?

A. It sounds like this caller has squash vine borers that get into his vines in the summer months. Squash vine borer is a type of moth larvae that gets into the stem of the vines and blocks the movement of water and nutrients through the plant. They are very common in melons, squash, cucumbers, and pumpkins. To avoid the damage from this insect, use a spray or dust formulation of sevin or eight on the base of the plant regularly through the growing season starting in June. You can also use aluminum foil or a toilet paper tube around the base of the plant to act as a barrier between the plant and the female squash vine borer adult who is trying to lay her eggs on the plant.

10. This caller has 25 bur oak trees that were planted 4 feet apart with the idea that some would die to space them out further. Most did not die and are still planted too closely. Will they grow that close together or should some be removed?

A. Bur oaks grow quite large, but in a forested area they will grow fairly close together. They will grow this closely together, however it will shade out many of the branches and it will cause conditions that are conducive to diseases when trees don’t have the space to have good airflow. It would be best to remove some of the trees so that the trees left behind are given 20 feet or more between them. They are only 10-12 feet tall at this time so they would still be fine to be spaded out and transplanted to another location if you can find someone to spade them and someone to plant them somewhere else.

11. Is it too early to plant onions? Is it time to cut back mums that are left from last fall?

A. Late March to early April is the best time to plant onions. Wait to cut back perennials from last fall. The dead plant material will protect them from freezing temperatures for another week or two. The plant material can be removed in the beginning to the middle of April.

12. This caller has a yard with high dog traffic. What type of grass would be best to stay growing through the dog traffic?

A. High traffic lawns will decline. Increasing the fertility will improve growth in this area. Also, if you could limit the traffic patterns from time to time through the lawn, this would help as well. Kentucky Bluegrass will recover better in high traffic areas.

13. A caller has a bean field area that he is trying to turn back to a grass area. What type of grass would do good in this area for an non-irrigated recreational area on an acreage?

A. Buffalograss would be great for an acreage area. Once it becomes established it wouldn’t have to be irrigated much or mowed at all. It is a very low maintenance grass species that is native and you can choose many different newer varieties. UNL has good seed selections. Because this was a bean field it might be over-tilled so a roller may be necessary to firm the soil up before planting. Buffalograss is a warm season grass so it should be seeded May 1st.

14. The final caller of the day has an established cedar windbreak. Some of the trees were removed recently and there is a bare area in the nearby trees where they were shaded out from the removed trees. This area is only 7 feet from the house. What can be planted in place of these trees to help block the bare area in the windbreak?

A. Because this is so close to the house, don’t go with anything too big. A larger shrub may be a good choice such as a viburnum, serviceberry, some dogwoods or even some lilacs may help fill in. Some slender growing trees may also work, but full size trees may grow into the house.