Yard and Garden: June 15, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for June 15, 2018. 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 3, 2018. 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 UNL Extension

1.The first caller of the show wants to know how to attract more fireflies to his yard?

A. Fireflies like moist environments. So a location of higher shade that is kept moist with dense plantings will attract them to your landscape. Also, just keeping the lawn watered will help.

lonestar tick, lifestages, J. Kalisch

This photo from Jim Kalisch, UNL Entomology, shows the lifestages of the Lone star tick

2. This year has high populations of ticks found in nature. Many ticks around this area have been identified by Jim Kalisch as being the Lonestar tick. Is this species of tick increasing in population in Nebraska?

A. Lonestar tick nymphs are being found often now. They have been found in the southeast portion of Nebraska. The range for this tick has spread north over the past decade or 2 to include the southeast corner of Nebraska. Prior to this, the Lonestar tick was found further south of Nebraska. This tick is significant for health reasons because it spreads many diseases including Southern Tick Associated Rash Illness (STARI), rabbit fever and erlichiosis. It also can causes a food allergy to red meat. Because of this, it is always good to remember to use insect repellent sprays and check yourself for ticks when coming inside from outdoor activities.

3. A caller has a blue spruce that was planted from a container last spring at 3.5 feet tall. Now it is turning brown on top and the branches are getting a shepherd’s crook at the end of the branches. What is causing this and can the tree be saved?

A. This is likely a fungal disease called sirococcus shoot blight. The best time to spray the trees is in May with additional sprays every 3-4 weeks as rain occurs.  It is a little late for the spraying of this tree, but it would still be beneficial to spray the tree to reduce the spread. Using a liquid copper fungicide would be best. Next spring, spray the trees when the shoots are 1/2 to 2 inches in length.

Squash bug-NH-pic monkey4. An email question came through asking how to get rid of pumpkin bugs in the garden this year, he faces them every year?

A. From his description, these are likely squash bugs. They are common pests in pumpkins, as well as in cucumbers, squash, zucchini, and melons. If these bugs are in pumpkins that are for ornamental use only, not for consumption, a systemic insecticide called acetamiprid can be used. Be careful if using in a garden with other edible garden plants, read the label for the PHI to tell you how long to wait from when you apply this product until you can harvest again. If these plants will be used for consumption, eight or bifenthrin would work for less PHI. Still pay attention to the PHI for harvest times.

5. This caller has oriental poppies in her garden that have faded now. They are planted in an area that is becoming overtaken by weeds. She would like to plant mums around the poppies to get a longer season of interest. How can she work the soil to plant the mums and kill the weeds, while not harming the poppies.

A. Tilling through the garden space may not be the best answer. If you till through weeds, it can sometimes cause more of a problem. Many weeds will propagate vegetatively, so new plants will form from each of the cut pieces of the main plants. Also, it would be difficult to till around poppies safely. I would recommend carefully using glyphosate on the weeds for better control, do not use any 2,4-D or Dicamba products this time of year due to problems with these chemicals turning into gas and moving to non-target plants. Spot spraying the weeds or painting the chemical on the leaves would get more of a kill for the weeds and the glyphosate product will not turn into a gas and it deactivates as it hits the soil. Finally, just go in and just dig holes where the new mums will be planted.

6. A caller wants to know when the best time is to move tiger eye sumac?

A. Fall would be fine to move this sumac, such as in September.

This caller also has a 5-year-old peach tree that has borers. How can the borers be controlled?

A. For borer control, it is best to treat the base of the tree and the branch junctions with bifenthrin. This chemical will have to be reapplied a few times through the growing season to help with the lesser peach tree borer and the peach tree borer which emerge at different times of the year. Applications should be made in June and again in July and August for best control.

7. This caller has a 2-year-old black raspberry. The new growth is curling and turning black, it seems to be moving from the tip of the leaf inward. What would cause this?

A. This could be from a scorch issue. Make sure that the plants are getting enough water, but check before just watering more. Often when we get scorch we automatically go to overwatering which can also be quite detrimental to the plant. For more information on scorch and how to deal with it, visit the Gro Big Red Blog Post on Scorch from Kathleen Cue.

8. A caller emailed pictures of his fir trees that are having some issues. One, was planted about 6 years ago and the bottom few branches have turned brown. He watered through the winter but has not yet this spring. The other fir was replanted about 4 years ago and the top is green, but the bottom half is sparse. What can be done for these trees?

A. The bottom branches of this tree could be just dying from shade or from a needle drop issue. That branch or 2 can be removed and the tree should be fine. It would be best to water this tree. Put the sprinkler in the root zone of this tree weekly for an hour or so to help it. As for the smaller tree, it is not going to make it. The lower portion is quite bare and it will be very difficult for the tree to come back from that.

9. What do you do about sandburs in a lawn?

A. Crabgrass preemergent herbicides should be used earlier in the season to control sandburs before they grow. Sandburs are a summer annual weed just like crabgrass. For post-emergent control, quinclorac products will work best. If it is in a driveway or other non-plant area, roundup 365 might be fairly effective.

10. A caller has a birch tree that needs a large branch removed, when is the best time for this? They also have a pear tree that needs some pruning, when is the time to do this? And when can they prune a mock orange bush?

A. New research is showing the timing for pruning has changed from what was previously recommended. We now recommend pruning in the late spring to early summer, so that would be right now for both the birch and the pear tree. It is better to wait until a little later in the spring to prune birch trees to avoid problems with heavy sap flow. The concern with this is that it was stated that a large limb needed to be removed, which can be quite harmful to the tree. Don’t remove a limb that is more than 1/2 the diameter of the trunk and do not remove more than 1/4 of the tree in one growing season. Removing a large limb leaves a large wound that the tree is not able to seal up. If the wound doesn’t get sealed, then decay can begin to move through the tree which can lead to the death of the tree in many years. In addition, removing more than 1/4 of the canopy in one season will remove a great deal of the photosynthetic area from the tree, which can harm the growth and development of the tree. The mock orange bush should be pruned within a few weeks after blooming for the year because it is a spring blooming shrub.

11. The last caller of the day wanted to know about pruning tomatoes and how to do it?

A. Tomatoes can be pruned if desired, but it is not necessary. If desired, only prune on indeterminate tomatoes, avoid pruning determinate tomatoes. Determinate tomatoes already will only grow to a certain size and produce a certain amount of tomatoes so they do not need to be pruned. Pruning tomatoes can decrease the amount of tomatoes produced and increase the size of the tomatoes and it can help increase air flow to reduce diseases. It will also help keep your tomatoes off the ground. When the plants are young, remove some of the branches. In some locations, 2 or more leaves will start to develop from one node, remove all but one. For more information on pruning tomatoes, here is a guide from Minnesota Extension.

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Yard and Garden: April 28, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for April 28, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and 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: Dick Campbell, Owner of Campbell’s Nursery in Lincoln, NE

1. The first caller of the day has a Lilac that has bloomed in the past, but it isn’t blooming much. It has never been a reliable blooming shrub. What is wrong with it and how can it be fixed?

A: This plant was bloomed a few times in the fall, which would cut off the blooms for the following spring. However, this isn’t the only problem because for the past couple of years they have been better at timing their pruning. A late frost could have hit the blooms causing problems with bloom, it may reduce the overall bloom amount. Also, this could be a nutrient issue. A good fertilizer, such as bone meal, could be incorporated into the soil surrounding the plant to help with the nutrient availability.

2. A caller has ribbon grass that has died out in the center. This dead center has continued to get larger over the years. What can be done about that?

A: This plant needs to be divided. Many perennial grasses will develop a dead center when it is time to dig them up and divide them. The spring is a good time to do this for grasses. Iris plants will do this as well, they are best divided and replanted in the fall.

3. This caller has a weeping Norway spruce that is bending over heavily. Should it be trained to keep it more upright?

A: This is a typical growth habit for a weeping Norway spruce. They bend over more than some of the other weeping varieties. It would be good to put a small stake along the trunk of the tree to support it for more upright growth.

This caller also wanted to know what the timing was for spraying apple trees for Cedar-Apple Rust?

A: Now would be a good time. When the galls on the cedar rust have come out to look like a slimy glob in the spring rains it is time to spray. Those galls have just begun to open up and release the spores. For more information on cedar-apple rust, see this NebGuide.

Photo of Cedar Apple Rust Gall photo courtesy of Mike Lewinski via Flickr Creative Commons License

4. A caller has a cherry tree that has a split going up it and now it has sawdust around it on the ground.

A: Often we see insects in our plants as a secondary problem. What you are dealing with here, is most likely carpenter ants. They have come into the split in the tree and are making a nest in the rotting heartwood. The carpenter ants are not doing any more damage to the tree than what is already done. They can be killed by using an insecticide dust in the tree crack, such as sevin. However, the more concerning issue is the crack in the tree. If the tree is very large it may be a hazard. Tree removal may be necessary. If the crack is not very deep, it could be a frost crack which would be less hazardous.

5. Can you grow English Walnuts in Nebraska?

A: Yes, they can be grown here, it is most likely you will have to plant them from a seed as there aren’t many grown as plants for sale. Check with the Nebraska Nutgrowers Association for more information and seed/plant sources.

6. This caller has a blue spruce that is not growing well. It was planted 17 years ago and hasn’t grown more than a couple of feet in this time. What is wrong and can it be fixed?

A: The tree could be battling with too much brome grass growing around it and competing for nutrients and water. It would be beneficial to kill the brome grass and to add a mulch ring of 2-3 feet out and 2-3 inches deep around the tree to help reduce competition. This also could be a root issue that there would be no fix for. Often times, our trees are planted too deeply or grown in a container too long causing the roots to circle the tree. Once the tree is planted, there is no way to fix these conditions and the damage may not be present in the tree for 10-15 years after it was planted. This could be the case with this tree. Try adding mulch and ensuring proper irrigation through the growing season and it may come out of it.

7. A caller has a redbud that is 8 years old. The branches are dying and there are holes in the trunk. It seems that only one branch is still alive on the tree. What can be done for the tree? Or should it be removed?

A: The holes could be from borers that can be treated, but are often a secondary pest. If only one branch is left alive on the tree, it may be time to replant.

8. This caller is planting a new garden in an area that was a cornfield until this year. What do they need to do to the soil to plant in it?

A: Because this has been used as a crop field, I would advise a soil test to see where all the levels of pH, organic matter, Nitrogen, Phosphorus, and Potassium are at and to ensure vegetable crops will even grow in the soil that has been heavily planted for many years.

9. A caller is cleaning out dead and dying pine trees in a windbreak. Do the stumps need to be removed? What can be done to get it ready to replant?

A: If they are Junipers, or eastern red cedars, they can simply be cut off at ground level and they will not regrow. With some of our windbreak plants, they may need a stump treatment of 2,4-D or Roundup or a mix of the 2 products. If you are planning to plant a new windbreak where you removed these plants, it would be beneficial to grind out the stumps. If there is enough space, you can replant around the old stumps, just stay a few feet away from the stumps left behind if you don’t remove them.

10. What is the best care to give to seedling trees given to students for Arbor Day?

A: Grow the seedling in a pot for a year. When winter comes either plant the pot in the ground with heavy mulch or bring the container into the garage. Next spring, plant the seedling into the ground and protect it with fencing from rabbits and deer.

11. A caller wants to know how to control sandburs and where you can purchase milkweed plants?

A: Sandburs are controlled with crabgrass control products. As a preventer, using crabgrass pre-emergent herbicides will also prevent the germination of sandburs. If they have already germinated and are starting to come up, you can use a post-emergent herbicide for crabgrass such as quinclorac or Drive or Dimension. You should be able to find Milkweed plants at many local nurseries.

12. This caller has a white powdery substance on her peonies. What is it and what can be done for it? Also, she has a cherry tree that was severely damaged from deer, but now there are new suckers growing from the ground around it. Can those cherry tree suckers be grown into a new tree?

A: The white substance on the peonies would be powdery mildew. It is not very harmful to the plant. You can use a fungicide on it to control the spread of the disease. Also, make sure you cut off and remove the above ground growth that dies back in the fall to reduce the spores that overwinter for next year. The cherry suckers may not come up as the same species as you had planted and they may not be strong growing. Many of our fruit trees are grafted for a strong root system but desired traits from other trees. When suckers grow from the roots, you only get the type of tree that the main root system was and not the more desirable traits from the above ground portion of the plant. You can try it if you have room, but otherwise it would be best to start over from a new tree.

13. A caller put preen on his garden earlier this spring to stop the weeds. Now he is concerned if the plants he starts from seed this year will grow?

A: Unfortunately they will not grow where the preen is without extra care. You can either plant these plants from transplants or as seed in another location or in pots or you can till the bed to destroy the preen that is working as a barrier in the garden. Once you have gotten seeds to start growing in the garden, you can reapply the preen to reduce weeds later in the season.

14. A gentleman has holes around his house that are 1.5 inches in diameter and his tulip bulbs have been eaten off. What would cause these holes and how can the “critter” be managed?

A: This could be from either 13-lined ground squirrels or from voles. If it is voles, there would be runs in the lawn. Place a couple of snap-type mouse traps perpendicular to the runs in the lawn to manage the voles. If it is 13-lined ground squirrels, see this publication from UNL.

Yard and Garden: July 1, 2016

Yard & Garden for blog

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

9. What do you do for sandburs?

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

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

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

 

Japanese Beetle, 7-16 Acreage

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

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

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

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

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