Wild Cucumber

Windbreaks are very important to many acreage owners throughout Nebraska. A windbreak is used to block the wind, as the name implies. Winter winds can be very strong and a windbreak will help to reduce those winds, which will in turn reduce heating bills. Windbreaks can be built from a variety of trees and shrubs which are typically fairly tolerant of many problems. However, we do still see problems from bagworms, some fungal diseases, and weeds growing around the trees. A windbreak weed that is quite prevalent this year is wild cucumber or burcucumber.

About Wild Cucumber

Wild cucumber is an annual weed that grows up and over our windbreak trees. Due to all the rain we saw this spring, it is growing voraciously over our trees across the Nebraska countryside. It vines and has leaves similar to cucumber plants. The leaves are arranged alternately along the stem and have five triangular-shaped lobes on the leaves. The leaves are large, 4-10 cm long and 4-13 cm wide. If left on the trees long enough, a fruit will develop. The fruits of wild cucumber resemble a shorter, stouter cucumber with spines all around the outside. The plant climbs up onto our desired trees through the use of tendrils that twist around small branches to hold the plant up as it grows.

There is also a burcucumber plant which is closely related to wild cucumber. Burcucumber is also an annual weed that vines up and over windbreak trees. The leaves of burcucumber are more rounded and the lobes are not as deep as the lobes on the leaves of wild cucumber. Also, the fruits of burcucumber are much smaller and held in a groups. Wild cucumber and burcucumber are similar enough that management for both plants is the same and the names are often used interchangeably.

Managing Wild Cucumber

Wild cucumber is a plant with a shallow root system, so it pulls very easily. At this time of the year, this is really the only way to manage wild cucumber. Don’t spray 2,4-D or any other herbicide on the vines because anything that would control the wild cucumber can damage or even kill the trees that wild cucumber is vining up on. It would be best to pull it off and kill the plant before any fruits are produced to reduce the seedbed. However, at this time of the year they have already begun to produce fruits.

Since wild cucumber is an annual plant, it can be controlled with a pre-emergence herbicide in the spring. Products containing simazine will work to control this weed before it emerges next spring. Early May would be a great time to apply the chemical around the trees in your windbreak to make sure it is in the soil before the wild cucumber germinates. If you are having troubles with this weed this year due to the excess moisture, it would be beneficial to use the simazine next spring or you could have a similar or worse problem next year.

Yard and Garden: June 28, 2019

Yard & Garden blog, 2019

This is the Q&A for the Yard and Garden show for June 28, 2019. 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 2, 2019. 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: Dave Olson, Forest Health Specialist from the Nebraska Forest Service

1. The first question of the show was about a red twig dogwood that is overgrown. Can it be pruned now?

A. It would be better to wait until fall to prune it. It can be thinned by removing 1/3 of the canes at ground level. This type of pruning can be done every year to remove the oldest, least productive canes from the plant. You can also do a rejuvenation pruning on it by cutting the whole plant off 6-8 inches above ground level in the fall. This will help to bring back a deep red color in the stems that may have faded over the years. If you rejuvenate it this fall, it will not bloom next year, but should after that.

2. A caller has a couple of blue spruce trees with low hanging branches. Can those branches be removed now to make it easier to mow around?

A. Yes, you can remove those lower branches for mowing around. That can be done most anytime, but it is best in the late winter while the tree is still dormant.

3. This caller has green ash suckers that are growing up in her gooseberry bush. These have come from an ash tree that was removed a few years ago but is still suckering. What can be done to kill the ash seedlings and not harm the gooseberry bush?

A. It might help to get someone to grind out the ash stump to help fully kill the tree. If the stump is still there, the roots are likely still alive and doing what they can to bring the tree back, which includes suckering in other locations. Otherwise, you can just keep cutting the suckers off and eventually the roots will run out of energy. You could also cut back these suckers and paint the fresh cut with a roundup or glyphosate product.

4. A caller has gray bugs with long black antennae that are found in her garden. What are these and how can they be controlled?

A. These bugs could be blister beetles. They can sometimes come into our gardens. Certain years, they can be found in high population. If they are feeding on your garden plants, you can spray with some sevin or eight to control them.

She also wanted to know what would cause her iris leaves to turn yellow with brown spots in the yellow color?

A. This is likely from Iris Leaf Spot, a common fungal disease of Iris plants. This can be controlled fairly well by removing and destroying the infected plant material as it shows up. When watering, don’t water over the foliage which will spread the disease. If necessary, a fungicide such as Daconil can be used if sanitation isn’t enough.

5. This caller is trying to re-establish a new windbreak. For a quick windbreak solution, would the quick growing willow-type trees work well?

A. Willows and other very fast growing trees would not work as a windbreak, even temporarily. The fast growth in these trees would not be very strong growth and therefore it would break a lot in windy situations. It would be better to go with a larger shrub such as a viburnum or serviceberry to help fill in until the trees can grow up larger. These shrubs would block the winds quicker than some trees but withstand strong winds and storms much better than willows.

2015-07-30 16.59.34
Bindweed

6. What can be done to control bindweed in phlox?

A. Among other plants it is best to use the “glove of death” which is when you wear a chemical-resistant glove and then put a cloth glove over that. Then, dip a few fingers of the gloved hand into Glyphosate and rub those fingers along the stem and leaves of the bindweed to kill it. Basically, the idea is to keep it from flowering and producing more seed, hand pulling will help keep new seed from being deposited into the garden which can be viable for up to 60 years.

7. A caller wants to know if she can use the Extended control Preen on her petunias, they are not listed on the label?

A. If it is not listed on the label, you can’t use that pesticide on that plant. Stick with the general preen that has the petunias on the label to ensure correct application.

8. This caller has a pin oak tree with lower branches that are in the way of mowing. Can those be removed right now?

A. No, it is best to avoid pruning oak trees during the summer months. Oaks are susceptible to a disease called oak wilt that is spread by a beetle. The beetle is attracted to the trees after they have been pruned. Oak wilt can kill the tree if it is introduced to the tree. Wait until the fall or until the trees are dormant or early next spring before April to prune oak trees to avoid this disease.

9. A caller had her driveway lined with small mums that grew only to 1 foot tall. Over time some of them have been dying periodically throughout these lines. What could she switch to that is more winter hardy and stays at the 1 foot tall size?

A. That is a problem with some of our newer mum varieties, they just aren’t as winter hardy as they are advertised to be. The 1 foot tall size is difficult to find, I would suggest a groundcover to stay so small. Most other plants are going to be 2-3 feet tall at least. There would be some nice phlox that would look nice lining a driveway.

10. This caller has an oak tree that was pruned. The pruning is about 20 years old and has recently started oozing. What is wrong with it?

A. The tree could have borers or it could be a slime flux. It would be best to have a Certified Arborist look at the tree to determine what is causing the oozing and what can be done about it.

11. A caller has a mulberry tree with a flower bed underneath the tree. The high number of mulberries are now falling off the tree and rotting on the ground which is attracting flies. Is there anything that can be sprayed to treat for the flies but not harm the tree or the flowers growing underneath?

A. This is difficult since the fruit is already maturing and falling from the tree. If it was caught earlier, the fruits could have been quickly harvested by placing sheets underneath and shaking the branches. Once the fruits are on the sheets, they can be used or destroyed away from the tree if there are too many for consumption. Leaving the fruits to decay around the tree is attracting the flies. Using a sevin around the plants could help reduce the flies, but it won’t eliminate them entirely. Once the fruits have decayed completely, the flies should not be a problem.

2015-07-17 10.52.56
Rust on a Pear tree

12. This caller has an apple tree that gets rust even when they are spraying and then it moves onto their peach tree. What can be done for this disease?

A. Rust is found on apples, crabapples, and pears, but not on peaches. I would say there are 2 different problems. As for the rust, if the timing or chemical formulation is off a bit, the spraying will not work. Be sure to spray the trees with either copper fungicide or orchard fruit tree sprays. These sprays need to be applied every 10-14 days through the growing season starting at bud break, skipping the time frame while the trees are blooming to avoid harming pollinators. As for the peaches, it could be a fruit rot or other disease. The orchard fruit tree sprays will work on those as well, but it would be for a different disease on the peaches, not the rust.

13. A caller has a 6-7 year old apple tree that was girdled all the way around the tree this past winter by rabbits. It seems to still be growing fine, does the death just take a while after damage like this? Will it eventually die?

A. It could be ok, but most likely it won’t live through girdling all the way around the tree. If the damage was minor and the tree is able to seal up the wound, maybe it will be ok. I would say just to keep an eye on the tree and give it time to see if it gets better or worse. If the canopy isn’t full or has top dieback, you would want to remove it before it becomes a hazard.

14. This caller had large hail last week. It hit his vegetable garden. Is there anything he can do for the plants now? Will they survive and produce?

A. This depends on how badly the plants were injured and if the damage is mostly just on the leaves. It is a situation where time will tell, the damage may not be fully present for a while. There is nothing that can be done to fix this type of damage once it gets hailed on.

15. A caller has bare spots in the lawn due to shade under pine trees. What can be done about that?

A. Grass doesn’t grow in the shade. It would be best to use mulch under the trees or try to plant something else that thrives in shade conditions such as carex, sedge, or other groundcover or use shade perennial plants. Remember to plant the right plant in the right place for best growth.

16. This caller has rose with leaves that were eaten off of it. What would do that and how can it be managed?

A. This could be from rose slugs, but the damage sounds worse than what rose slugs do. It could be from Japanese Beetles. Those can be controlled with sevin, bifenthrin, or neem oil applied to the leaves. Be careful to avoid hitting the flowers with insecticide sprays to avoid injuring pollinators.

17. The last caller of the day wants to know how to renovate her strawberry plants?

A. According to John Porter, UNL Extension: She will want to manage weeds, but do nothing to disturb the plants. They should be left to grow until the end of the season. Tilling is okay around the beds, but in the beds hand pulling or minimal cultivation would be ideal to avoid damaging roots. Using a mulch like straw or woodchips can help control weeds in the bed. If the strawberries are a Junebearing variety, they are done producing for the year.  However, if they are a day neutral or everbearing variety they will have more production cycles throughout the season.

 

 

Yard and Garden: August 3, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for August 3, 2018. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am this was the final episode for 2018. It can be found again next spring on kutt995.com for online listening. If you enjoy reading my Q&A from the show each week, take my quick survey at: go.unl.edu/yardandgarden18 and be entered to win a free tree diagnostic book.

Guest Hosts: Kevin Christiansen, Horticulture Instructor at SCC Beatrice & Evan Alderman, Turfgrass Management and Horticulture Instructor at SCC Beatrice

1. The first caller of the day has a windbreak that has elms growing in it. How can he kill the elms and not harm the windbreak trees?

A. In this situation you need to use a herbicide that will kill the elms but will not be translocated through the roots into the surrounding windbreak trees. Tordon should NOT be used in this location. A good option would be either glyphosate, Roundup, or a 2,4-D product. Use these 2 products as a stump treatment on the tree just after cutting the tree off.

2. A caller has cucumbers that are blooming but are not producing any fruit yet. Why are the cucumber not producing? This caller also wondered how to control puncturevine?

A. The cucumbers could be due to no female flowers, if all the flowers are male, they will not produce any fruits. Sometimes our plants start with just male flowers and the females will come in later. It could also be due to low pollinators around the plants. If not many bees or beetles or other insects are found around the plants, they cannot be pollinated and may need to be hand pollinated. Hand pollination can be done by running a cotton swab through all of the blooms, this would move pollen from male flowers to female flowers. Puncturevine can be controlled with a 2,4-D product in the fall. Apply the 2,4-D in mid-September and in mid-October.

3. When should you transplant surprise lilies?

A. Surprise lillies can be transplanted or divided just after the flower dies back in the fall.

4. This caller has foxtail in the vegetable garden. Can anything be sprayed in the garden to control the foxtail?

A. There is nothing that can be sprayed over a garden to control foxtail and not harm the garden plants. The best option would be to use preen in the spring and summer to stop the germination of annual weeds such as foxtail. Be sure to use the preen that is labeled for use in a vegetable garden and wait until after all seeds planted have germinated. Mulch would help suppress the weeds in the garden as well. Grass clippings, straw, or other organic mulches will help keep the weeds down to help your vegetable plants grow better.

5. A caller was looking for assistance choosing fruit trees for his acreage. He also has rust on his fruit trees and wants to know how to manage it.

A. There is a great NebGuide on Fruit Tree Cultivars for Nebraska. For rust, this is not the correct time to treat for it. You can spray your trees in the spring with a liquid copper fungicide. For more on care and pest control of your fruit trees, visit: https://food.unl.edu/local-food-production

6. This caller has a windbreak of Red Cedars that are losing limbs. The trees are 100 years old and 30 feet tall. What is wrong with them?

A. This could be due to old age. It may be a good idea to start a new row of trees on the inside of the old row.

7. A caller has nutsedge in his lawn. What can he spray it with and can he still spray it?

A. Sedgehammer is the best control for nutsedge. It can still be sprayed now, however more control will be achieved if applied in the beginning of June, prior to the first day of summer. If sprayed before June 21st, nutlet production will be reduced, thereby reducing the population for the following year.

2014-10-06 15.27.18
Tree planting in the fall

8. This caller wants to know when the best time is to transplant an oak tree?

A. Fall or Spring are both good times to transplant a tree.

9. How do you control cattails and water lilies in a pond?

A. Rodeo is the glyphosate product that is labeled for use in water and it can be used on both of these weeds.

10. How can you control crabgrass and nutsedge in a lawn

A. Quinclorac can be used now for both of these weeds. Or use a pre-emergent herbicide in the spring and again in June for the crabgrass and sedgehammer for the nutsedge in June. Tenacity is another product that should work on both of these weeds.

11. A caller wants to know why we should worry about getting rid of cattails and water lilies in a pond?

A. Weeds in a pond can strangle the waterways or destroy habitat for fish. Some plant life along the edge of the pond can be beneficial, but too much can be a detriment.

12. This caller has lilies with caterpillars in the stem. What are those and how can they be destroyed?

A. This is likely a cutworm. Sevin or eight or Bt applied at the base of the plant can help kill these pests before they damage your plants.

13. When is the proper time to apply a winter fertilizer on a lawn?

A. Fall fertilizer can be applied in late August to mid September and the winter fertilizer can be applied in the middle to late October. It is no longer recommended to apply the winter fertilizer in November as previously recommended.

14. A walk-in listener has a weed they need identified and they need to know how to control it?

A. This is a weed called nimblewill. It is a warm-season grassy weed. It can be treated either with Roundup or Tenacity. If you use Roundup and reseed, apply the roundup now, while the nimblewill is still green and then overseed in a couple of weeks through the end of September.

15. This caller has spaghetti squash that was looking great and then one day it just died. What caused it to die and how can the other plants be protected?

A. This is likely due to squash vine borer. You can use sevin or eight to protect your plants from the squash vine borer. Be sure to apply it at the base of the plant where the plant comes out of the ground. These chemicals will need to be reapplied every 10-14 days throughout the growing season to protect the plants. Otherwise, you can wrap the base of the plant in aluminum foil to prevent the borer from getting into the plant.

16. A caller has watermelons with yellowing leaves. This has happened to his plants 3 years in a row now, he does rotate the crops in the garden. This damage starts at the base of the plants and will eventually kill the whole vine. He has mulch on the garden and waters slowly with a hose for 2 hours at a time. What is causing this problem? Also, when do you transplant iris?

A. This looks to be alternaria leaf spot. He is doing many things to prevent this disease already with mulch and his watering practices. It might be beneficial to try a liquid copper fungicide this year and next year as soon as the symptoms begin. Iris can be transplanted in the fall, September or October would be best.

17. A walk-in listener has a tree they want identified and they want to know why it keeps suckering and what they can do with the suckers?

A. This is a silver maple tree, they are prone to suckering. Suckers should be just cut off as they grow to reduce the amount of energy they take from the main tree. Do not treat the suckers with anything as that could injure or kill the main tree because the suckers are growing off the main tree roots.

18. This caller wants to know why their pepper plants are not growing well?

A.The peppers are planted too closely to a black walnut tree and will not grow well in that location. Black walnut trees produce juglone, which is basically a naturally produced weed killer. Certain plants are more sensitive to juglone, tomatoes and peppers are quite sensitive. The garden should be moved to at least 50 feet from the black walnut of the plants should be grown in a container or raised bed to avoid problems with the juglone.

19. The final caller of the year has hostas planted in a rock garden and they are not growing, they are still small like they were just planted there.

A. The rock garden may be too hot for the hostas and the rocks do not provide any nutrients back to the plants. It might be best to switch to a wood chip mulch to help reduce the heat and add some nutrients and organic matter to the soil.

2015-07-30 16.59.55
Bindweed

This caller also wanted to know what to do to kill the bindweed growing in her Iris beds?

A. Among other plants it is best to use the “glove of death” which is when you wear a chemical-resistant glove and then put a cloth glove over that. Then, dip a few fingers of the gloved hand into Glyphosate and rub those fingers along the stem and leaves of the bindweed to kill it. Basically, the idea is to keep it from flowering and producing more seed, hand pulling will help keep new seed from being deposited into the garden which can be viable for up to 60 years.

Yard and Garden: April 6, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for April 6, 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 Hosts: Jonathan Larson, Douglas/Sarpy County Extension Educator in Entomology and Jody Green, Lancaster County Extension Educator in Entomology

1.The first caller of the show has little blue flowers in her lawn. How can she get rid of them?

A. This is likely speedwell, it is a winter annual plant so it blooms very early in the spring then dies with warmer weather. At this point, since it is already blooming, just leave it as it will die soon and the seed is already set for next year. Spray it with a 2,4-D product late next fall after it has germinated or use a pre-emergent herbicide in the earlier fall before it germinates.

2. What is the correct mowing height?

A. 2.5-3.5 inches is the recommended mowing height for cool season turf in Nebraska. Too low will lead to more weed pressure and insect and disease issues because the turf cannot compete with these pests when it is too short. Make sure you mow enough to mow off only 1/3 of the turf blade each time you mow to avoid scalping the turf.

3. A caller asked if the treatments for Emerald Ash Borer (EAB) were killing the trees?

A. The most effective treatment methods for EAB are trunk injections, which can harm the tree. However, the tree can take about 10 treatments before stressing the tree to the point of death. If you are using Emamectin benzoate as the trunk injection chemical, the tree will only need to be treated every 2-3 years, giving it 20-30 years of injections before harm occurs. For the first few years of treatments, you may be able to use a soil drench rather than a trunk injection, again adding more time with your tree. A soil drench will work, but once the tree grows to 15-20 Diameter, the soil drench is not as effective. In the 20-30 years of treatments, you can get a very good start on a new tree nearby the ash tree to have a well-established tree growing in it’s place for when the ash tree needs to be removed.

Termites
Termites, Photo from the University of Nebraska Department of Entomology

4. Does wood mulch attract termites?

A. If the wood mulch is piled up so high to where the mulch is touching wood siding, it can be a pathway for the termites to enter the home. However, mulch is recommended to only be 2-3 inches deep and most concrete foundations will go higher than that. Also, if you have had termites in the past, you should be working with a pest control company for termite control and the chemicals will manage the termites from the mulch. You will not get termites from mulch, the mulch is cut up too small and termites will dry out in that condition, so that cannot happen.

5. This caller is replanting a windbreak. They have begun with an outside row of cedars and would like to know what to plant on the interior rows?

A. An interior row with multiple types of trees is best. Diversity will help your windbreak survive better if another disease or insect problem comes in to kill evergreen trees like pine wilt has. Good evergreen choices include blue spruce, black hills spruce, concolor fir, Douglas fir, ponderosa pine, white pine, and Norway spruce. You can even add in deciduous trees like oaks or maples to fill in as well.

6. A caller wants to know how to control poison hemlock on the edge of his field?

A. 2,4-D and Dicamba in a mix. This mixture is found in the product called Trimec as well as others. It is best to treat the poison hemlock while it is in the rosette stage, so early spring or fall. Do not allow cattle access to the dry matter after this has been sprayed.

7. This caller wants to know if fertilizer is needed to trees as they plant a new windbreak?

A. Fertilizer is not necessary for trees planted in Nebraska. Our soils typically have plenty of nutrients available for use by the trees. It wouldn’t hurt to add fertilizer at planting, but it isn’t necessary.

8. The final caller of the day wants to know how to plant a new asparagus patch?

A. Asparagus is a great plant for a home garden. Many people want to get plant starts from a neighbor to start their patch, but it is best to just purchase a new set of crowns. When planting asparagus crowns, dig a trench 8-12 inches deep and bury the crowns only under 2 inches of soil. As the plants poke up through the soil, add more soil until the soil is level. Avoid harvesting asparagus until the third season of growth to allow the crowns enough time for root production. For weed control, mulch is best, such as wood chips or grass clippings. Preen that is labeled for use around asparagus can be used in the spring to prevent annual weeds from germinating. In late May to early June, when finished harvesting asparagus for the year, you can break all the spears off below ground, leaving no green growth above ground, and spray glyphosate or Roundup over the bed to reduce weeds. After this, allow the plants to grow back up and produce ferns which will produce seed and help your patch grow. You can cut it back in the fall or in the spring before new growth begins.

Windbreaks

OLYMPUS DIGITAL CAMERA
Photo by Jan Hygnstrom, UNL Department of Agronomy & Horticulture

In the winter months you might begin to realize that your existing windbreak is not as efficient as it once was. This would be a good time to assess whether you need to replace some of these trees and start to think about planting new trees in the spring. Or maybe you just moved to a new home or are building a new home and this winter will help you assess the need for a windbreak at your new build.

A windbreak can be used for many different reasons. Obviously, the main purpose is to block wind, but it can provide many other benefits. Windbreaks can help protect a homestead from wind and snow, protect cattle from winter winds, reduce soil erosion on fields, provide food and habitat for wildlife and birds, reduce sound from busy highways to a home, and they can be planted for beautification of the landscape. The size and design of a windbreak depends on the purpose of the windbreak.

Most windbreaks should be at least two rows deep, but the number of rows depends on the purpose of the windbreak. For most acreages our windbreaks are only two rows, but they should be four to ten rows. According to the Nebraska Forest Service, a standard multiple-row windbreak should have windward rows of dense conifer trees or shrubs, interior rows of tall broadleaf trees and leeward rows of shrubs or conifers. The windward side is toward the wind, or on the outside of the windbreak and the leeward side would be on the inside of the windbreak.

Diversify the plant material in a windbreak. Many people are having to replace rows or entire windbreaks from where Pine Wilt came through and killed the scotch or Austrian pines in their windbreak. It is always best to use multiple species from multiple plant families within a windbreak so that you don’t lose the entire windbreak if something else comes in to kill a certain species of trees. Windbreaks don’t have to be made entirely out of conifers, shrubs and deciduous trees can be used in a windbreak to help increase diversity, help block wind, and increase food and habitat for wildlife. If using multiple types of plants and multiple rows, the typical windbreak should consist of a dense shrub in row one of the windward side, followed by two rows of dense conifers, two rows of tall broadleaves or conifers, and finally a dense shrub on the leeward side.

windbreak-design-nfs
Photo of a typical windbreak profile is from Windbreak Design NebGuide, Authors: Jon S. Wilson & Scott J. Josiah Extension Foresters with the Nebraska Forest Service.

Spacing is important to remember when planting your trees. The spacing requirements have changed quite a bit over time because many of the old windbreaks were planted too close together causing disease and shade issues to the plants. Plant your trees at least to the minimum requirements for within the row and between the rows.

  • Deciduous shrubs:4-6 feet between plants in a row and 15-20 feet between rows
  • Deciduous trees: 12-20 feet between trees in a row and 20-30 feet between rows
  • Conifer trees: 14-20 feet between trees in a row and 20-30 feet between rows

Now is a good time to begin thinking about your tree needs for your windbreak because the local NRD is selling trees from now until March 1. This is a good way to start a windbreak because you can get a large quantity of trees for a low cost. These trees will start small and are suited for Nebraska environmental conditions. They have a good selection of tree and shrub choices for your windbreak, but you do have to order in a quantity of 25. The local NRD’s vary in tree and shrub species available, but they have a good choice of many different species that will do well in Nebraska.

Yard and Garden: May 20, 2016

Yard & Garden for blog

This is the Q&A for the Yard and Garden show for May 20, 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: Natalia Bjorklund, Dodge County Extension Educator

1. The first caller of the day has a problem getting grass to grow where he removed an asparagus patch. What can he do to get his grass to grow?

A. This is a situation where it could be a few things attributing to the problem. He was keeping the seedbed watered, by watering it 3 times a day for about 10 minutes each time he watered. Watering is important for seedlings, they need to be kept moist, so short, frequent waterings are necessary. This area could be compacted from years of asparagus growth, so it might be beneficial to till the area up prior to planting. The other issue he is facing this year is that it has been quite cool this spring. Mixing the cool temperatures with the moisture, it might be too cold for germination. It is suggested to try again with new seed after tilling the soil up and a soil test may be necessary after that to ensure the soil is ok after so many years with asparagus on it.

2. A caller has a newly planted red maple tree with holes in the leaves. They do have black spots on the leaves as well. The new growth seems to not be affected like the original leaves. What would be the problem? Is this an insect issue?

A. This could be a leaf spot fungus with black spots on the leaves that have died out. When a leaf spot occurs on tree leaves, often the dead area will fall out of the leaf. Leaf spots are not very damaging to our plants. Since the new growth seems ok, it shouldn’t be treated and the tree will grow out of it and be fine.

3. A gentleman has evergreen trees that have brown tips on the branches. Is this being seen in other locations?

A. This is probably just an environmental problem on the branches that should fade in time. It is being seen in other trees, especially in white pines which are facing problems with winterkill, a common issue where the tips of needles on white pines turn brown after strong winter winds. It is not a concerning issue.

4. This caller wants to know how to control weeds growing around her containers that she is growing tomatoes and strawberries in? Can any chemicals be used that close to these crops?

A. Tomato plants are especially sensitive to chemical drift especially from 2,4-D which is a common herbicide used for lawn weeds. To be safest and not have problems from the 2,4-D being that close to the tomatoes and strawberries, mechanical control would be the safest option. mulching around the containers will help to keep the weeds from coming back.

5. A caller has blackberry leaves that are turning orange and then back to green. What would be causing this?

A. This sounds like the plant is having an issue with rust. The rust covered leaves then are falling off and new, uninfected leaves, are reappearing. Remove all infected leaves as soon as you notice the fungal spores. Rust will not kill the plant, it may show up on the berries slightly. Chemical controls are not necessary for a home gardener.

6. A gentleman planted fescue grass seed this spring and it seems to be a thin stand. Should it be overseeded? Will it fill in?

A. Fescue does not tiller out like bluegrass does. So it should be overseeded to help fill in the gaps in the turf.

7. What chemical can you use for tree stumps to help keep them from growing back?

A. 2,4-D is a good option to apply to a newly cut stump or drill into the stump and pour it into the holes. It can be mixed with Roundup to help as well. Do not use Tordon in a landscape setting as this would be a direct violation of the law.

8. This caller transplanted peonies a few years ago and they haven’t bloomed since they were moved. What is wrong with them?

A. If peonies are planted or transplanted too deeply in the soil they will not bloom. Dig the plants up and reposition them higher in the soil profile. It can be done now or in the fall, the fall would be the preferred time of the year.

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.

9. An email listener wanted to know if fertilizer changes composition over time?

A. Yes, it can break down and become less effective. If fertilizers are stored where they freeze and thaw continually or get moisture into them, they will not work as well as they originally did.

10. A caller has a windbreak that is dying. What are some good tree choices to replace the windbreak with?

A. Cedars, black hills spruce, Colorado blue spruce, Douglas fir, concolor fir, white pine, ponderosa pine, or Jack pine would all be good replacements. Make your windbreak out of a diverse selection of these trees. Don’t go with a windbreak of one tree species.

11. This caller has a peace lily that the leaves turn brown and then die back. It continues to go through this process. It has been repotted but is still exhibiting the damage. What is it and how can it be improved?

A. This could be due to overfertilization or too much salt content in the water. Try using distilled water for a while. It will flush out the salt content from previous water over time. Eliminate the use of any fertilization. It is a common problem in peace lily plants and they should be fine.

12. What chemicals can be used for bagworms and when should they be sprayed?

A. Bagworms are typically active in the third week of June and this would be the best time for spraying. The emergence of the bagworms is weather dependent and it can range from the middle of May to late July. Average years it is the third week of June for the timing of sprays. It is best to just watch your tree and spray when the new bags are 1/2-1 inch in length. You can treat them with general insecticides such as Sevin, Eight, Bt, or Tempo.

fern leaf peony, Lee Ruk Flickr
Photo of fern leaf peony from Lee Ruk via Flickr Creative Commons License

13. The last caller of the day wants to find a fern leaf peony. It seems to be hard to find. Where could she find this plant to purchase?

A. It should be fairly easy to find at a local nursery. Many of the box stores probably will not have this unique and interesting plant.

Yard and Garden: May 6, 2016

Yard & Garden for blog

This is the Q&A for the Yard and Garden show for May 6, 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: Jennifer Morris, Forest Health Specialist for the Nebraska Forest Service

1. The first caller of the day has peach, plum, and apple trees that were recently planted. Should she use tree spikes for fertilizer for the trees and when should that be done?

A. Fertilizer for a tree is usually not necessary in Nebraska soils. Let nature take its course to naturally fertilize the tree. Fertilizer should only be used on trees, or any plant, as it is necessary. A plant can be damaged or even killed if they have too much of a particular nutrient, so it is best to do a soil test prior to applying any type of fertilizer to your plant.

2. A caller has grasshoppers in his lawn and has problems with large populations in the past, but he also has beehives nearby where he would want to spray to control the grasshoppers. Can he treat the grasshoppers and not harm the bees?

A. Insecticides that are commonly used as sprays for grasshopper control are very toxic to bees. You should only use insecticides for the grasshoppers in this situation for serious situations where chemical control is necessary. If sprays are warranted, you would want to do so on a calm day so the spray does not drift to the bees and mow the lawn first to reduce flower heads present that could get pesticides on them to get onto the foraging bees.

3. There is a caller who wants to plant some new apple trees. The trees he currently has continue to face problems with cedar-apple rust. What tree cultivars should he choose that will not have the problems with this disease?

A. There are many apple trees that are resistant to cedar-apple rust. When planting a new apple tree it is best to go in with a tree that is resistant to this disease because cedar trees are common in Nebraska, which is the alternate host. This allows most any apple or crabapple tree to be vulnerable to the disease. For resistant cultivars, see page 3 of this NebGuide on Cedar-apple rust by Amy Timmerman.

4. A caller wanted to know if they can use Roundup (or other glyphosate product) in their garden to kill pampas grass? Can it be wiped onto the stalks of the plant and not harm the peonies or raspberries that are growing with the pampas grass?

A. Yes, it can be used among raspberries and peonies, but it needs to be carefully applied so that you don’t get it on the leaves or other plant parts of the desirable plants. Painting the glyphosate product onto the leaves of the pampas grass will work into killing the grass and will keep it from getting onto the desirable plants. Grass-b-gone may work for it in the peonies and can be sprayed directly over the peonies and cause no harm to them, however this product should not be used in crops that are used for food or feed.

5. A caller has a mum growing on the east side of their house and it didn’t come back. Why is that?

A. Some of our mums are not as hardy as others. This may have been one of the lesser hardy mum plants. This mum was also moved in the fall so it may not have been ready for the winter after being moved or it could be planted in a more exposed location. If there is no green showing in the plant at this point, I would assume it is dead and it is time to replant.

6. A walk-in clientele asked what the orange pods were on her cedar tree? She also wanted to know if she should remove the cedar tree or if she can treat it?

A. This is the gall of the cedar-apple rust disease. In the rainy portion of the spring these show up to release the spores of the disease to move to apple trees. This disease is not harmful to the cedar tree so no treatment and definitely no removal of the tree is necessary.

7. A caller wanted to know how to start a new plant from the family tree peony plant.

A. Prune off a branch of the peony and place it into rooting hormone and then into soil or into a pot of gravel that is kept moist to start roots. Once roots have begun, the plant can be planted into the ground.

8. This caller has a 12-15 year old apple tree that has bark on the trunk that is splitting on the southwest side of the trunk. What would cause this and is it harmful to the tree? He also has a tree that has holes in the trunk that are in a row and about the size of a pencil. What is this from?

A. The holes in a line on the trunk of a tree would be from a yellow-bellied sapsucker, a type of woodpecker. This is not harmful to the tree and has no management strategy. As for the bark splitting on the apple tree, this sounds like sunscald. This is a disease that occurs in the winter when the cells in the bark freeze and thaw quickly and bursts the cells causing the split. There is no control for this and the trees will typically live a long, happy life after this occurs but the scar will remain for the life of the tree.

9. The final caller of the day has a windbreak with evergreens that were planted 9 years ago and they are too close together. What is the recommended spacing for trees in a windbreak?

A. 14-16 feet between trees is the average spacing requirement at this point. You need to maintain that distance so that when the trees are full sized they don’t overlap each other too much which can cause more disease problems.