ProHort Update for October 2025

1. The Effects of Wind on Trees 

Nebraska can have very strong winds quite often. The wind really moves our plants, sometimes that movement is beneficial, but it can also be harmful to trees and other plants. 

Harmful effects of wind

Wind can be harmful to trees causing damage or even death. In very heavy storms, it can cause branches to break or even snap young trees off. When this happens, it is best to go in and correctly prune out damaged branches where you can. If the tree snapped off, remove what is left and replace that tree. 

In other cases, trees may just develop a lean or bend from a windy location. It can cause a flag form to develop in the tree, where the tree develops most of its branching on the leeward side of the tree so that it looks like a flag. This development is Mother Nature’s technique to avoid damage on the windward side for trees under constant high winds. These trees are often seen along highways where the winds are strongest and trees are unprotected. If a tree is uprooted, has trunk failure or more than 50% of the branches are broken, the tree should be removed. 

Drying out is another issue in the wind, especially from strong winter winds. Evergreens still transpire during the winter, which means that they are still losing moisture from their needles. If they don’t receive irrigation or rainfall that exceeds the amount they transpire, they can develop winter desiccation which develops as yellow or brown needles. They will develop new needles in the spring that will cover up the damage, but it will take a while to fill in. Be sure to irrigate trees through the winter and use antidesiccants on evergreen trees to protect them from this drying out. 

Dealing with Wind

Preventative actions can be done to trees to reduce the amount of damage in wind storms in the future. This includes: correct pruning, removal of dead, damaged or diseased branches, selection of trees with dense wood and strong branch angles, planting healthy trees with a good root system and plant them correctly including staking properly. Don’t forget to maintain overall tree health with proper mulching and irrigation. 

If damage does occur to your clients trees, make corrective pruning cuts, remove trees that have been uprooted, maintain adequate moisture around the trees, mulch around all trees with 2-3 inches of organic mulches, avoid fertilization until the plant recovers, and allow leaves and blooms to fall off the plant naturally while being patient as the tree recovers. 

Benefits of Wind

Even though wind can harm trees, some wind can help trees develop. When they are hit by wind they can develop better anchor roots. This is why you should allow your trees to move a little from side to side when they are first planted. Even if you stake the tree, it should be a loose staking that allows the tree to move which tells the tree to develop stronger roots to hold it in place. Once a tree has survived damage from storms, including wind, it will become more adapted for the next time a storm comes through and have less problems with wind damage. 

A great benefit from wind to plants is how it supports tree pollination and seed dispersal. Some plants are only pollinated through wind, so it is important to have some wind from time to time. Even trees pollinated by pollinators will benefit from wind assistance to move pollen. The wind also helps to move the pollinated seeds around to push them to grow in new locations. 

Trees suited for Wind

Certain tree species are more adaptable to stronger winds and don’t dry out as quickly as others, such as eastern red cedar or ponderosa pine. This is why I suggest avoiding the use of trees like white pines on the outside edge of a windbreak because they are prone to winter desiccation or dry out quickly in winter winds.

Planting trees and shrubs can help to slow down wind and reduce damage to other plants in the landscape. Trees are adaptable to wind damage. Those that are exposed to wind will grow stouter and will develop shorter needles or smaller leaves with shorter branches to deal with constant wind exposure. 

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2. September 30th growing degree days (GDD)

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4. What's Wrong with my Boxwood? Boxwood Threats and Other Pests, Michigan State University

Boxwoods make a nice addition to many landscapes. They provide green year-round, as long as they stay healthy. Many boxwoods are dealing with a lot of different maladies that can cause them to turn brown or even die. If your clientele are dealing with boxwoods looking less than ideal, they may have an insect pest, disease, or just environmental stress. 

Read this article for more information on many of the common boxwood pests and other threats from Michigan State University. 

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5. Conscientious Fall Cleanup

Plenty of folks out there are fine with a good mess, but most people, especially in the clientele realm, prefer something a little bit tidier. This often clashes with ‘best practices’ when it comes to maintaining a habitat that supports multiple forms of life like pollinators, beneficial bugs, birds, etc. Multiple species of native bees are solitary cavity nesters in search of hollow stems to crawl down into and construct their egg cells. From chrysalises to adult beetles, leaf litter or just general plant material on the ground gives winter protection to all manner of organisms that are aiding soil health, predating pest insects or providing pollination services. Seed heads of things like grasses, coneflowers and others provide important food sources for birds throughout the winter.

Unfortunately, most people prefer a ground-level cut so they don’t have to see any of the ugly black and brown died-back plant material hanging out, flopping over and just generally creating a non-uniform look in general. So what can we do to bridge the gap?

A lot of it may just have to do with having a conversation with customers and asking what they might be willing to tolerate or even just try out for a season. Honestly, some of the best winter views come from seed heads sticking out of snow and a bird perched on top. At a minimum, it is best to leave some kind of scattered leaves or plant material on the ground for the reasons listed above. There are ways to make it look more like mulch than mess. The next step is asking customers if they would be willing to leave at least a foot of stem on plants. This actually has potential benefits for both insects and the plants. Stems left on the plant will, over the winter and into the next season, hollow out to become nesting locations for some native bees. As they continue to age they will simply break off and either add to the mulch/soil matrix or are easily removed. Another aspect for the benefit of the plant is that the crown stays protected. A bare crown exposed to snow and other moisture and freeze/thaw events during the winter has a higher likelihood of rotting or heaving out of the ground – both of which only serve to cost more in the end by having to replace it.

We understand that most people prefer the look of clean mulch separating their plants, but as we learn more about how all the different parts of an ecosystem function for the health of our plants, soils and landscapes, it’s worth trying to have a conversation to educate clients who may be hesitant about the broad benefits to testing out some new practices.

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6. Too Late to Seed?

Even for the eastern part of Nebraska, the answer is probably “yes”. Fortunately, sodding is still a good option for regrassing, especially for small areas. Be sure to loosen the soil thoroughly beforehand, enrich it with quality compost and keep it moist, not soggy or dry after installation.  

More information on Establishing Lawns from Sod

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7. Fall Armyworm

Nebraska Extension has recently had many reports of fall armyworm in Southeast Nebraska, including high numbers of egg masses, caterpillars, moths and damage to turfgrass. Homeowners and landscape professionals are advised to scout for armyworm. There is no specific type of grass the larvae prefer. Masses of eggs or small caterpillars can be scraped off surfaces. Small caterpillars can be treated, but there is no need to apply insecticides unless identification is confirmed and there are large quantities.

It's important to realize that caterpillars are now more mature and insecticides won't be very effective. They are best controlled with pesticides when the caterpillars are 3/4 inches in length or less. Also, remember that these caterpillars will die when it gets cold this month. For areas with extensive damage, make plans to re-seed or re-sod these lawns. 

More information on Fall Armyworms 

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8. Controlling Broadleaf and Winter Annual Weeds

Early October is a great time to control broadleaf weeds in your customer’s lawns such as false strawberry, plantain, white clover and dandelion. Be sure to rotate the active ingredients between applications to prevent herbicide resistance. If the client has a history of winter annuals such as shepherd’s purse, henbit and speedwell, now is a good time to apply a preemergence herbicide for them as well. As always read and follow all label instructions, not only for effectiveness, but for the safety of yourselves, the client, their pets/kids and visitors to the property. 

Cool Season Lawn Calendar for Eastern Nebraska

Cool Season Lawn Calendar for Western Nebraska

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9. Watch out for Spotted Lanternfly

Spotted Lanternfly is not here yet, but we expect it to be here soon. Just be aware and ready for questions from your customers.  

More information on Spotted Lanternfly

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10. Commercial/Non-commercial pesticide applicators

If you have a pesticide applicators license which expired in April 2025 or you need to get a new license, testing options are listed below.

Testing-only Options

• Closed-book exams are given by the Nebraska Department of Agriculture (NDA). Preregistration is not required and there is no cost. Visit the link below for a list of available test-only dates, times and locations - https://pested.unl.edu/.
• NDA computer-based testing is provided through the Pearson-Vue company. Click here for a list of testing sites, categories available, dates, and registration information. Cost $55 per exam. (For applicators with multiple categories on their license, each category is charged the full testing fee.)

2025 Commercial/non-commercial training was held from January through April. Training schedules are available at https://pested.unl.edu/. Help your employees be successful at getting a license by purchasing study materials. 

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11. Digital Diagnostic Network - Need help with diagnostics?

Do you or your clients have questions you need help answering? Maybe you are a lawn care person and they're asking about trees, shrubs, or flowers? While you can refer them to their local Extension office, another option is Digital Diagnostic Network. Homeowners, lawn care professionals, pest control operators and others are invited to submit questions and photos through this website or with the assistance from an Extension professional at any Nebraska Extension office. All offices are equipped with high-resolution digital image capturing technology. Whether the question is about a lawn weed, insects on a plant, diseases in a shrub border or other, an expert panel of Extension professionals will review and respond to the question. To get started, create an account so the question can be reviewed and responded to via email. For more information and to create an account, go to Digital Diagnostic Network.

Bugging Out With Your Camera Phone - Tips on how to get a good picture.

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Reference to commercial products or trade names is made with the understanding that no discrimination is intended and no endorsement by Nebraska Extension is implied. Use of commercial and trade names does not imply approval or constitute endorsement by Nebraskas Extension. Nor does it imply discrimination against other similar products.