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Tag: trees

Historic Dry Spells Lead to Tree Stress: Help Ensure Your Trees Are Healthy Enough to Handle It

By Jason Griffin, Professor, Extension Specialist

Extension personnel across the state have been answering questions about dying/dead trees and shrubs since early spring. Symptoms have ranged from dead, to partially dead, to unusual growth, and late leaf emergence. While it is always good to scout for damaging insects (bagworms anyone?), disease pathogens, and physical injuries such as repeated mower damage to the trunk or recent construction projects that compromised root systems, this year we can blame a lot on our old friend mother nature. Since late summer 2022 through May 2023 rainfall has been scarce, a hard freeze came early, and summer heat exposed any weak landscape plants.

The National Weather Service office in Wichita (@NWSWichita) describes the
period from July 1, 2022 to April 23, 2023 as the 5th driest in history and the driest since 1989. Under those conditions, trees fail to accumulate adequate carbohydrates for the approaching winter, making them more susceptible to winter injury.

As drought continues through winter and spring, trees lack adequate moisture required for new spring growth. The result is trees failing to leaf out in the spring or pushing new spring growth that looks abnormal. If the plants were compromised by pests or physical injuries, environmental stress effects are magnified.

Trees do have mechanisms to deal with elevated temperatures. Unfortunately for the plants, heat rarely occurs as a single isolated event, and it is impossible to talk about heat without mentioning its partners in crime. As seasonal temperatures rise, precipitation becomes less frequent (or absent). Additionally, the Kansas wind machine gets fired up and cloud cover becomes less abundant.  This quadruple whammy reduces a plant’s ability to tolerate elevated temperatures. Trees and shrubs use transpiration to cool themselves. When soil moisture is lacking, transpiration is reduced, thereby exacerbating the issue. If the situation does not improve, long-term damage can occur. What we see now are the effects of months of drought, a cold winter, and summer heat.

Of course, most plants made it into 2023 with little noticeable difficulties, attesting to their resiliency. What can be done to reduce the stressors that lead to tree decline?

It is time to…..WATER, WATER, WATER!

By Brooke Garcia

The temperatures are reaching summer high’s this week, and it is more important than ever to be monitoring and increasing watering schedules. Adjusting irrigation settings to accomodate for extreme temperatures will be vital for the health and survival of new plantings, as well as established plantings.

Featured in the Horticulture e-Newsletter, Ward Upham discussed the importance of watering for trees and shurbs. The article is featured in the link here.

Here are some other timely blog posts about watering as well:

10 Rules for Planting Trees This Spring

By Brooke Garcia

This article was originally posted on March 18, 2021 on K-State Research and Extension News. For original article, please visit: Ten rules for planting trees this spring

Ten rules for planting trees this spring 

K-State horticulture expert shares tips to set you up for success

MANHATTAN, Kan. – If you’re planning to plant a tree in your yard this spring, there are some steps you can take to make sure your new landscape has its best chance of success.

Kansas State University horticulture expert Ward Upham shares the following ten rules for planting trees:

  1. Select the right tree for the site. To avoid serious problems, choose trees that are adapted to your location. Consider whether the tree produces nuisance fruit or if there are disease-resistant varieties available. For example, there are a number of crabapple varieties that are resistant to apple scab and rust diseases. Also consider the mature size of a tree to be sure you have enough room. Ask a local nurseryman for suggestions for trees adapted to your area.
  2. Keep the tree well watered and in a shady location until planting. When moving the tree, lift it by the root ball or pot and not by the trunk.
  3. Before planting, remove all wires, labels, cords or anything else tied to the plant. If left on, they may eventually girdle the branch to which they are attached. The root flare (point where trunk and roots meet) should be visible. If it isn’t, remove enough soil or media before planting so that it is.
  4. Dig a proper hole. Make the hole deep enough so that the tree sits slightly above nursery level. Plant the tree on solid ground, not fill dirt. In other words, don’t dig the hole too deep and then add soil back to the hole before placing the tree. The width of the planting hole is very important. It should be three times the width of the root ball. Loosening the soil outside the hole so it is five times the diameter of the root ball will allow the tree to spread its roots faster. 
  5. Remove all containers from the root ball. Cut away plastic and peat pots; roll burlap and wire baskets back into the hole, cutting as much of the excess away as possible. If you can remove the wire basket without disturbing the root ball, do it. If roots have been circling around in the container, cut them and fluff them out so they do not continue growing so that they circle inside the hole and become girdling roots later in the life of the tree. 
  6. Backfill the hole with the same soil that was removed. Amendments such as peat moss likely do more harm than good. Make sure the soil that goes back is loosened – no clods or clumps. Add water as you fill to ensure good root to soil contact and prevent air pockets. There is no need to fertilize at planting. 
  7. Don’t cut back the branches of a tree after planting except those that are rubbing or damaged. The leaf buds release a hormone that encourages root growth. If the tree is cut back, the reduced number of leaf buds results in less hormone released and therefore fewer roots being formed. 
  8. Water the tree thoroughly and then once a week for the first season if there is insufficient rainfall. 
  9. Mulch around the tree. Mulch should be 2 to 4 inches deep and cover an area 2 to 3 times the diameter of the root ball. Mulching reduces competition from other plants, conserves moisture and keeps soil temperature closer to what the plants’ roots prefer.  
  10. Stake only when necessary. Trees will establish more quickly and grow faster if they are not staked. However, larger trees or those in windy locations may need to be staked the first year. Movement is necessary for the trunk to become strong. Staking should be designed to limit movement of the root ball rather than immobilize the trunk. 

Upham and his colleagues in K-State’s Department of Horticulture and Natural Resources produce a weekly Horticulture Newsletter with tips for maintaining gardens and home landscapes. The newsletter is available to view online or can be delivered by email each week.

Interested persons can also send their garden- and yard-related questions to Upham at wupham@ksu.edu, or contact your local K-State Research and Extension office.

Natural needle drop, or plant disease?

(Megan Kennelly, KSU Plant Pathology)

Which of these is a disease, and which is natural needle drop?

If you guessed natural needle drop for the first and disease (Dothistroma needle blight) for the second, you are right!

If you were not sure, here are some resources to figure it out.

In a recent article in Horticulture News, Ward Upham mentioned some recent reports about natural needle drop on evergreens. You can read more about it here:

http://www.ksuhortnewsletter.org/newsletters/natural-needle-drop-on-spruce-arborvitae-and-pines

In addition, this publication talks about pine diseases and at the end there is a section about natural needle drop:

https://www.bookstore.ksre.ksu.edu/pubs/l722.pdf

If you see yellowing, browning, or dropping of needles and you still are not sure you can reach out to your local K-State Research and Extension office or contact the KSU Plant Disease Diagnostic Lab:

Plant Disease Diagnostic Lab

1712 Claflin Road
4032 Throckmorton PSC
Manhattan, Kansas 66506
(785) 532-5810
Fax: (785) 532 5692
clinic@ksu.edu

 

Sharp drop in temperature may be a cause for concern in trees

Western Kansas experienced an extremely sharp drop in temperature recently. Temperatures in some areas of northwest Kansas were near 80 on Wednesday and dropped to near 20 or lower Friday morning. Unfortunately, trees were not hardened off before this happened. In other words, they were not ready for these cold temperatures.

What does this mean? You can read the whole article here in the Horticulture News. Go to this page and scroll down partway:

http://www.ksuhortnewsletter.org/

Tips and tricks on planting trees before you trick-or-treat

(Megan Kennelly, KSU Plant Pathology)

My family did a campfire and cooked our first pot of chili in awhile – it’s really feeling like fall! We have a few weeks remaining in October, and between now and Halloween is still a great time to plant trees and shrubs. Here are some articles with tricks of the trade before you trick-or-treat:

Nice summary from Johnson County:

https://www.johnson.k-state.edu/lawn-garden/agent-articles/trees-shrubs/planting-trees-shrubs-in-fall.html

Excellent nuts and bolts of tree planting:

https://www.bookstore.ksre.ksu.edu/pubs/MF3313.pdf

A few more details on methods:

https://www.bookstore.ksre.ksu.edu/pubs/mf402.pdf

Watering new trees and shrubs:

https://www.bookstore.ksre.ksu.edu/pubs/MF2800.pdf

Now, with all that, truly your most important FIRST step is deciding on what to plant. If you have not yet done your research on that question, here are some more resources on tree and shrub selection.

Trees and shrubs for difficult sites:

https://www.bookstore.ksre.ksu.edu/pubs/MF2205.PDF

Trees for Northeast Kansas:

https://www.kansasforests.org/community_forestry/community_docs/NE%20Kansas%20Preferred%20Trees.pdf

Trees for Northwest Kansas:

https://www.kansasforests.org/community_forestry/community_docs/NW%20Preferred%20Trees122016.pdf

Trees for Southwest Kansas:

https://www.kansasforests.org/community_forestry/community_docs/Pref%20Trees%20SW.pdf

Water-wise plants for south central Kansas:

https://www.sedgwick.k-state.edu/gardening-lawn-care/documents/Water%20Wise%20Plants%202015.pdf

 

 

Goldilocks and the three trees. (Site conditions that are “just right.”)

When it comes to trees:

Trees need water. Not too much, not too little, but just right.

Trees need appropriate temperature. Not too hot, not too cold, but just right.

Trees need to prune. Not too much, not too little, but just right.

If you are looking for some cozy winter reading, you can check out our publication about Tree and Shrub Problems in Kansas.

In addition, I just came across a great publication from University of Kentucky that discusses tree and shrub decline. The information is similar to parts of the Tree and Shrub Problems in Kansas book, but sometimes it is helpful to read information from a new source since everyone presents information in a slightly different way. The reference is Stress and Decline in Woody Plants.

Happy reading!