Kansas State University


K-State Turfgrass

Cut down and destroy dead pines to help prevent spread of pine wilt

Now you see it:


Now you don’t:


This tree had pine wilt disease, and it was cut down and chipped or burned to reduce the risk of spread to other trees.

Pines have several disease and insect problems. One of them is pine wilt disease. It kills the entire tree quickly.

Pine wilt is caused by the pinewood nematode, a microscopic worm. The nematode is spread by the pine sawyer beetle. The nematode feeds and multiplies in the tree’s resin canals, causing wilting and death in several weeks to several months. The nematode and beetles spend the winter in the infected tree. In spring, the beetles emerge starting around May 1, carrying nematodes to new trees and continuing the cycle of infection.

The disease is common in the eastern half of the state and has gradually spread west. There have been pockets of infection in the western part of the state, but we’d like to keep it out. Also, sanitation efforts will help reduce spread even in the east where the disease is common. Here is a map of pine wilt from our Kansas Department of Agriculture colleagues based on recent survey data:


 In Kansas, new pine wilt infections are most visible from August to December. Trees wilt and die in a short period of time, from several weeks to a few months. In the first stages, the needles turn grey or green, then yellow and brown. The discoloration sometimes occurs branch by branch, sometimes all at once. With pine wilt, eventually the whole tree dies, within a few months. The brown needles stay on the tree for up to a year after the tree has died. Another key symptom is reduced resin. On a healthy tree, sticky resin bleeds from the site of a wound. In contrast, if a tree has pine wilt the resin is often reduced or absent, and branches become dry or brittle.

There is a website with color photos and descriptions at the following link:


There are images to compare and contrast pine wilt with other pine diseases here:


With the other diseases (tip blight, needle blight) only parts of the tree turn brown. With pine wilt, the whole tree is brown and dead.

If you aren’t sure if your tree has pine wilt or something else, contact your local K-State Research and Extension Office or the K-State Diagnostic Lab (clinic@ksu.edu).

If a tree has pine wilt,  the tree should be cut down by  April 1  to make sure there is time to destroy the wood by May 1, when the beetles start to some out. Cut the tree to the ground—don’t leave a stump. Chip or burn the wood immediately to destroy the beetles and nematodes. Don’t keep pine wood around for firewood.

Volunteers Needed for Irrigation Installation at Rocky Ford Turf Research Center

K-State’s turfgrass research group is starting a high profile project in cooperation with the USGA and the Toro Co, and we need your help!

The goal of the project is to improve the use of soil moisture sensors to control irrigation while minimizing water applications and maintaining good quality turf.  This will require 3 years of intensive study of the science of using these sensors.

However, before we can do that, we need to install an in-ground irrigation system.  That is where we need your help!  We are organizing work days at the Rocky Ford Turfgrass Research Center on Friday, March 23 and Saturday, March 24.  All the irrigation supplies are in-hand and we are working on getting a trencher.  Bayer has indicated they will sponsor lunch on Friday and we are working on getting sponsors for lunch on Saturday.

This irrigation system will be used for years to come, well beyond the 3-year study, and all turfgrass managers will benefit from the research.  Therefore, we would be most grateful for any time you could contribute, whether it is for 1 or both days.

Please email Christy Dipman at cdipman@ksu.edu to let her know what day(s) you will be available to assist with the installation.

Large patch activity in research plots

Cool, wet weather has triggered large patch activity in golf courses – and in our research plots.

The photos below are from an ongoing research trial. You can read some details about the study in our online research update from spring. PhD student Mingying Xiang is the lead researcher on this study, under the mentorship of Megan Kennelly and Jack Fry.

The photos below show different zoysiagrass breeding lines. For each plot, one side was inoculated in Sept 2016, and the other side is protected with fungicides to allow ongoing rating of quality and agronomic traits in the absence of disease AND to serve as a “healthy check.”

As you glance through the photos, you can clearly see the large patch on the inoculated sides of many of the plots, while the fungicide-treated side is clean. However, you will also see plots where you can’t even tell which side is which. That is, even the inoculated, non-fungicide-treated side is looking clean. We are hoping those  may be resistant lines to examine in further testing. Stay tuned! Turfgrass breeding takes a long time!

The Kansas Turf Conference is coming up!

The annual Kansas Turfgrass Conference is coming up in about 6-7 weeks. If you have not yet checked out the program you can read it here.

As you’ll see, hot topics include weeds, insects, water, light, diseases, business, and more!

We have a great slate of speakers coming from other states as well. Be sure to register, and we’ll see you in Topeka!

Congratulations to Mingying Xiang for earning national turfgrass science award

KSU PhD student Mingying Xiang is one of this year’s recipients of the prestigious Chris Stiegler Travel Award. She will formally receive the award next week at the annual meeting of the Crop Science Society of America/American Society of Agronomy/Soil Science Society of America.

Congratulations Mingying! She is recognized for her academic achievements in the classroom, research accomplishments, and leadership activities.

Mingying’s research is focused on evaluating zoysiagrass breeding lines for cold hardiness, quality, and resistance to the disease large patch along with studying the potential for tall fescue-zoysiagrass blends to reduce the disease brown patch while maintaining overall summer quality.



Fall aerification to reduce problems in 2018

Got thatch?

If you are not sure what the thatch situation is on a site you manage, go take a look. Take a trowel, pocket knife, or soil probe, and poke around. If it’s starting to build up in your cool-season turf, take action now. You don’t want a thatch problem to bite you in summer 2018.

Here are some tips in this Fact Sheet about Thatch

Similarly – does your putting green soil look like a layer cake?

As we’ve said before here, a suboptimal rootzone is a pre-existing condition in putting greens.

Take advantage of this great fall weather to do all you can to promote healthy roots in 2018.

Last hiccups of summer diseases

Early last week we saw a couple last gasps of the summer diseases, with some Pythium on a tall fescue lawn:

It was greasy, it was mushy, and after “a night in the box” there was classic Pythium mycelium. Foliar Pythium is rare on tall fescue lawns, usually coming in during very wet weather on sites that have received a little too much water and perhaps a little too much N. When this one came in, it was after one last blast of some heat, but with cool, cool temps on the horizon. Now that we are coming into this nice, consistent cool weather it’s really too late to consider fungicides, and instead we can concentrate on fall renovations AND tweaking cultural practices to help reduce disease risk next year. There was also a last hiccup of brown patch from a golf course fairway. Same story – with lows in the low 60s and even 50s, those diseases should stay quiet and hopefully we won’t see them until 2018.

Next door in Missouri, Dr. Miller is reporting some continued sightings of Pythium root rot (which is different from foliar Pythium) and basal anthracnose. I would agree we are not out of the woods yet. You can see his photos HERE.