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Yellow Woodsorrel (Oxalis stricta) Control

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Yellow woodsorrel (Oxalis stricta) is a perennial or annual broadleaf weed that has clover-like trifoliate heart shaped leaves.  Yellow woodsorrel most commonly spreads by seeds that are contained in a capsule that when it explodes ejects the seeds.  It can be confused with clover but has yellow flowers with five petals.  You can find this weed in a wide range of soil conditions and can commonly be confused with black medic, birdsfoot trefoil and white clover. A similar species is creeping woodsorrel but it is most commonly found in landscape plantings while yellow woodsorrel is most commonly found in turf.

To control oxalis, herbicides that contain triclopyr and fluroxypyr are very effective.

 

 

 

 

Herbicides that contain fluroxypyr include;

  • Battleship III
  • Escalade 2
  • Momentum FX2
  • Tailspin
  • Vista XRT

Herbicides that contain triclopyr include;

  • 2-D
  • 4-Speed XT
  • Battleship III
  • Chaser
  • Chaser 2 amine
  • Confront
  • Cool Power
  • Eliminate
  • Horsepower
  • Momentum  FX2
  • Tailspin
  • Three-Way Ester II
  • Turflon Ester Ultra
  • Turflon II amine
  • Triclopyr 4
  • TZONE

Always remember a healthy turfgrass stand through proper maintenance is the best weed control and can help minimize oxalis in your turfgrass.

Information from this post if from “Turfgrass Weed Control for Professionals” To get your copy today click here – https://www.bookstore.ksre.ksu.edu/Item.aspx?catId=545&pubId=20239

Always remember to READ THE LABEL for the correct rate, turfgrass tolerance, and specific instructions before application!!!

***Mention of trade names or commercial products in this article is solely for identification purposes and does not imply recommendation or endorsement, nor is criticism implied of similar products not mentioned by Kansas State University.***

Don’t forget to follow me on twitter @KSUTurf.

Also, visit our facebook page www.facebook.com/KSUTurf

Cool fall weather = large patch season

Here in Kansas we see our most severe large patch symptoms in spring, but we can see it in fall, especially if conditions are cool and wet. Here, also, we’ve had pretty good success at suppressing spring symptoms with applications the prior fall.

We at KSU and others have been busy trying to tackle this disease in recent years, especially with the increasing interest in zoysia. For a review of research across the transition zone you can check out this article in Golfdom:

Don’t get overmatched: Dispatch that large patch

 

Dollar spot activity, and lingering brown patch

Moderate days and cool, dewy nights have increased dollar spot pressure. Check out these photos in our research plots.

Here is an untreated plot:

Here is a cleaner plot:

There are many great tips about fungicides for managing dollar spot starting on page 15 of this document:

http://www2.ca.uky.edu/agcomm/pubs/ppa/ppa1/ppa1.pdf

In terms of varieties, like other universities, KSU does a lot of screening of new breeding lines and existing cultivars. In our research plots we like to have big blocks of different cultivars for different reasons. In my fungicide trials, often I like to use susceptible varieties to make sure we get strong disease pressure. For other types of studies we like to use more resistant varieties when developing reduced-input integrated management strategies.

Here is an example of two varieties out on one of our research greens. They have not been sprayed, and they are not in use at the moment, but they show the striking differences in susceptibility:

I also noticed a tiny bit of lingering brown patch on our putting green. When we switch more solidly into cool fall weather that should fade into nothing. Ah, fall! Let’s have more nights in the 50’s!

If you squint hard, you’ll see the big brown patch circle among all the dollar spot:

Support the KSU Turfgrass Students and Have Fun!

Come out on September 30th to Colbert Hills Golf Course and play in the Kansas State University Golf Course Superintendent Student Chapter Fundraiser Golf Tournament!

This is a great way to show your support to the future of the turf industry and the students all while having some fun on the golf course.

If you can’t make it show your support by sponsoring a hole.

See information about signing up below!.

Future of Turf 2018 on Sept. 6, 2018 – Hosted by Corteva Agriscience (Dow AgroSciences)

Corteva will be hosting the Future of Turf 2018 on Sept. 6, 2018, from 1 to 3 p.m., at Kansas State University’s Rocky Ford Turf Research Center. At the FREE educational field day, you will get a preview of our groundbreaking new products, GameOn™ and Relzar™ specialty herbicides, which will use a new chemistry to control tough weeds like never before.

This technical event, located at 1700 Barnes Road, Manhattan, KS 66502, will include hands-on demonstrations and cover technical topics like understanding mixing and handling, recognizing turf injury, importance of flexible application timing and more.

Signup here – http://engage.corteva.com/FutureOfTurf

For more information, please contact Dow AgroSciences Territory Manager Colleen Derksen at 317-691-6982 or via email at cmderksen@dow.com.

 

What do you do well that nobody else does?

(Megan Kennelly, KSU Plant Pathology)

At the Kansas Turf Conference on December 4, 5 & 6, 2018 in Topeka we will have a new booth in the exhibit area for YOU to show off your best innovations!

Do you have a piece of equipment that you hacked together on your own? Something that saves you headaches? Are you willing to share your idea? If so – send me a quick photo and description. I’ll display it at the booth, with credit to you.

How about a method? Do you have a special knack for motivating your crew or co-workers? Write that down, and we can share it.

What about an innovative way to reach out to customers?

If you have a special tip or trick you are willing to share, send it my way. You can email me at kennelly@ksu.edu

At the booth we’ll have people vote on their favorite innovation, with a special prize for the winner!

Fungi thriving in wet conditions

(Megan Kennelly, KSU Plant Pathology)

Fungi love wet, humid conditions. Parts of Kansas have received a lot of moisture lately.

Here are a few recent examples:

Brown patch mycelium on a morning with fog and dew. If you look closely you’ll see the lesions, too.

 

 

Here is some foliar Pythium mycelium from another wet site:

You can see the white mycelial threads if you look closely. Also notice how the turf is so matted down and soggy/greasy in appearance.

At this location they had just sprayed tebuconazole, so how did the Pythium keep on rolling? Well, as you might remember, Pythium is not a true fungus, and some fungicides just do not work on it. Fungicides in the tebuconazole family (the DMI fungicides, FRAC code 3) have no effect on Pythium – you might as well be spraying water. For a list of products that DO have efficacy on Pythium foliar blight you can check this reference (p. 23) http://www2.ca.uky.edu/agcomm/pubs/ppa/ppa1/ppa1.pdf

Cultural practices are outlined HERE.

Conditions for both Pythium and brown patch “should” be ending soon, and cool fall weather alone acts as a natural fungicide to slow those 2 diseases down just as our cool-season grasses find themselves in optimal conditions to grow. Recovery and seeding season is right around the corner.

And, finally, after 4 inches of rains there were mushrooms everywhere:

Some mushrooms are associated with fairy rings, and there is some information about that HERE.

How do mushrooms pop up overnight? They are actually kind of pre-made, hanging out in the soil in a small egg-like structure. When moisture comes they can expand quickly, like one of those sponge-animals that expands when you put it in a bucket. There are lots of time-lapse videos out there that show mushroom growth – here is one example:

It’s kind of cool but creepy at the same time.

KGCSA Legacy Scholarship – due August 27

The KGCSA Legacy Scholarship offers educational aid to the children and grandchildren of KGCSA members.  A $1,000 scholarship will be awarded. Applications are due August 27, 2018.

Eligibility
1. One or more of the applicant’s parents or grandparents must have been a KGCSA member for five or more consecutive years and must be a currently active.

2. The student must be enrolled full-time at an accredited institution of higher learning, or in the case of high school seniors, must be accepted at such an institution for the next academic year. Graduating high school seniors must attach a letter of acceptance to their application.

3. Past winners are ineligible to apply the following year. They may reapply after a one-year hiatus.

Criteria for Selection
1. Applicants will be evaluated based on academic achievement, extracurricular and community involvement, leadership and outside employment.

2. The student must submit an original essay of up to 500 words.

You can download the application at www.kgcsa.org

White Clover Control

(By Jared Hoyle, KSU Turfgrass Research and Extension)

School is starting back and college football is right around the corner.  This tells me it is the best time of the year to start renovating, overseeding or establishing new cool-season turfgrass areas. But before you do that, you might have some unwanted weeds to get rid of.  White clover is one of the most common weeds found in cool-season turfgrass.  It can grow in a wide range of environmental conditions and can tolerate many of our cultural practices.   It can also spread by seeds and by stolons.

White clover is a perennial broadleaf weed that has trifoliate leaves that may or may not have a wedged-shaped mark. Although it is called white clover the flowers are white but may turn pink as they age.

Because white clover can fix its own nitrogen some see it as an important species to add beneficial soil nitrogen.  There had been some work done to explore using both clover and turfgrass in a mixture in their lawns.  Others may consider it as a weed.

If you consider it a weed, fall is a great time to try and control it.  But did you know 2,4-D, glyphosate and sulfentrazone do not control white clover?  For best control herbicides that contain clopyralid, dicamba, fluroxypyr, florasulam, metsulfruon, and/or quinclorac (also controls crabgrass) provide the best control when applied in the fall.

Always remember a healthy turfgrass stand through proper maintenance is the best weed control and can help minimize clover in you turfgrass.

Information from this post if from “Turfgrass Weed Control for Professionals” To get your copy today click here – https://www.bookstore.ksre.ksu.edu/Item.aspx?catId=545&pubId=20239

Always remember to READ THE LABEL for the correct rate, turfgrass tolerance, and specific instructions before application!!!

***Mention of trade names or commercial products in this article is solely for identification purposes and does not imply recommendation or endorsement, nor is criticism implied of similar products not mentioned by Kansas State University.***

Don’t forget to follow me on twitter @KSUTurf.

Also, visit our facebook page www.facebook.com/KSUTurf