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Tag: grassy weeds

Two-Minute Turf Extension Video: Impact of Nitrogen on Weed Encroachment

Posted on by Jack Fry

This new blog video gives an update on a research project, a turf-related issue, or current concerns in the turf industry.  Each one will be approximately 2 minutes long – you’ll see one periodically!

On this video, the first one, see the impact of nitrogen fertilization on crabgrass encroachment in a field project at the Olathe Horticulture Center.  This study is being done at several universities in the north central U.S. including Iowa State, Michigan State, Minnesota, Missouri, Nebraska, North Dakota State, Ohio State, and Wisconsin.  Most are looking at weeds in cool-season grasses, but you’ll hear about bermudagrass here.

CLICK HERE TO VIEW

 

 

 

Tips for Enhancing Efficacy of Preemergence Herbicides

Posted on by Jack Fry

By Dr. Jack Fry

Preemergence herbicide applications for crabgrass, goosegrass, foxtail, and other annual grasses are underway.  Here are some bullet points to consider to increase the efficacy of the herbicide you use.

Maintain turf density and mow higher.  Good turf density resulting from proper cultural practices for the grass you’re managing reduces encroachment of all weeds, including annual grasses.  Mowing at the higher end of the recommended range has consistently shown significantly lower populations of crabgrass and other annual grasses than mowing at lower mowing heights.

Apply before emergence.  Not all annual grass species emerge at the same time.  For example, goosegrass emerges later than crabgrass.  However, even within a species, emergence of new seedlings occurs throughout spring and summer.  With most preemergence herbicides, when seedlings have emerged, they will not effectively control those plants.  However, the application will control emergence of grasses beyond that date.  Dithiopyr (Dimension) does provide control of crabgrass that has emerged but has not begun to produce tillers.

Use effective strategies to guide application.  Calendar dates, soil temperature, flowering of ornamentals, and other strategies are all used to help guide applications and maximize herbicide residual during the period annual grasses emerge.  Here are a couple of articles related to this subject:

https://blogs.k-state.edu/turf/methods-of-predicting-crabgrass-emergence/

https://blogs.k-state.edu/turf/flowering-ornamentals-and-crabgrass-emergence/

Apply uniformly.  Uniform application is critical – just like distributing paint evenly over your house is aesthetically pleasing.  If you leave a section of the house unpainted, it’s clearly visible.  Good annual grass control requires uniform application; if an area is not treated, it’s likely you’ll seed weed emergence there. Uniform application is achieved by proper spreader or sprayer calibration, colorants that indicate areas that have been treated with liquid products, and applying the product in two directions (half rate in each).

Split applications.  Preemergence herbicides generally provide better suppression of annual grasses when applications are split (1/2 rate each application), usually 6 to 8 weeks apart.  This allows a higher level of herbicide presence on the soil surface, which will minimize weed emergence.  Here’s an article from Purdue on this subject:

https://turf.purdue.edu/wp-content/uploads/2012/06/15_AGRY_Patton_sequential20apps.pdf

Water in after application.  For preemergence herbicides to be activated and ensure uniform distribution on the soil surface, irrigation (or rainfall) after application is needed.

Find more information on weed control by clicking on the tags on the blog (left column), such as “weed control,” “crabgrass,” etc., or search by category on the right side of the page.

***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 the K-State Turf and Landscape Team on Twitter @KSUTurf

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

Bermudagrass Control Options for Reseeding

Posted on by jahoyle

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Last week Ward Upham wrote an article on bermudagrass control in the KSU Horticulture Newsletter.  In the article below he explains the difficulty of controlling bermudgrass, the process and the multiple applications of a non-selective herbicide.

Bermudagrass Control by Ward Upham

Bermudagrass can make a nice lawn if you don’t mind its
invasiveness and short growing season. But many people dislike both
these characteristics. Warm-season grasses, such as bermudagrass,
zoysiagrass and buffalograss, green up later than cool-season grasses
such as tall fescue and Kentucky bluegrass. They also go dormant earlier
in the fall, which can make a lawn unattractive. Bermuda that invades a cool-season lawn will be brown during much of the spring and fall while the tall fescue portion of the lawn is green. Bermuda is much more drought and heat resistant than cool-season grasses, so it will take over a cool-season lawn during the summer months if it is in full sun.

So, how do you control bermudagrass that has invaded a cool-season
lawn? Research conducted in 1996 showed that glyphosate is the best herbicide for the job. Glyphosate is a nonselective herbicide and will kill everything—
including tall fescue or Kentucky bluegrass. Therefore, you will need to
reseed treated areas. In our study, we applied a 2% solution of
glyphosate on July 15 and again on August 15 on a bermudagrass plot that
was more than 15 years old. More than one year later, we saw no
regrowth. Glyphosate works best if bermuda is growing well. The better
the bermudagrass is growing, the more chemical is taken up and pushed
into the roots. Water and fertilize if needed to get it going.
Spray about the middle of July (or when the bermuda is growing
well). Use glyphosate (2% solution). Wait two weeks and scalp the lawn
(mow as low as possible and remove clippings.) This will prevent dead
grass from covering any bermuda that starts to recover. Wait another two
weeks and spray again with glyphosate if there is any green. Wait two
more weeks and reseed. (Ward Upham)

(For the KSU Horticulture Newsletter click here – https://hnr.k-state.edu/extension/info-center/newsletters/index.html)

But during this time areas are dead, may not be acceptable and re-seeding must be done in the fall.  What if you are wanting to seed in the spring (Especially if you ware wanting to convert to buffalograss)? This process might not work due to the timeline. Therefore, a couple years ago we looked into some other options and combinations for bermudagrass control. Here is a brief overview of the project.

Multiple summer applications of glyphosate are commonly recommended for bermudagrass (Cynodon spp.) control. However, this regime results in an extended period of displeasing and nonfunctional turfgrass, and is not ideal for spring establishment. An autumn glyphosate application prior to winter dormancy can control bermudagrass and may benefit spring  establishment projects. However, research is needed to more precisely define the parameters of efficacious late-season herbicide applications for bermudagrass control as it transitions into dormancy. Therefore, our objective was to examine late-season bermudagrass removal using combinations of glyphosate, fluazifop, and mesotrione. Experiments were initiated in October 2013 at the Rocky Ford Turfgrass Research Center in Manhattan, KS, on mature ‘Midlawn’ hybrid bermudagrass, and at Stagg Hill Golf Course in Manhattan, KS, on mature common bermudagrass. Seven herbicide treatments containing combinations of glyphosate, fluazifop, and mesotrione were evaluated. Green bermudagrass cover (0–100%) was visually estimated when treatments were applied and every 14 d after application. Only treatments containing glyphosate reduced the green cover of bermudagrass at each site the following year. Across all ratings dates and locations, adding mesotrione, fluazifop, or both to glyphosate did not further reduce green bermudagrass cover. Overall, results indicate that a single autumn application of glyphosate prior to bermudagrass dormancy reduces bermudagrass cover the following spring. The significant reduction at spring green-up may allow turf managers to make additional applications in the spring for increased control before spring establishment.

For the full article;

Hoyle, J.A.,C. Braun, C.S. Thompson and J.A. Reeves. 2018. Late-Season Bermudagrass Control with Glyphosate, Fluazifop, and Mesotrione Combinations. Agrosystems, Geosciences & Environ. 1:180014 (2018) doi:10.2134/age2018.06.0014

https://dl.sciencesocieties.org/publications/age/pdfs/1/1/180014

***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

Postemergent Crabgrass Control

Posted on by jahoyle

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Today I was walking around the Rocky Ford Turfgrass Research Center in Manhattan, KS looking for an area to put out a postemergent crabgrass study and notice that the crabgrass on the research farm is all different stages.  It is important to know what stage the crabgrass is in to help with control.  That could determine your success in controlling it with postemergent herbicides

There are postemergent herbicide options out there for crabgrass control.  But depending on how big or how many tillers the crabgrass has will help you determine what product to use.  First, determine the size or stage of crabgrass you have present.

Here is a picture to show the tillering stages of crabgrass.

The smaller the crabgrass the easier it is to kill it.  The tillered crabgrass may take more than one application and higher rates so make sure you check the label for correct application rates and intervals.

  • dithopyr – Can provide control to crabgrass up to one tiller stage.  This product also has preemergence activity.
  • quinclorac – Can be applied on most cool- and warm-season turfgrass species.  This product controls crabgrass when it is one tiller or smaller or when it has four or more tillers.
  • mesotrione – Can be effective for crabgrass control but in most cases will take two applications at two week intervals. The label also states that applications must be made before the four tiller crabgrass stage.
  • topramazone – Similar to mesotrione, this product will require two applications at three week intervals. Use at higher rates on crabgrass that have greater than one tiller.
  • fenoxaprop – Are very effective in controlling crabgrass.  Label states that this product can be applied to annual grasses up to the five tiller stage. Remember not to tank mix with products that contain 2,4-D, antagonism can occur.

As one last reminder, do not apply post emergent herbicides outside the recommended temperature on the label.  This will increase the risk of turfgrass injury.

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

Research UPDATE – Influence of Herbicide Combinations and Sequential Applications on Windmillgrass (Chloris verticillata) Control

Posted on by jahoyle

(By Nic Mitchell and Jared Hoyle, KSU Turfgrass Research and Extension)

Windmillgrass (Chloris verticillata Nutt.) populations commonly infest turfgrass systems in the mid-west, which result in aesthetically unacceptable turfgrass stands. Windmillgrass is a perennial monocot bunch-type grass. It often spreads by stolons and by its panicle shape seed which acts much like tumble weed.

Prior research found that Pylex (topramezone) and Acclaim Extra (fenoxaprop) result in fair to minimal control of windmillgrass with a single application. Tenacity (mesotrione) which, labeled for two applications for best control of windmillgrass, recommends the second application should be three weeks after initial application. Additionally, studies have shown the addition of triclopyr to HPPD inhibitor herbicides increases windmillgrass control in a controlled environment.

The goal of this research was to determine the effect of a sequential postemergent herbicide applications and the addition of triclopyr to HPPD inhibitors herbicides on windmillgrass control.

Research trials were initiated in 2018 at Rocky Ford Turfgrass Research Center in Manhattan, Kansas. Windmillgrass was infested in a low maintenance tall fescue (Schedonorus arundinaceus) system. Seven herbicide combinations were applied as a single application or with a sequential application and non-treated control was included for comparison for a total of 15 individual treatments. All herbicide treatments were applied on August 16, 2018 and treatments that received a sequential application were applied on September 9, 2018. Herbicide treatments consisted of Pylex (topramezone) at 2 fl oz/a, Tenacity (mesotrione) at 8 fl oz/a, Acclaim (fenoxaprop) at 39 fl oz/a, Alligare Triclopyr 4 (triclopyr) at 32 fl oz/a, Pylex (topramezone) at 2 fl oz/a + Alligare Triclopyr 4 (triclopyr) at 32 fl oz/a, Tenacity (mesotrione) at 8 fl oz/a + Alligare Triclopyr 4 (triclopyr) at 32 fl oz/a, Acclaim (fenoxaprop) at 39 fl oz/a + Alligare Triclopyr 4 (triclopyr) at 32 fl oz/a, and a nontreated control. Data collection consisted of visual percent windmillgrass cover (0-100%) and were transformed to percent windmillgrass control for presentation purposes. Analysis of variance (ANOVA) was performed in SAS 9.4 (SAS Institute Inc., Cary, NC) and means were separated according to Fisher’s protected least significant difference (LSD) level at 0.05.

We found that Pylex (topramezone) applied at 2 fl oz/a resulted in 87% windmillgrass control at 8 weeks after treatment. A single application of Pylex (topramezone) at 2 fl oz/a + Alligare Triclopyr 4 (triclopyr) at 32 fl oz/a and Tenacity (mesotrione) at 8 fl oz/a + Alligare Triclopyr 4 (triclopyr) at 32 fl oz/a resulted in 96% and 97% windmillgrass control 8 weeks after initial treatment, respectively. All treatments that received a sequential application on September 9, 2018 excluding the non-treated control and Acclaim (fenoxaprop) at 39 fl oz/a provided 100% windmillgrass control at 8 WAT. Acclaim (fenoxaprop) at 39 fl oz/a applied on August 16, 2018 followed by an application at 39 fl oz/a on September 9, 2018 resulted in 88% windmillgrass control.

Table 1. Windmillgrass (Chloris verticillata Nutt.) control 8 weeks after initial application from single and sequential applications at Rocky Ford Turfgrass Research Center in Manhattan, KS; 2018.

Treatment Herbicide Rate Application Date Controla
___%___
1 non-treatedb – – 4 Cc
2 Pylex + MSOd 2 fl oz/a + 1% v/v Aug. 16, 2018 87 A
3 Tenacity + NISd 8 fl oz/a + 0.25% v/v Aug. 16, 2018 9 C
4 Acclaim Extra + NIS 39 fl oz/a + 32 fl oz/100 gal Aug. 16, 2018 16 C
5 Triclopyr 32 fl oz/a Aug. 16, 2018 64 B
6 Pylex + Triclopyr + MSO 2 fl oz/a + 32 fl oz/a + 1% v/v Aug. 16, 2018 96 A
7 Tenacity + Triclopyr +NIS 8 fl oz/a + 32 fl oz/a + 0.25% v/v Aug. 16, 2018 97 A
8 Acclaim Extra + Triclopyr +NIS 39 fl oz/a + 32 fl oz/a + 32 fl oz/100 gal Aug. 16, 2018 63 B
9 Pylex + MSO 2 fl oz/a + 1% v/v Aug. 16, 2018 fbe Sept. 9, 2018 100 A
10 Tenacity + NIS 8 fl oz/a + 0.25% v/v Aug. 16, 2018 fb Sept. 9, 2018 100 A
11 Acclaim Extra + NIS 39 fl oz/a + 32 fl oz/100 gal Aug. 16, 2018 fb Sept. 9, 2018 88 A
12 Triclopyr 32 fl oz/a Aug. 16, 2018 fb Sept. 9, 2018 100 A
13 Pylex + Triclopyr + MSO 2 fl oz/a + 32 fl oz/a + 1% v/v Aug. 16, 2018 fb Sept. 9, 2018 100 A
14 Tenacity + Triclopyr +NIS 8 fl oz/a + 32 fl oz/a + 0.25% v/v Aug. 16, 2018 fb Sept. 9, 2018 100 A
15 Acclaim Extra + Triclopyr +NIS 39 fl oz/a + 32 fl oz/a + 32 fl oz/100 gal Aug. 16, 2018 fb Sept. 9, 2018 100 A

a Ratings were conducted 8 weeks after initial application; October 11, 2018.

b Non-treated control contained approximately 65% windmillgrass cover throughout the research trial. 4% control was observed due natural declining of windmillgrass populations to environmental considerations on October 11, 2018.

c Treatment means followed by a common capital letter are not significantly different according to Fisher’s protected LSD (α= 0.05).

d MSO, methylated seed oil and NIS, non-ionic surfactant were added to treatments according to herbicide manufacture recommendations.

e fb, followed by.

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

NEW – Turfgrass Weed Control for Professionals – 2019

Posted on by jahoyle

(By Jared Hoyle, KSU Turfgrass Research and Extension)

With new herbicides entering the market, new techniques for controlling weeds, and with more and more difficult to control weeds the “Turfgrass Weed Control for Professionals” manual has been updated to address many of these issues.  Check out the 2019 edition!  It is a must have for every turfgrass manager!

To get your copy click here – https://www.bookstore.ksre.ksu.edu/Item.aspx?catId=545&pubId=20239

 

More than you ever want to know about preemergent herbicides

Posted on by jahoyle

(by Jared Hoyle, KSU Turfgrass Research and Extension)

Ever year I write a blog, a newsletter article, send out a tweet and post on Facebook about applying preemergent herbicides for summer annual grass control. We are typically most concerned with crabgrass so I went back and searched through the blog posts and articles and believe it or not it is all still relevant information! Not much has changed, so for this article I am going to spotlight information across these articles and compare from when I originally wrote it.

Crabgrass emerging in bare ground earlier than turf

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Up first, Methods of Predicting Crabgrass Emergence! In this article I go over the different methods to predict when crabgrass emerges; calendar date, soil temperatures, forsythia blooms, growing degree days. Like last year we have had a fluctuating Spring. In the article from March 14, 2017 I stated that it was 80 deg F on the 12th and was snowing just a couple days before. Sound familiar? Refresh yourself on the different methods and know its not too late to get preemergence herbicides out.

https://blogs.k-state.edu/turf/methods-of-predicting-crabgrass-emergence/

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Next article is for all you golf course turfgrass managers. Preemergence Weed Control in Bentgrass Putting Greens. This article was also from March 2017 and I went through what preemergent herbicides are available to use on bentgrass putting greens. The list of herbicides was from the Turfgrass Weed Control for Professionals 2017 Manual (https://mdc.itap.purdue.edu/item.asp?Item_Number=TURF-100). Going through the 2018 edition…. Guess what again? Not much has changed for use on putting greens but I would encourage you to check out the manual and read the “Tips for Herbicide Use on Golf Course Putting Greens” section on page 108.

https://blogs.k-state.edu/turf/preemergence-weed-control-in-bentgrass-putting-greens/


And now one of my favorite quotes from Benjamin Franklin “An ounce of prevention is worth a pound of cure”. This was the lead in for talking about why preemergent herbicides are worth it! This article talks about what weeds preemergent herbicides work on, how they work, and the growth stages of crabgrass. To “round-up” the article I put a list of options out there, the weeds these preemergent herbicides control and some concerns/comments. One thing that I did not list is the combination products. I only listed the single active ingredients.   There are many combination products as well. (Maybe that will be the next blog post – Combination Preemergent Herbicides.)

https://blogs.k-state.edu/turf/an-ounce-of-prevention-is-worth-a-pound-of-cure-by-benjamin-franklin-that-goes-for-preemergence-herbicides-too/

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.***

Stinkgrass

Posted on by jahoyle

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Many people like the smell of freshly cut grass but there is a weed out there that is common in many lawns in KS called stinkgrass and it stinks.  It stinks cause it is a weed and it also literally stinks.

Stinkgrass sometimes referred to as stinking lovegrass or candy grass is a summer annual grassy weed that was introduced from Europe. This weed is most noticeable when the grayish-green triangular shaped panicle type seedhead is present. The seedhead closely resembles that of the bluegrass family and may cause confusion in identification. Individual spikelets, however, possess a grayish-silver, sometimes purple color and at times may appear waxy.

The leaves are smooth, glossy below and rough on top typically ranging from ¼ to ½ inch wide. The stem of the plant is jointed with slightly swollen nodes, occasionally with a 45 degree bend near the stem base.To vegetatively identify stinkgrass, look at the ligule, the sheath and back of the leaf blade where it attaches to the collar. The ligule is a short fringe of hairs, with several long hairs at the outer edge.

Another distinctive characteristic of stinkgrass is that it produces a bitter pungent odor, most noticeable when the tissue is crushed or mowed, hence the name stinkgrass. It is said to be poisonous to livestock, particularly horses, but most animals avoid grazing it because of the odor. Stinkgrass normally spreads by seed dispersal which emerges in late spring a few weeks after crabgrass or at a similar time to goosegrass. Maximum germination occurs when soil temperatures remain above 65°F for several weeks. Mature this plant will grow from 1 to 2 feet tall and it can temporarily survive mowing heights typical for home-lawns.

Occurrence

In general, stinkgrass is not a persistent problem in lawns but commonly occurs in newly established or poorly maintained lawns and low maintenance areas like roadsides that were once cultivated as agricultural land. It can also be a problem in newly planted sod fields. It has a shallow fibrous root system and is normally not a problem in properly maintained turf the second year after planting.

Non-Chemical Control

Stinkgrass can be very easily removed by hand. In newly established lawns, however, practices to promote maximum density of the desirable turf species like adequate fertility, proper mowing and irrigation will eventually crowd out this weed. Stinkgrass will die after the first killing autumn frost allowing a vigorous desirable turf species to fill the voids.

Chemical Control

No specific pre-emergence herbicides are labeled for turf use, though most common pre-emergent herbicides suitable for crabgrass and goosegrass should also be effective on stinkgrass without injury to the desired turf species. The only compounds labeled for post-emergent control are glufosinate (Finale) or glyphosate (Round-up). Both of these herbicides are non-selective herbicides which kill all green plants and should not be applied to desirable turfgrasses. Once the stinkgrass has been controlled, however, these areas can then be reseeded or sodded.

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

Homeowner Do-It-Yourself Lawn Calendar for Warm-Season Grass

Posted on by jahoyle

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Last week I got a lot of good feed back on the Homeowner Do-It-Yourself Lawn Calendar for Cool-Season Grasses so I decided that it would be good to go ahead and get the warm-season lawn calendar out there for everyone that is manageing zoysiagrass, bermudagrass or buffalograss.

The following is a lawn calendar for zoysiagrass and bermudagrass. Buffalograss, also a warm-season grass, but we will cover that separate because the management of buffalograss is a little different then zoysiagrass and bermudagrass.

Zoysiagrass and Bermduagrass Lawn Calendar

March
Spot treat broadleaf weeds if necessary. Treat on a day that is 50 degrees F or warmer. Rain or irrigation within 24 hours of application will reduce effectiveness.

April
Apply crabgrass preventer between April 1 and April 15, or apply preventer when the eastern redbud is in full bloom. This year we are getting a little warmer sooner but remember this cold snap that we just had would have killed any crabgrass if it had germinated. If using a product with prodiamine (Barricade), apply two weeks earlier. Crabgrass preventers must be watered in before they will start to work.

May – August 15
Fertilize with 1 lb. of nitrogen per 1,000 square feet per application. Follow the recommendations on the bag. More applications will give a deeper green color, but will increase mowing and may lead to thatch buildup with zoysiagrass. Bermudagrass can also have problems with thatch buildup but thatch is less likely with Bermuda than zoysia. Bermudagrass – Use two to four applications. Zoysiagrass – Use one to two applications. Too much nitrogen leads to thatch buildup.

One Application: Apply in June.
Two Applications: Apply May and July.
Three Applications: Apply May, June, and early August.
Four Applications: Apply May, June, July, and early August.

Remember to look and see if you are using a quick release nitrogen source or a slow release nitrogen source.  If you use a quick release source then it is immediately available but only lasts a couple weeks.  Thats why you would have to make a couple of applications like it is listed above.  If you are going to use a slow release source it will tell you on the bag how long the product will last.  Therefore, you might not have to make as many applications.

So generally you want to use a total of 2 to 4lb. of nitrogen per 1,000 square feet per year for bermudagrass and 1 to 2 lb. of nitrogen per 1,000 square feet per year for zoysiagrass.

June
If grubs have been a problem in the past, apply a product containing imidacloprid by mid July. Imidacloprid can be applied as early as mid May if there are problems with billbugs or May beetle grubs. These products kill the grubs before they cause damage. They are effective and safe but must be watered in before they become active. June is a good time to core aerate a warm-season lawn. Core aeration will help alleviate compaction, increase the rate of water infiltration, improve soil air exchange and help control thatch.


Late-July through August
If you see grub damage, apply a grub killer. If Imidacloprid has been applied, this should not be necessary. Grub killers must be watered in immediately.

Late October
Spray for broadleaf weeds if they are a problem. Treat on a day that is at least 50 degrees F. Rain or irrigation within 24 hours reduces effectiveness. Use the rates listed on the label for all products mentioned.

 

Buffalograss Lawn Calendar

Buffalograss has become more popular in recent years due to its reputation as a low-maintenance grass. Buffalograss does require less water and fertilizer than our other turfgrasses but often has problems competing with weeds in eastern Kansas. Remember, buffalograss is a low-maintenance lawn and not a “No”-maintenance lawn.

Buffalograss is an open growing grass that will not shade the soil as well as most of our other turfgrasses. Weeds are often the result. A regular mowing schedule can reduce broadleaf weed problems as most broadleaves cannot survive consistent mowing. Those that do either have a rosette growing pattern (dandelions, shepherds purse) or are “creepers” (henbit, chickweed, spurge). Annual grasses such as crabgrass or foxtail can also be a problem. A good weed preventer (prodiamine, pendimethalin or dithiopyr) may be needed prevent problems.


March

Spot treat broadleaf weeds if necessary. The most important treatment for broadleaf weeds should be in late October to early November well after the buffalograss is dormant. Treatments are much more effective then than in the spring as the weeds are smaller and the weeds are sending energy, as well as the herbicide, to the roots. Treatments in March are to take care of any “escapes” missed in the fall spraying. Spray early enough in March that the buffalograss is still dormant. Look at the base of the plants to make sure there is no green. Treat on a day that is 50 degrees F or warmer. Rain or irrigation within 24 hours of application will reduce effectiveness.  Use a combination product such as Trimec, Weed-B-Gon or Weed-Out. Weed Free Zone is also good and will give quicker results under cool conditions.

April

Apply crabgrass preventer between April 1 and April 15, or apply preventer when the eastern redbud is in full bloom. If using a product with prodiamine (Barricade), apply two weeks earlier.  Crabgrass preventers must be watered in before they will work. Avoid using broadleaf herbicides as the buffalograss is greening up as injury can result. The buffalograss will not be killed but growth will slow making the buffalograss less competitive with weeds.

June

Fertilize with 1 lb. of nitrogen per 1,000 square feet during June. More applications will give a deeper green color, but can encourage weeds. If it is felt that a second application is needed, apply in July.

If grubs have been a problem in the past, apply a product containing imidacloprid by mid July. Imidacloprid can be applied as early as mid May if there are problems with billbugs or May beetle grubs. These products kill the grubs before they cause damage. They are effective and safe but must be watered in before they become active. Again, I would only treat if grubs have been a problem in the past. Note that the whole area may not need to be treated. The beetles that lay the eggs for the grubs are attracted to lights and moist soil and those areas are most likely to be infested.

Late-July through August

If you see grub damage, apply a grub killer. If imidacloprid has been applied or if grubs have not been a problem in the past, this should not be necessary. Grub killers must be watered in immediately.

Late October to Early November

Spray for broadleaf weeds if they are a problem. Look carefully as our winter annuals such as chickweed and henbit are small and easily overlooked. Use a product that contains 2,4-D as it increases effectiveness on dandelions. Treat on a day that is at least 50 degrees F. Rain or irrigation within 24 hours reduces effectiveness. Use the rates listed on the label for all products mentioned.

It is as simple as that!  Enjoy!

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.***

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New Weed Control Publication For Turfgrass Professionals

Posted on by jahoyle

(By Jared Hoyle, KSU Turfgrass Research and Extension)

In 2016 Dr. Aaron Patton and Daniel Weisenberger reached out to surrounding universities to collaborate on producing a multi-state Turfgrass Weed Control for Professionals Publication.  There are 11 states, including Kansas, that worked together to help produce the 2017 edition.

 

Guide provides weed identification and control information that turfgrass professionals can use to develop effective weed control programs for golf courses, athletic fields, sod farms, lawns, and other turfgrass systems. Recommendations apply to most states, with input from experts in IL, IN, IA, Kansas, KY, MI, MN, MO, NE, NY, OH, and WI.

It contains images and information for identifying 105 different weed species.

 

 

Covers herbicide selection in:

  • Nonselective herbicide/fumigants for renovation
  • Nonselective herbicides for border maintenance
  • Preemergence herbicides
  • Postemergence broadleaf herbicides
  • Postemergence grass herbicides
  • Postemergence sedge herbicides
  • PGRs for general turf
  • PGRs for putting greens
  • Herbicides labeled for putting greens (PRE and POST)

The publicationl also covers many other weed control aspects like;

  • Which herbicide works best for each weed.
  • Includes notes and comments on each herbicide.
  • Control of tough weeds.
  • Provides handy comparisons of broadleaf herbicide ingredients.
  • Covers fundamentals of how herbicides work
  • frequently asked questions.

GET YOURS TODAY! 

For an electronic download copy for 12.00 click here – https://mdc.itap.purdue.edu/item.asp?item_number=Turf-100-W#.WMFVKGVuD8s

For a hard copy delivered to your door (20.00) click here – https://mdc.itap.purdue.edu/item.asp?item_number=TURF-100#.WMFVDWVuD8u