Kansas State University

search

K-State Turfgrass

Month: March 2017

Kansas State University earns 2016 Tree Campus USA Recognition

Who are the future leaders in the Kansas green industries? Our K-State grads! Why are they so amazing? These students have excellent opportunities to engage in hands-on, practical learning.

As one piece of that, K-State was recently named a Tree Campus USA for the third year in a row. Congratulations to Dr. Cathie Lavis for leading the efforts, and kudos to the whole team.

More details are available in this article from K-State Communications:

http://www.k-state.edu/today/announcement.php?id=33231

As another benefit, ALL K-State students, faculty, staff, and visitors get to enjoy our beautiful campus.

 

Methods of Predicting Crabgrass Emergence

(By Jared Hoyle, KSU Turfgrass Research and Extension)

This morning when I cranked my truck up and headed to the office it was 25 deg F.  Just a couple days ago it snowed.  Just before that it was 80 deg F.  What is going on with the weather? (Every time I make that statement, someone says “Welcome to Kansas!”) With the fluctuating weather and temperatures I get the question “What date do I need to put my preemerge herbicide out on?”

Well this is a trick question because there is no correct answer for it.  Here are some of my thoughts on preemerge timing.

As soon as that first warm front comes through everyone gets excited and ready to work in their lawn.  I have even heard the comment that spring and summer are going to come early this year.  Are they right?  I don’t know but it is something to think about.

But as soon as we get excited about the warm weather we have another cold snap.  So we got all excited and talked about weeds germinating early and needing to get out our preemergence herbicides because the forsythias are blooming. But what happens when it gets cold?  Any crabgrass that “might” have germinated is now dead because of the cold temperatures. So this brings up a lot of discussion between myself and some colleges. Here are just some of the questions we are asked and a couple of comments.

Why do we recommend around April 15th for most of Kansas to put out a preemerge in our lawns?

– April 15th is about the time that we have our “last” frost/freeze. (This also shifts to April 30th in Western/North Western KS and to April 1 in Eastern/South Eastern KS.) This goes along with our concept that I was talking about before.  Even though it may be getting warm we are still might have a cold snap that would end up killing the crabgrass if it emerged. This is the same concept of why we don’t plant crops until after this date as well.  (Something I don’t know anything about but that is what I figure…..)

Should we use soil temperature at 1″ to predict when to put out preemergent herbicide applications?

-Soil temperatures are a great way of determining when to apply your preemerge herbicide.  Scientists say when soils reach a daily average of 55 deg F for about 5 days at a 1″ soil depth then it is time to put out your preemerge.  Well say you go out and measure your soil temperature at 1″  you are not going to get a daily average, you are getting a single point in time.  Does that really represent what is going on?  What if you are maintaining many different properties.  It is not practical to obtain that information.  Good news is that KSU has a website (http://mesonet.k-state.edu) that you can click your closest weather station and get daily maximum and minimum soil temperatures where you can then calculate a daily average.  Bad news it only give you a 2″ or a 4″ soil temperature.  But using the 2″ soil temperatures are going to give you a better idea of the daily averages then going and taking one measurement.

The forsythias are blooming but my redbuds aren’t. Do I still put my preemergent herbicide out?

– This is called phenology – the study of cyclic and seasonal natural phenomena, especially in relationship to climate, plant and animal life.  Many people believe that when the forsythias are blooming then crabgrass is germinating.  That is not 100% true.  When forsythias are in full bloom then we need to be getting “ready” to get our preemerge applied.  Even though we see that this is a good indicator, Dr. Fry and others reported in a study that ornamental plant flowering is not always a good way to predict crabgrass germination and emergence. (Fry, J., S. Rodie, R. Gaussoin, S. Wiest, W. Upham, and A.Zuk. 2001. Using flowering ornamentals to guide application of preemergence herbicides in the Midwestern U.S. International Turfgrass Soc. Res. J. 9:1009-1012.) There are some things to consider when utilizing phenology for crabgrass germination and emergence.  Not all forsythias will bloom at the same time.  It determines where that plant is located in the landscape.  There are micro climates in the landscape.  Think about plants located in roadway medians.  They are typically warmer due to cars and the concrete and asphalt in close proximity.  The same thing goes with crabgrass germination.  Crabgrass will germinated sooner in areas that are warmer, for example (next to sidewalks, bare ground, etc.).

Crabgrass emerging in bare ground earlier than turf

I have heard about growing degree days to predict crabgrass germination. What is that?

– Growing degree days (GDD) use air temperatures instead of soil temperatures within a formula to get a cumulative number of growing degree days.  Using base 50 deg F, once you get to about 200 GDD then crabgrass will start to germinate.  Don’t want to calculate GDDs, don’t worry there is a website that will do it for you. http://www.gddtracker.net  Just enter your area code and click on crabgrass germination on the right side and it will give you the total GDD. It will also show you a prediction for the next couple of days too. GDD do not go backwards, they only accumulate.

So to put this all in perspective using the prediction methods mentioned above this is what we got;

Today is March 14th so using the calendar model for Manhattan we would not put our preemerge out until closer to April 15th for Manhattan.

Using the 2″ soil temperature method because that is what is available to us our daily average soil temperatures (Deg F) have been;

9-Mar 47.6
10-Mar 45.4
11-Mar 43.65
12-Mar 41.15
13-Mar 39.65

With this method we would assume the 1″ soil temperature is higher but we are not to the 55 deg F mark yet. So we are getting close to putting out our preemerge herbicide.

In my back yard my forsythias are blooming.  So that means if I am using the phenology method I need to be getting ready to apply my preemergence.

Lastly, using the GDD model we are at 85 GDD. So I still have some time but getting close.  Remember though that you can get more than one GGD in one calendar day and if I look at the future (prediction on the GDD Tracker website) on March 20th Manhattan will be at 111 GDD. So just in 6 days we would have gained 26 GDD.

Now these rules, concepts, ideas are not bullet proof but it is something to think about when planning your lawn care program.  There is not magic date for anything that you do to you lawn.  You need to make sure you keep up with the temperatures, soil temperatures, precipitation, etc.  The more you know what is going on with your turfgrass the better you will be able to predict crabgrass preemergent applications.  Use more than one method.  This is going to give you the best idea of what to do!

Now by this weekend we are going to get a little warmer but again looking at the 10 day forecast it might get cold again…. Just something to think about.  I hope this got you thinking as a turfgrass manager and how this is going to help you choose products if you are going to have to get applications out earlier or even later after crabgrass has emerged.

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

(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.***

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

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

What have you been up to? – Undergraduate Research Projects

(By Jared Hoyle, KSU Turfgrass Research and Extension)

As the temperatures start getting warmer, friends and neighbors start getting out more.  So when I run into them, the first question I get is “What have you been up to?”.  Many times people think winter is slow because the grass is not growing but actually during the winter is when we try and get a lot of things done that we don’t have time to get to in the warmer parts of the year.  But one thing that we have been up to is undergraduate research projects.

In the fall of 2016 I had three students come to my office interested in conducting an undergraduate research project.  I told them that the purposes of an undergraduate research projects are; 1. Answer a question for an issue that turfgrass managers face, 2. Learn the process to conduct research and, 3. Relate your research to more than just the turfgrass manager but have a social impact.  All three of them agreed then we started brainstorming and came up with three projects.

Undergraduate Research Project #1 – Student – Peyton South

The Effect of Human Insect Repellents on Turfgrass Growth and Recovery

Ever seen this before? https://www.extension.iastate.edu/turfgrass/blog/dr-nick-christians/mosquito-spray-can-kill-grass

That is what bug spray can do to your turf.  Peyton wanted to look into it more and see if there are differences in not only the bug sprays but if there is recovery. He is currently taking data and we will get that information out there once the project is complete.  Here are some pictures of the project.

 

Undergraduate Research Project #2 – Student – Dani McFadden

Will Turfgrass Colorants Blemish Clothing?

Dani’s research project was inspired by a question I got from in education event this past year. There has been lots of research on turfgrass colorants and how long they last but what will it do to the clothing of the athletes if they fall.  So Dani went out and applied a variety of different turfgrass colorants, pulled clothing across the colorants (after the recommended drying time) and then analyzed how much colorant blemish the clothing. Once her project is complete then we will be able to determine which products to recommend to athletic field managers so they can rest assure they won’t have any phone calls about stained clothing.

 

Undergraduate Research Project #3 – Student – Gage Knudson

Prediction of baseball on-base percentage due to infield mowing height

Sometimes there is only a spit second at first base between a baseball batter and the throw at shortstop to determine if the runner is out or safe.  One component of that split second is how fast the baseball moves through the infield.  Holding all other factors constant, Gage manipulated mowing height of a simulated baseball infield to determine the speed of a ground ball hit to the shortstop.  Then he can predict the out percentage at first base.  Gage’s interest in this project not only helps field managers with maintenance of the field but shows how important it is for the coach of baseball team to communicate with the grounds manager.  To simulate a constant speed he used a pitching machine that was aimed at the infield.  Believe it or not that one slit second can be influenced just by the mowing height of the infield.

Turfgrass Care for Homeowners on the K-State Radio Network

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Just recently I was invited to speak with Eric Atkinson, host of Agriculture Today a daily program distributed to radio stations throughout the state. It features K-State agricultural specialists and other experts examining agricultural issues facing Kansas and the nation. I spoke with Eric about some issues that Kansas homeowners might be facing with their lawns and a couple things that homeowners shouldn’t worry about this year.

Click on the link below and hear more about;

  • possible winter injury
  • fertility
  • weed control
  • and more!

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

Preemergence Weed Control in Bentgrass Putting Greens

(By Jared Hoyle, KSU Turfgrass Research and Extension)

In the previous post about preemerge herbicides there is a table of many preemergence herbicides that available for professional turfgrass managers.  But when we start talking bout preemerge herbicides that we can use on bentgrass putting greens the list gets really short.  There are not many options out there for PREs on creeping bentgrass putting greens due to the injury they can cause to the putting surface.

Every golf course superintendent knows that one of the main priorities on the golf course is the putting greens. Therefore, weed control on the putting greens is a priority as well.  So lets just to go over some of the PREs that are labeled for creeping bentgrass putting greens and I will also mention one comment about each.

  • bensulide (Bensumec 4FL, Pre-San 12.5G, Weedgrass Preventer) – With this product you are not able to reseed for 4 months and do not use on greens that have more than 50% annual bluegrass.
  • bensulide +oxadiazon (goosegrass/crabgrass control) – To prevent injury apply two half rate treatments 10-14 days apart.
  • dithiopyr (Fertilizers w/ dithiopyr) – Older bentgrass varieties may result in undesirable injury.
  • siduron (Tuperson) – May be applied at time of seeding or to established creeping bentgrass for crabgrass control and bermudagrass suppression.

Also, you can see the list is a lot shorter then the list in the previous post but that is why managing bentgrass is so difficult.  Turfgrass managers must to do whatever they can to have a healthy growing creeping bentgrass system to prevent weeds coming in because once they are there, there isn’t many options to git ride of them.

Information in the previous list was acquired from “Turfgrass Weed Control for Professionals” by A. Patton and D. Weisenberger, Purdue University (and 11 collaborating states including Kansas). For more information about purchasing this publication see;

https://blogs.k-state.edu/turf/new-weed-control-publication-for-turfgrass-professionals/ 

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

“An ounce of prevention is worth a pound of cure.” by Benjamin Franklin – (That Goes for Preemergence Herbicides Too!)

(By Jared Hoyle, KSU Turfgrass Research and Extension)

“An ounce of prevention is worth a pound of cure” – Benjamin Franklin

When I start talking about pre-emergent herbicides this quote from Benjamin Franklin always pops in my head.  Although, Ben was giving fire-fighting advice to Philadelphians because fires were a dangerous threat at that time it does apply to many things we are dealing with right now, including spreading wild fires. (I won’t comment on that because I have no idea how to manage wild fires.) But I will talk about Pre-remergent herbicides.

Pre-emergent (PRE) herbicides prevent summer annual weed (For Example, crabgrass, goosegrass, annual sedges, and spurge) seeds from developing into mature plants.  The reason we use PRE herbicides for summer annual weed control is because these summer annuals come back every year from seeds.  So if we can stop the seed from growing then we don’t have to deal with the weeds later in the season.

For all that don’t know how a PRE herbicide works here is a very short explanation.  They do not keep the seed from germinating but kill the young germinating plant.  With few exceptions they have no effect on existing plants, so they must be applied before germination.

But like in everything in life there is an exception.  Dithiopyr can kill crabgrass as long as it is young (two- to three-leaf stage, see photo below of three leaf crabgrass) and still have some residual for continued PRE activity. It doesn’t last as long as some of the other PRE herbicides but there is flexibility if you miss your window of opportunity to apply.

Slide1

So when do I put out the PRE application for summer annual weed control? Well, it depends on many things.  What summer annuals you have? Where are you located in Kansas?  Many times turfgrass managers center their PRE applications around crabgrass germination.  Crabgrass “typically” begins to germinate around May 1 or a little later in KS. April 15 is a good target date for applying a PRE because it gives active ingredients time to evenly disperse in the soil before crabgrass germination starts. The April 15 target works well for most of the state, but for southeast Kansas April 1 is more appropriate, and for northwest Kansas May 1 is best.  Additionally, weather varies from one spring to the next (As we can see this year where it is getting warmer earlier!), and with it the timing of crabgrass germination. Some turfgrass managers base their PRE application around the bloom of the Redbuds but other ways can be used as well.  Crabgrass germinates when the soil at approximately 1 cm deep reaches 55° F.  So watch your soil temperatures to see when the soil consistently reaches 55° F. Here is a great website that will give you soil temperatures for your area.

http://mesonet.k-state.edu/weather/historical/

PRE herbicides do not last forever once applied to the soil. Microorganisms and natural processes begin to gradually break them down soon after they are applied. If some products are applied too early, they may have lost much of their strength by the time they are needed.  Additionally, PRE herbicides have different half-life, Koc, water solubility, and vapor pressure. This can determine how fast microbial, chemical and physical decay occurs along with infiltration, volatilization, leaching, and run-off.

Slide6

Therefore, not all PRE herbicides are created equal.   Here is a list of PRE herbicides, the weeds they target and some concerns that you might want to know before applying.

Active Ingredient Weeds Controlled Concerns or Comments
benefin summer annual grasses, annual bluegrass, some-small seeded broadleaves Do not use on golf course greens.
prodiamine summer annual grasses, annual bluegrass, henbit, chickweed, spurge, some-small seeded broadleaves Only apply to well established turfgrass.
bensulide annual grasses, some broad-leaves Do not use on putting greens composed of  > 50% Poa annua.
florasulam broadleaves, dandelion, prickly lettuce, clover Packaged with Dimension 2EW, florasulam great cool temperature activity, Prevents flowering in some broadleaves (dandelions).
dithiopyr summer annual grasses, annual bluegrass, yellow-woodsorrel, some small-seeded broadleaves PRE and early post-emergence activity on crabgrass.
isoxaben broadleaves such as chickweed, henbit, spurge, plantain, others Tank-mix with a grass herbicide for broader spectrum.
pronamide annual bluegrass, perennial ryegrass, other grassy & broadleaf weeds. Do not use on cool-season turf. Restricted use pesticide.
pendimethalin summer annual grasses, annual bluegrass, yellow-woodsorrel, some small-seeded broadleaves Not recommended for turf severely thinned due to winter stress.  Split applications can be made for extended control.
metolachlor annual bluegrass, crabgrass, sedges Do not use on cool-season turf.
simazine summer annual grasses, annual bluegrass, henbit, chickweed, spurge, some-small seeded broadleaves Do not use on cool-season turf.
ethofumesate annual bluegrass, annual grasses, some annual broadleaves See label for reducing annual bluegrass in cool-season turf.
oxadiazon summer annual grasses includinggoosegrass, annual bluegrass, some-small seeded broadleaves Ronstar G and Oxadiazon 2G are only formulations labeled for use on cool-season turf.
indaziflam annual grassy and broadleaf weeds in turf Do not use on cool-season turf.
oryzalin summer annual grasses, annual bluegrass, some-small seeded broadleaves Do not use on cool-season turf except tall fescue.
dimethenamid bittercress, crabgrass, goosegrass, purslane, sedges, spurge On golf courses: Can be used on cool- and warm-season.  Other turf areas: Warm-season only.
siduron crabgrass, bermudagrass (suppression) Does not control goosegrass or annual bluegrass.

Information in this table was acquired from “Turfgrass Weed Control for Professionals” by A. Patton and D. Weisenberger, Purdue University (and 11 collaborating states including Kansas). For more information about purchasing this publication see;

https://blogs.k-state.edu/turf/new-weed-control-publication-for-turfgrass-professionals/ 

 

***There are many combination PRE herbicides that combine these active ingredients with each other and with other POST-emergent herbicides***

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

Knotweed – Last year it was April, Now its February!

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Last year I did one of my first Turfgrass Selfie Series on knotweed control in April.  The knotweed had germinated and started to mature.  Just a couple weeks ago I was walking into my office and I saw knotweed already germinating.  (See picture below – Photo taken Feb. 22, 2017)

So needless to say.  If you didn’t get your preemerge out and you have a history of knotweed it is time to go out and attack the knotweed and other broadleaf weeds you have lingering around.  These weeds are easier to control now when they are young compared to when they get mature.

Below is the Knotweed Control Turfgrass Selfie Series Video I did last year but here are the take home messages;

  • Early germinating summer annual
  • Likes compacted soils/flooded areas
  • 2,4-D = fair control
  • 2,4-D + triclopyr or dicamba = excellent control
  • metsulfuron can be used in warm-season turf
  • PRE applications must be done in the Fall

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 Cool-Season Grasses

(By Jared Hoyle; KSU Turfgrass Research and Extension)

Where did winter go? Or was it even here?  Depending on where you lived in Kansas you could have had a cold winter, warm winter, or a mild winter… But now it is getting warm and quick.  So before we get left behind lets prepare your cool-season turf for the year.

Homeowner Do-It-Yourself Lawn Calendar for Cool-Season Grasses
The following suggestions are for cool-season grasses such as Kentucky bluegrass or tall fescue. Zoysiagrass, bermudagrass, and buffalograss are warm-season grasses and require a different maintenance regime.

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

DSCN0010April 
Apply crabgrass preventer (Or maybe even a little bit sooner this year) when redbud trees are in full bloom, usually in April. The preventer needs to be watered in before it will start to work. One-quarter inch of water will be enough to water in any of the products mentioned in this calendar.  Remember that a good, thick lawn is the best weed prevention and may be all that is needed.

May
Fertilize with a slow-release fertilizer if you water your lawn or if you receive enough rainfall that your turf normally doesn’t go drought-dormant during the summer. If there are broadleaf weeds, spot treat with a spray or use a fertilizer that includes a weed killer. Rain or irrigation within 24 hours of application will reduce effectiveness of the weed killer, but the fertilizer needs to be watered in. If you are using a product that has both fertilizer and weed killer, wait 24 hours after application before watering in.

June through Mid-July
Apply second round of crabgrass preventer by June 15 – unless you have used Dimension (dithiopyr) or Barricade (prodiamine) for the April application. These two products normally provide season-long control with a single application. Remember to water it in. If grubs have been a problem in the past, apply a product containing imidacloprid during the first half of July. This works to prevent grub damage. It must be watered in before it becomes active.

IMG_0563Late-July through August
If you see grub damage, apply a grub killer that contains Dylox. Imidacloprid is effective against young grubs and may not be effective on late instar grubs. The grub killer containing Dylox must be watered in within 24 hours or effectiveness drops.

September
Fertilize around Labor Day. This is the most important fertilization of the year. Water in the fertilizer.

November
Fertilize. This fertilizer is taken up by the roots but is not used until the following spring. Water in fertilizer. Spray for broadleaf weeds even if they are small. Broadleaf weeds are much easier to control in the fall than in the spring. Spray on a day that is at least 50 degrees. Rain or irrigate within 24 hours reduces effectiveness. Use label rates for all products!

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 Weed Control Publication For Turfgrass Professionals

(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