K-State Research and Extension News
March 22, 2012
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Move Up 2012’s Crabgrass Preventer Deadline


Nothing ‘Crazy’ about These Socks


Alfalfa Weevils Spotted in Kansas






Move Up 2012’s Crabgrass Preventer Deadline

 

MANHATTAN, Kan. – When forsythia and redbuds reach full bloom, crabgrass will be sprouting soon.

 

“Generally, you get about two weeks between those events. So, since spring seems determined to get an early start this year, crabgrass is likely to germinate several weeks earlier than normal. Most Kansans should think about using April 1, not April 15, as their deadline for spreading preventer on their lawn,” said Ward Upham, horticulturist, K-State Research and Extension.

 

With few exceptions, crabgrass preventers are simple pre-emergence herbicides. They have to be in place before crabgrass seeds germinate. They require a follow-up application about eight weeks later (May 27), to pick up any late starters.

 

Once applied to the soil, though, these preventers gradually begin to lose strength. So, applying them too early can be a time and money waster, Upham said.

 

“Products vary, of course. But, most are fairly ineffective after about 60 days,” he said.

 

The major exceptions are season-long preventers: Barricade (prodiamine) and Dimension (dithiopyr). Nowadays, both are available under their trade and/or their chemical name. (Herbicide labels list the product’s active ingredients, as well as instructions for its safe use.)

 

Homeowners usually can apply Barricade in November, to provide crabgrass control the following spring. Still, Barricade’s no exception to the lawn-seeding rule:  Pre-emergence herbicides are hazardous until new turf has grown enough to merit mowing two to four times.

 

March 1 is the earliest to apply Dimension. Upham said, however, it’s the better choice in two situations:

 

  • You missed fall’s and spring’s application deadlines. Dimension is the one preventer that also can kill young crabgrass until it exceeds the two- to three-leaf stage.

 

  • You’ve seeded. Dimension is uniquely kind to young cool-season turfs. In fact, it’s safe to use two weeks after tall fescue, perennial ryegrass, or Kentucky bluegrass germinates.


 

 


 

 

Nothing ‘Crazy’ about These Socks

Photo available


TOPEKA, Kan. – If one person can make a difference, think what 209 can do?



Leah Kimzey, a high school senior from Fredonia, Kan., who often is teased about wearing what she calls “crazy socks,” now has others – make that 100s of others – doing the same.



Kimzey, is a Kansas 4-H member and member of the Kansas 4-H Youth Leadership Council, a group of 20 teen leaders charged with planning and leading opportunities for youth to grow as young leaders, practice citizenship and build community by serving their communities.



Youth Council projects include hosting Campference, a summer camp/conference for teens; the Kansas 4-H Youth Leadership Forum at Rock Springs 4-H Center (Junction City, Kan.) each November, and Citizenship in Action (CIA), a two-day conference offering opportunities for youth to learn about state government in Topeka, Kan. in February.



Though new to the planning team, Kimzey noted a full CIA schedule of caucuses, discussions about issues facing state leaders, meetings with legislators, and the absence of a citizenship project.



Since a dance is typically a favorite at 4-H events, she proposed a sock hop, with a request that the 209 delegates attending the conference donate socks as admission to the dance.



The idea proved a hit with the planning group and teens attending the conference, including some who brought packages of socks.



As a result, 740 pairs of socks plus cash donations to fund 900 meals were presented to Mark DeGroff, director of communications of the Topeka Rescue Mission, which serves residents in need. DeGroff also served as a conference presenter.



“It’s awesome,” said Kimzey, who credits the Council’s enthusiasm for the idea as a large part in the project’s success, and for giving her career goal – majoring in agri-business, leadership studies and public relations at Kansas State University – a boost of confidence.

 

                                                                       


 

 

Alfalfa Weevils Spotted in Kansas

 

MANHATTAN, Kan. – It’s not only cyclists and joggers taking advantage of recent unusually warm Kansas weather -- alfalfa weevils are rapidly developing throughout the state, according to K-State Research and Extension entomologist Jeff Whitworth.

 

Whitworth said samples he’s taken and reports from others showed the first larvae were detected the week of March 5, and with the significant warm spell Kansas has experienced since then, egg and larval development has been readily apparent.

 

“All fields we sampled this week in central Kansas had 10-30 percent of the stems infested with 1st instar larvae,” Whitworth said. “Most infested stems had multiple larvae simply because that is where the female weevil deposited a clutch of eggs last fall and now they are all hatching together.”

 

Treatment thresholds vary in alfalfa, depending upon the end use, but usually delaying application until there is one larva for every two stems (50 percent infestation) is the most effective management tactic, he said.

 

“This warm weather may condense weevil development by increasing it so quickly, so early that the infestation may not drag out over a 4- to 6-week period as it has in the past,” Whitworth said.



“We’ve been getting questions about the use of chlorpyrifos, or products containing chlorpyrifos, relative to the legality of making a second application, if needed, per cutting. This question has arisen because of the early egg hatch and the potential length of time between this and swathing, which usually doesn’t occur until at least late April.



“If you do decide a second application is necessary prior to that first cutting, make sure you consult the label of the product you intend to use to ensure it is allowed for that product. Always read the label prior to and have the label available during application.”




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K-State Research and Extension is a short name for the Kansas State University Agricultural Experiment Station and Cooperative Extension Service, a program designed to generate and distribute useful knowledge for the well-being of Kansans. Supported by county, state, federal and private funds, the program has county Extension offices, experiment fields, area Extension offices and regional research centers statewide. Its headquarters is on the K-State campus, Manhattan.

Story by: Elaine Edwards
elainee@ksu.edu
K-State Research & Extension News

Contributing writers: Mary Lou Peter, Nancy Peterson and Kathleen Ward