Thanks for your continued support of the Michigan Turfgrass Foundation. The mission of the Michigan Turfgrass Foundation is to support the research, teaching, and extension programs at Michigan State University. If you are not a member and are interested in joining the MTF please Join Us. Another avenue to support the MTF and MSU Turf Team is to participate in bidding or spreading the word of our current TeeTimes4Turf auction, currently over 117 golf courses are available via an on-line auction at www.teetimes4turf.com. The auction ends on Sunday, May 14 at 7 p.m.

Broadleaf Weeds Flowering

In the last week, dandelions have been lighting up the landscape with their brilliant yellow flowers. In most areas, the first flush of dandelion flowers has come and gone and now the puff ball stage is in full effect. According to Michigan State University Extension, applying a herbicide at the puff-ball stage can be very effective as this is the time the dandelion is at its weakest because it has just spent all that energy pushing out flowers. Applications prior to puff-ball stage can be effective at burning down the rosette and preventing puff-balls but keep in mind if you really want to get ‘em, schedule a fall application. 

In addition to dandelions, many other broadleaf weeds are flowering in turf right now. Common chickweed, henbit, shepherd’s purse, yellow rocket, corn speedwell, wild violet and ground ivy are all flowering. All but wild violet and ground ivy are winter annuals. The life cycle of a winter annual is they germinate in the fall, overwinter, and then flower and produce seed in the spring. After flowering in the spring, winter annuals are usually only two to three weeks from dying. If you apply herbicides now, they will be dead and gone in two to three weeks and if you do nothing, they will be dead and gone in two to three weeks. Get it?

Similar to the strategy of controlling dandelions, there are some very tough to control weeds that are also flowering right now.  Ground ivy (AKA Creeping Charlie), wild violet, and several speedwells (Germander and Creeping) are actively flowering.  The flowering period is the best opportunity to kill them until fall arrives.  The typical broadleaf combination herbicide containing 2,4-D provides fair control at flowering but if you can find combination herbicides with the active ingredients quinclorac, triclopyr, fluroxypyr, or carfentrazone you should achieve better than fair control.   

Dr. Frank’s work is funded in part by MSU’s AgBioResearch.

This article was published by Michigan State University Extension. For more information, visit http://www.msue.msu.edu. To have a digest of information delivered straight to your email inbox, visit http://www.msue.msu.edu/newsletters. To contact an expert in your area, visit http://expert.msue.msu.edu, or call 888-MSUE4MI (888-678-3464).