Whats going on in my lawn

August 1, 2018

Many questions have come in over the past couple of weeks about what is going on in people's yards. Many of our previous blogs have covered these topics, so here are links to some of the issues in lawns.  The first issue is due to the wet state to the growing season in some of the state pre-emergence herbicides have not held up as long as typical, also know that applying a crabgrass preventer now will not help. There are some post-emergence herbicides available, but the crabgrass is very mature right now and will take a few applications. If you do have crabgrass please realize that it will die with the first frost, so if you can hang on a while longer it will die in the coming months.  Windmill grass and bremudagrass are also growing with crabgrass, check out this blog on how to identify these warm-season weeds. There are also numerous other weeds that are growing right now, including quackgrass and thistles. Quackgrass is a grassy perennial, and now is a good time to start to eliminate it so you can reseed that area in the fall. Non-selective herbicides work best to try to eliminate quackgrass, and because of the long rhizomes it may take a couple applications to control this grassy weed.

Another issue in many parts of Iowa is a lack of water. Turfgrass needs about an inch of water per week to sustain active growth. Here is a blog from last year on drought and if your yard is dead. Along with drought are several diseases including brown patch, pythium, and summer patch just to name a few of the more prevalent diseases.


Remember that grub damage will start to show up in the next couple of weeks, so keep an eye out for that. If the grass has roots that are gone and the turf just pulls up by the handful it is grub damage. Typically the grubs need to be over 10 per square foot to cause damage.

Good luck and hang in there, better weather is coming for lawns this fall hopefully.


Adam Thoms Assistant Professor

Adam Thoms, Ph.D. - Assistant Professor specializing in Commercial Turfgrass Management, Iowa State University, Department of Horticulture, Ames, IA. Dr. Thoms received his B.S. from Iowa State University, and both his M.S. and Ph.D. in Plant Sciences and Plants, Soils, and Insec...