Friday, June 22, 2012


Nick Christians
June 22, 2012

Here is a post from our new turf research specialist at the turf research area, Dan Strey.  He recently took Marcus Jone's place when Marcus took a job in industry.

Dan Strey
June 20, 2012

As newer turf products begin to hit the market, superintendents begin to have certain questions.  Ever since Civitas has reached the Iowa marketplace, we have been asked numerous questions regarding the product. One of which was if there are signs of tracking after application.

This week, we designed a demonstration that would determine just that.  The Civitas Fungicide was applied at a rate of 8oz. per 1,000 ft² and the Civitas Harmonizer at 0.5oz. per 1,000 ft².  It was then applied to bentgrass maintained at green height. There were five test plots that each measured 25 ft². Each plot was then walked across, using white paper towels to indicate tracking, every half hour. Three golf balls were rolled through each plot as well.

It was only a half hour after the application that we found no evidence of tracking. Hopefully, this helps some of you out there. 



Nick Christians
June 22, 2012

Here is a post from Aaron Loan of Bluegrass enterprises in Cedar Rapids.  They just started seeing the Japanese Beetles as well.  I still have not seen any here.

You can see a picture on the facebook site below:

From Aaron:

We have them at our place.  Just uploaded a pic on our facebook page:

Aaron A. Loan
Blue Grass Enterprises, Inc. 
3965 C Ave Ext.
PO Box 335
Alburnett, IA 52202
P. 319-842-2165
F. 319-842-2173

Thursday, June 21, 2012


Nick Christians
June 21, 2012

I have been watching for Japanese Beetles in Ames because we are doing some research on them this year.  I have not seen any.  Three days ago, I got a call from a former student in Chicago, Brock Bollivar, saying that they had very high populations of adults there.  Then today, I got the following two pictures from T.J. Brewer at the Burlington Bees stadium in Burlington (on the Mississippi).  They showed up this morning in high numbers.  They do seem to show up from east to west, so I'll bet we will see them in central Iowa soon.  If any of you from the eastern part of the state see them this week, let me know.  Take some pictures and I'll post them.

Pictures From T.J. Brewer.  The miserable little devils are breeding and getting ready to lay eggs.

Thursday, June 14, 2012


Nick Christians
June 14, 2012

Here is an update from answer-line person, Richard Jauron, on his nimblewill control demonstration with the herbicide Tenacity (mesotrione).  You will find posts on the application from last summer and updates during the fall of 2011 and spring of 2012 .  The following pictures are from June 2012. 

The work is going well, and he feels that he has achieved at least 75% control at this time.

Nimblewill can come back later in the season from plant parts.  It can also come back from seed.  Richard will continue to monitor this.  He also plans to keep at it until he has beat the nimblewill.

 Here are some comments from Richard.

Nimblewill is present in the center of this photograph.  Area was treated with Tenacity in summer of 2011. 

 --- Nimblewill is present in photograph, but at a reduced level.

  Overall view of the backyard.  This area contained several areas of nimblewill in 2011.  Nimblewill-infested areas were treated with Tenacity in the summer of 2011.  Seventy-five to eighty percent of the nimblewill appears to have been destroyed.  

Monday, June 11, 2012

Ascochyta Wheel Tracking Syndrome

Dave Minner, Iowa State University
Craig Longnecker, Perficut Lawn & Landscape

Summer wheeling tracking by mowers has once again been sighted in Iowa. The picture sent to me by Kreg Longnecker from Perficut on 25 May shows wheel track injury to an irrigated lawn in Des Moines. A week of extremely dry and windy conditions caused some pockets of turf wilting to occur and preceded the turf injury symptoms. There is no way of predicting the type of year we will have but late May through June is the time we usually see this disorder. The wheel tracking associated with Ascochyta or drought/heat stress is unrelated to product application by lawn care companies. Follow the links at the end of this article for previous updates and pictures related to this problem in both 2010 and 2011. We have been able to isolate the fungus Ascochyta from lawns showing symptoms of tan/bleached leaves in both wheel tracked areas and injured lawns without wheel tracks. This is important information but we are still not sure how the fungus, dry stress conditions, and tire tracking all fits together in terms of making recommendations to reduce turf injury.

What we know
  • The symptoms have been reported late May through June in 2010, 2011, and 2012. 
  • Depending on the severity of injury and post injury growing conditions, damaged areas will take from 2 to 4 weeks to recover. Recovered lawns can be reinjured throughout the summer if conditions favorable for injury reoccur. 
  • Symptoms can occur without prior wilt but usually moderate wilt precedes injury, especially wheel tracking symptoms. 
  • Symptoms are bleached tan to white upper leaves with some leaf tips collapsed (see links below for several descriptive pictures of the problem). 
  • The problem is more frequently observed in newer subdivisions where lawns are less than 10 years old. Lawns in older mature landscapes, especially with large shade trees, seldom show this problem. 
  • The problem seems to be more problematic on Kentucky bluegrass, moderate on perennial ryegrass, and seldom occurs on tall fescue. 
  • The symptoms of wheel tire streaking associated with Ascochyta or drought/heat stress should not be confused with fertilizer burn or pesticide phytotoxicity.  

What we don’t know
  • There is a lot we don’t know about this disorder. Here are some of my observations and internal questions that I still struggle with. You can help me by sending pictures, information and opinions describing this problem. My phone and email contact is at the end of the article. 
  • In most cases the best looking lawns in the neighborhood seem to express the most severe injury. Lawns with automatic irrigation and higher fertility may express more injury. 
  • Iowa sod produces produce excellent quality sod, however many lawns in new subdivisions have been sodded on very poor quality subsoil using newer varieties of Kentucky bluegrass. Your comments related to the role that sod, age of lawn, soil quality, and grass variety play is needed. 
  • While we have isolated Ascochyta from injured plants we are still trying to determine if the problem is more related to the fungus or more associated to a direct injury caused by wheel stress on wilted turf. You can help by sending samples to the ISU Plant and Insect Diagnostic Clinic to confirm presence or absence of Ascochyta when these symptoms are observed. The cost for disease identification is $20. 

Plant and Insect Diagnostic Clinic
327 Bessey Hall
Iowa State University
Ames, IA 50011-3140 USA
Phone 515-294-0581

Recommendations at this time
  • The recommendations are a work in progress since research information is lacking on Ascochyta and wheel tracking. 
  • Mow taller to reduce wilt stress and less frequent to reduce the number of events when injury could occur.
  • Fungicides are not recommended at this time because of the uncertain role that Ascochyta plays in the disorder and the unpredictability of disease occurrence. We are however making preventative fungicide applications from late May through June 2012 in areas where the problem repeatedly occurs to help us determine the role that Ascochyta plays in wheel tracking.

David D. Minner, Professor
Extension Turfgrass Specialist
Horticulture Department
Ames, IA 50011
(o) 515.294.5726
(c) 515.231.1741
(f) 515.294.0730