|
Here is your first IPM update for August 2000, covering pest problems for Illinois golf courses and sod producers.
Needless to say, the weather has been very tame "heat-wise" and more than adequate rain has been falling over the state for the last few days.
While visiting with a few central Illinois superintendents at last week's, I was informed that I am propagating spurious weather data for down state, especially in regards to number of days with high temps greater than 90 degrees.
I am sticking to my guns however - Bloomington has now had (officially?) 16 days with daily high temperature greater than 90 F, although Springfield and Champaign official weather sites report zero days with temps > 90.
How can this be? Maybe Bloomington recording station is in a real hot spot!
You can easily get historical weather data from the Web BTW.
Weather Update
The national weather service predicts that the first day of summer for Chicago will occur on or about August 10, but don't hold your breath (!).
This summer = piece of cake/can of corn?
Diseases
Pathologists in the eastern seaboard states have started to find early evidence that Gray Leaf Spot on perennial ryegrass is becoming active, and could be a serious problem through late summer and early fall.
We have seen very early and light damage from GLS in central Illinois on a couple of sites, so the pathogen is becoming active in Illinois as well.
In early stages, GLS is hard to identify from symptoms alone.
Infected plants often have small purple "leaf spot" lesions, and as the disease progresses infected leaves will often turn yellow, wilt, twist and curl, then turn brown or reddish brown.
Severe Helminthosporium-type leaf spots can cause similar symptoms, but generally will not cause large scale epidemics and turf loss like GLS.
If you have ryegrass and intend to spray preventatively for GLS, I guess NOW would be a good time to get the application out?
Insects
Evidence of activity of cutworms and sod webworms continues to come in to my office - keep scouting for these pests on greens, tees, and fairways.
I have a few reports of Gypsy moth sightings on golf courses, and Japanese beetle adult feeding continues to affect scattered sites.
If you don't have your late-summer grub control materials applied yet, it is getting to be time to do that as well.
Check out for more info on bugs of turf and ornamentals.
Weeds
Frequent rains and warm weather will continue to cause algae to be a problem on poorly drained sites with thinning turf.
It has been a very good summer for crabgrass and a number of broadleaf weeds such as clover and plantain.
I am still hearing complaints about Poa annua that is continuing to produce seed through the summer; I suspect this is because the plants are under minimal stress and are enjoying the mild summer?
UIUC FIELD DAY
Field day this year was Thursday, August 3rd at the Landscape Horticulture Research Center in Urbana.
It was a cloudy and cool morning, following a hot and humid day on Wednesday (must have been 89 degrees!) and overnight thundershowers.
The hot and humid weather was very evident because of the fabulous disease pressure and symptoms that were visible on the plots for Field Day :-) There were classic Rhizoctonia Brown Patch symptoms on the colonial bents in the fairway height variety trial, and some very active Pythium blight was observed on some lawn height perennial ryegrass areas.
We also saw red thread and pink patch (mostly on ryegrass), and some heavy duty rust infections on Kentucky bluegrass.
Needless to say, there was a ton of dollar spot on the bentgrass green height plot, as well as in the longer grasses.
There are some very interesting and unique research projects underway on campus as well.
For example, Luke Cella has developed a machine to measure the quality of a golf ball's "lie" on different types of fairways, and he is studying how grass species and management practices contribute to how "good" a lie you will get when you hit it straight down the middle.
(Luke is thinking of patenting the "Cellameter" but isn't sure he wants the same notoriety as mister Stimpson.)
Sam Schmitz is doing an interesting study of divot repair conditions, which will help people choose the best backfill material and seeding rates to speed recovery.
Joe Meyer (poa control), Brian Horgan (denitrification losses), and Darin Lickfeldt (genetic diversity of blends) also gave excellent presentations of their graduate research - look for results at the NCTE or in turf publications.
Field day included a morning trade show, a great lunch, an equipment demonstration and afternoon workshops.
All in all, it was another excellent turf field day, thanks to the efforts of Tom Voigt, Bruce Branham, Hank Wilkinson, Tom Fermanian, Andy Hamblin, and all the students and staff.
|
