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Weather Update
Once the last hot spell of summer left us around labor day, there hasn't been much pest activity noted in Northern Illinois.
The weather has been cool and dry for the most part, which keeps the lid on most autumn diseases.
I have had a few reports of grub damage in untreated areas, and a few reports of animals digging for grubs (mostly not finding any).
Diseases
I expect that our problems with dollar spot will continue, especially if/when warmer and more humid air filters back into the area.
I have a dollar spot control trial ongoing at the Cantigny experimental green, and the disease is still active, although obviously slowing down.
I did have to spray fungicide on my "untreated controls" because dollar spot was consuming over 30% of the surface area.
I have had only a couple of new reports of Gray Leaf Spot on perennial ryegrass, and I suspect that disease activity will slow down more as we go into October.
If we get into a wetter and cooler weather pattern over the next few weeks, watch out for early Pink Snow Mold symptoms (=Microdochium patch = Fusarium patch).
This fungus often attacks Poa annua more readily than bentgrass, and may cause a small copper colored patch on either bent or Poa; and no, it is not "copper spot".
Heavy infections in fall or spring can lead to streaking of the patch symptoms and this can be confused with cool weather Pythium.
Symptoms can streak or spread rapidly because the fungus makes large amounts of conidia (spores) which can move in water films or on mowers, shoes, etc.
Weeds
Autumn is the best time of year to aerify and overseed any stressed out areas (like your greens, tees, and fairways), and to get construction or renovation projects done for next season.
I participated in an interesting renovation project with Scott Witte and his assistant Erick at Cantigny -- we killed off and reseeded the variety trial and other parts of the green.
Killed would be the operative word, since we used Basamid to take out the existing grass.
There was some concern that the Basamid may not work adequately on a tight, greens height turf, so we went to a little extra work to try to increase the kill rate.
First, we (mostly Scott) ran a Ren-O-Thin verticut/flail machine over the turf a couple of times to make some nice grooves.
Next we drop-spread the Basamid crystals at about 375 lbs per acre; it was a little windy but the product went down pretty well.
The third step was an intensive core aerification with a Greens-aire.
The plugs were left on the surface to dry while we went for lunch (I bought!).
After lunch, Scott went over the green with a power broom to break-up the plugs and spread the sand around, while Erick and I raked out some of the fluff that was left over.
Next, Scott ran over the whole area with his riding tennis court roller, which looks like a miniature steam-roller.
The purpose of all of this soil work is to get the crystals down in the canopy and then seal up the surface with soil/sand/organic matter (remember we put the Basamid on before the aerification!).
Basamid releases some toxic organic cyano gases when it dissolves in water, so you need a soil and water seal on top of it to keep the gas from escaping too fast.
Following a last minute light topdressing with straight sand, we turned on the irrigation to dissolve the crystals and release the gas.
Scott ran some light frequent irrigation cycles the next couple of days to try to keep the water seal active over the Basamid (plus it rained one night).
When I stopped by about 5 days after the Basamid application, the treated area was dead as a door-nail; of course, so were a few areas where the Basamid got out of bounds (across some plywood boards we used on the perimeter).
A few days after the initial Basamid treatment, Scott cleaned up and dragged-in the remaining topdressing, and the green was ready to seed within a week.
I think Basamid has a lot of potential to use for renovation projects on golf courses when you want to kill the existing turf and the weed seeds (eg Poa annua), but you don't want to rebuild or otherwise change the rootzone.
Hopefully, I can get a few pictures of the project posted on the web so you can see how it worked out.
Thanks to Bruce Branham at the U of I for his helpful suggestions, and for "loaning" to us 30 lbs of product!
Be sure to check out the U of I TURF website for more information, turf tips etc. and the U of I Home, Yard and Garden newsletter.
Please respond with your observations to newsletter@interactiveturf.com.
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