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Our trend of cool, wet, protracted springs in northern Illinois has certainly been put in abeyance for this year! March was several degrees colder than average (data from OHare station), and we had only 50% of normal precipitation.
However, April was warmer than average but has remained dry.
In the January through March quarter, we had exactly ZERO base 50 growing degree days (GDD50) a little different than last year I bet.
In April we jumped up to 158 GDD50 ,with most of those warm days occurring from April 19-30.
The trees are leafing out quickly (even the slower oaks), the Forsythias have bloomed, hostas are up, and the dandelions are coming on strong.
Everyone is out spraying weeds, and fertilizer + preemergence crabgrass herbicide combos are going out now on Kentucky bluegrass fairways and roughs.
I have three trials for Poa flowering (seedhead) suppression established now in the western suburbs two are at green height (Aurora and Fox Valley CCs) and the third is at fairway height (Chicago GC).
Plots were sprayed April 26 and 27.
The main treatments are Embark T & O (Lite at 1.3 fl oz/1000 ft2), Proxy (5 fl oz), Proxy + Primo (5 +1/8), and the wetting agents Cascade (4 fl oz 2x) and AquaGro L (8 fl oz + 4 floz).
The wetting agents are applied at roughly 7 day intervals.
It will be interesting to see the response this year in the heat; last year I sprayed and evaluated plots wearing a heavy jacket on most days to keep from freezing!
Based on the 50 GDD model for seed heads, we should have been spraying about 10 days earlier than I did, but there were no visible seed heads on any of the Poa when I sprayed the test plots.
Dr. Bruce Branham has tests out again this year at the U of I, and his sprays were applied 2-3 weeks earlier than mine (which makes sense since Urbana is usually a couple of weeks ahead of us weather-wise).
Also, Bruce is doing some timing studies with Proxy (as are several other researchers around the area), and there is a joint effort around the Midwest at universities to collect weather and Poa seeding data to try to re-examine the degree day model for Poa annua flowering.
Diseases
The disease focus for now continues to be Gray snow mold, especially in regard to recovery from last winters damage.
In bentgrass fairways, recovery has been slowed because of the cool, dry weather from early March through mid-April, and because of the crustiness of dead foliage in some of the harder hit turfs.
It seems to me that the Typhula fungi and other organisms rotted the leaves and some of the thatch to the point where a congealed layer of crud has sealed the soil surface much like an algal crust will do in summer.
The crust is preventing bent/Poa shoots from getting to the air and sunlight needed to grow.
I guess the best thing to do if you are still struggling with recovery is to spot aerify, slit or spike the worst patches to break the crust; some overseeding may be in order as well (get the divot crews out!).
I don’t think verticutting with standard units will help much, since the growing turf around the patches will keep the blades elevated above the tight crust that has formed.
Insects
Mound building ants (little red and black ones!) are showing up around the area already.
If you want to try the Maxforce type baits this year, now is the time to treat the mounds and colonies that are forming underground.
The idea behind these slow acting baits is to have worker ants pick up the bait and carry it down into the colony and feed it to the queen.
Once the queen dies, the colony will die out also (hopefully).
If you wait until later in the summer, colonies are much bigger and harder to control with baits (or with standard insecticides).
Drenching mounds with Dursban or other contact insecticide is still an option, but usually only serves as a temporary control near the surface.
I have also had a couple of questions/comments about springtime damage from overwintering white grubs, and the four-legged beasts that are digging them up for hors dourves.
In general, the grubs do very little damage to the turf, mainly because it is growing rapidly and making new roots now.
So, the issue is do you spray an insecticide to kill the grubs and stop the animal feeding this early in the year??? Personally, I would skip the insecticide and just fix the animal damage as it occurs.
First, the turf should heal quickly at this time of the year (barring a cold snap!).
Second, it is too early to spray longer lasting insecticides like Merit or Mach 2, which are targeted for Ataenius in July and white grubs in September.
Besides, these slow acting insecticides wont kill the grubs quickly and the stinkin’ skunks will keep feeding until the grubs pupate anyway.
Weeds
There are plenty of dandelions and other broadleaf weeds growing now, and it is a good time to spray during this warm, dry weather pattern we are having (albeit it is a little windy...)
Most herbicides work much better when applied at warmer temps, since the weed is actively growing and will uptake and translocate the a.i. more readily than when it is cold and / or cloudy.
Moss on greens continues to be a problem for many area superintendents, and is showing up quite nicely this spring.
Control strategies vary and we have seen mixed success for programs using Fe sulfate or soaps/wetting agents (eg DawnUltra).
Last fall, Dr. Frank Rossi from Cornell presented some interesting data using copper products to control moss (eg Junction = mancozeb + copper sulfate), and this approach bears further consideration.
Recently, I have seen some treatments with a new product called TerraCyte (made by the company that markets Zerotol – Biosafe Systems) which looks like it has some promise for moss control.
A number of superintendents are trying it on a limited basis this spring.
I will report back later with more info...
Your pre-emergence crabgrass herbicides should be going out about now as well for best control (soil temps in the 60s for several consecutive days).
But if you miss the window or want to spot treat the crabgrass on a post emergence basis, there are some good herbicides for that approach as well (eg quinclorac).
See the turf tip by Cella et al (1999) at:
http://www.turf.uiuc.edu/itf/publications.html
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