InteractiveTurf Newsletter newsletter@interactiveturf.com June 16, 2003 Starting to Crank Up!! Weather review: Our cooler than normal weather pattern has continued to be the big story. Temperatures for the first half of June are averaging about 5 degrees below normal. Dryer air seems to have returned with this pattern, as total precipitation for the Chicago area for June is around an inch (or less) in most areas. Of course, after the 5-7 inches of rain we received in May, we really aren’t feeling the effects of lower precipitation to this point in June.. but stay tuned! The cool air has continued to hold down the growth rates of our turfgrasses, especially creeping bents and some of the newer Kentucky bluegrasses – much to the consternation of various tournament officials and a TV commentator or two. Considering the difficult winter we experienced and the crappy weather so far this spring, all three recent tournament venues were in excellent condition, and the golf was outstanding. Congrats to Dan Sterr at Stonebridge (LPGA Kellogg-Keebler Classic), Tom Pritchard at the Glen Club (Nationwide Tour LaSalle Bank Open), and Dave Ward at Olympia Fields CC (US Open) as well as their staffs and volunteers for their major contributions to the success of these events. There is one more big time tournament to go – the Western Open here at Cog Hill July 3-6 (hopefully it won’t be hotter than normal for this one!) – stop by and see us at Golf House! Diseases: Dollar spot activity has increased over the last few days, especially in areas where daytime temperatures are climbing above 80 F. Dollar spot has been fairly active and severe for the last couple of weeks in central and western Illinois, but the cool air in northern IL has kept a lid on severe disease outbreaks. That being said, initial outbreaks have occurred over areas of Chicagoland not influenced by cooler lake air, and the dollar spot prediction model has been going off almost every day there since June 5-7 (see table below). Weather forecasts for the next few days suggest a warming trend, so initial dollar spot activity should start by the lake soon (if not already), and areas that have seen minor initial symptoms should see the disease start picking up some steam. Few other disease problems have been reported, except for some continuing basal rot anthracnose on Poa annua. We have not seen as many outbreaks of cool weather brown patch (Rhizoctonia cerealis) or yellow rings on Poa (R. zeae) like we experienced in spring of 2002. There has been some minor activity by Microdochium nivale (pink snow mold) in cool pockets on a few courses north of Chicago. In Newton, IL, (which is between Carbondale and Decatur) we have had a report of heavily matted mycelium in the rough area this past weekend. This is either Pythium or Rhizoctonia activity , indicating that warm weather pathogens could be cranking up in the southern IL, and are headed towards the central IL region. Prediction Model Summary Location Degree days (to 6/15) Prediction Model Model Start Date (Initial Report date) St. Louis 1,115 JB adult (yellow) Dollar spot Brown Patch 6/13 4/11 (4/15) 6/13 Bloomington 829 Dollar spot 5/9 (5/14) Peoria 826 Dollar spot 5/9 (5/15) Orland Park 618 Dollar spot 6/5* (6/12) Aurora 570 Dollar spot 6/7* (5/27) Frankfort 536 Dollar spot 6/5* (5/14) Naperville 529 Dollar spot 6/5* (5/26) Lemont 524 Dollar spot 6/5* N. Barrington 404 Dollar spot 6/5* (6/2) * The dollar spot prediction model also sporadically went off in early May in the Chicagoland area (which could've caused initial outbreaks), but this date marks the beginning of steady alerts and potentially more severe activity. Insects: Reports of insect activity on turfgrasses have been slow in coming as well. There has been some sporadic activity by black cutworms, and earthworm casts and ant mounds are common problems. Some superintendents who have had heavy Ataenius grub infestations in the past are thinking about putting out Merit applications in the next week or so since these grubs are normally the first to hatch and feed on the turf. If grubs aren't usually a nuisance until August then the standard July 4th Merit application date, (which isn't too far away anyway), is still advised to make sure the full grub season is covered. The yellow alert signifying first emergence of the Japanese beetle adults has gone off in St. Louis/Carbondale area (see table above). This yellow alert goes off between 1049-1180 degree days, and then 90% emergence of adults goes off between 1590-1925 degree days (a.k.a. prime time Linden/ornamental feeding time). We are still a few hundred degree days away from a yellow alert in the central region, and it will be interesting to see how JB adults emerge after this a fairly cold winter throughout the region. There are a couple of interesting notes in the latest Home Yard and Garden Pest Update (No. 8, June 10) from the University of IL. One section concerns recent increases in mosquitoes. The predominant mosquito species in spring is Aedes vexans, which breeds in low-lying areas and tends to swarm after spring rains. But this bug is not a major disease carrier and is unlikely to transmit West Nile virus. The disease vector mosquitoes are more common later in the season at higher temperatures. There is also a note about the appearance of Gypsy moth larvae, and the state’s “Slow the Spread” campaign. Certain leading edge areas of infestation of northeastern IL counties have been treated with BTK (a bacterial biocontrol agent) or pheromone flakes. More info is also available at the IL Dept of Ag website (www.agr.state.il.us). Weeds: Many broadleaf weeds are now actively growing, including thistles in unmowed “naturalized” areas. We have been battling knotweed in Kentucky bluegrass rough on the three hole course at Golf House, as well as patches of clover and black medic on our new sand greens. Questions regarding moss invasion and control techniques continue to filter in to our office. There appears to be a number of factors which lead to moss invasion on putting greens, including low mowing heights, low N fertility, low K fertility, high Ca levels or high Ca/Mg ratios, and excess moisture held in/near thatch by mini perched water table (from sand topdressing). Some success in reducing moss has been found using soaps and related products (Dawn Ultra, Terracyte), or copper hydroxide (eg Junction) or iron sulfate. Moss removal can be a slow process that requires multiple treatments to gradually control the pest while preserving the turf and promoting recovery. +++++++++++++++++++++++ Thanks for your support of this, as well as all of our research programs, Randy Kane CDGA Director of Turfgrass Programs Midwest Golf House 11855 Archer Ave Lemont, IL 60439 630-257-8126 Lee Miller CDGA Manager of Turfgrass Research Midwest Golf House 11855 Archer Ave Lemont, IL 60439 630-257-2005 x.111