Weather
Temperatures are heating up over the next week with a cool front forecast for next weekend. Scattered showers are in the forecast for Thurs.
Diseases
On about Wed. last week, dollar spot showed up in Guelph. This is about a week later than normal. Our average date for it to appear in Guelph is June 5. More and more spots are appearing daily. Another disease that might become active over the next week with the high heat is anthracnose. Possible, but less likely is that summer patch symptoms may show up. This disease likes poorly drained sites. Symptoms develop in hot, rainy weather or when high temperatures follow periods of heavy rainfall. If you encounter a disease that you can’t diagnose, there is information on submitting a sample to the GTI Turf Diagnostics at the link.
As I mentioned last week, there is now a biofungicide product in the disease control arsenal for golf courses and sod farms for dollar spot, anthracnose and brown patch based on a bacteria (Bacillus subtilis strain QST713). The product is marketed under the trade name Rhapsody. Rhapsody is a preventative biofungicide and applications should begin when conditions are favourable for disease development.
Insects
Annual bluegrass weevil damage is being reported from the field. The damaging stage has been found on many golf courses now. Damage first appears as small fist sized clumps of yellowing turf on the edges of fairways and on collars. When the turf is examined, it is annual bluegrass that is dying and when you tug on it, it pulls out easily. There have also been reports of black turfgrass ataenius damage. It usually is mistaken for drought symptoms or areas where irrigation is uneven. On closer examination, the turf roots have been pruned.
The first black cutworm damage is starting to show up now. I saw the first European chafer adult on Father’s day at dusk. Japanese beetle adult flights will not be far behind. The flowering plants that signal peak egg laying of hairy chinch bug are in flower now. Some young hairy chinch bug nymphs have been reported in the Toronto area. We are probably about 3-4 weeks away from the peak damage period.
Weeds
I would say with this hot weather that we are having, the broad-leaf weed control window for Sclerotinia minor is over. The next opportunity to use this product will be in the late summer. Crabgrass has definitely germinated in most areas now. The spring annual broadleaf weeds like pineapple weed are out in full force now. There are still opportunities to use non-selective weed control actives, acetic acid and fatty acid. Acetic acid can be used as a spot treatment for weeds in lawns. The fatty acid products can only be used to control weeds in patios, sidewalks and driveways. These active ingredients are listed in the searchable pesticide database on the MOE website link and you can find out the trade names available for those active ingredients. Don’t forget the non-selective weeding tools.
General Conditions
The rain and the hot weather have produced a flush of turf growth. Most of the seedhead production has finished now. There are lots of clippings to deal with. There is also a lot of scalping injury because of the soft conditions on golf course greens after the rain. – See more at: https://lawnsavers.com/turf-hotline-2009/turfgrass-management-agriphone-for-june-23-2009.html#sthash.ZYUGDoxC.dpuf
