Weather
The heat wave is forecast to continue until Thurs. Aug. 20th. During that time there are risks of thurnderstorms each day and high humidex readings. Night temperatures will stay high for Mon. night and Tues. night. These next couple of days there will be a high risk of the hot weather diseases Pythium blight and brown patch occurring. If you have thunder storms roll through, this will add to the disease risk by saturating the soils and increasing the relative humidity. If you have had a history of these two diseases on certain greens on your golf course, it would be wise to treat preventatively for them late last week. The threat of these two diseases occurring will be over by Wed. when the cold front is forecast to pass through.
Diseases
Dollar spot was rampant last week on non-treated areas of golf courses. It has slowed down very briefly over the last couple of days with the very high temperatures. Look for a surge of dollar spot activity again when the temperatures cool and we get heavy dews again. There is also a high risk of summer patch developing with the saturated soils and hot temperatures that will result from thunderstorms. There were several cases of summer patch diagnosed last week at GTI Turf Diagnostics. Anthracnose basal rot could also be developing. If you are observing symptoms that resemble yellow patch now that the temperatures are hot, it is possible that it is Waitea patch. There have been several confirmed cases of Waitea patch in Ontario this summer so far. Rust pressure is still very intense on home lawns, sod farms and sports fields. Usually a light application of nitrogen will help the turf grow out of the rust symptoms.
This week again there are still abiotic symptoms showing up such as waterlogged, thinning turf and scalped turf. Moss and algae continue to be a problem as well as black layer. Once the current wave of hot weather is over, it will be a good idea to aerate to help the saturated soils dry out and to promote some new root development. 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.
Insects
There have been lots of reports of chinch bug activity over the last week. I have had a few calls about hairy chinch bug control with the cosmetic pesticide ban. There is no product that can be used to treat chinch bugs. Some suppliers are working with some lawn care companies to experiment with nematodes to control chinch bugs. I have not heard yet if they are having any good results with nematodes. We are expecting to see some European crane flies emerging in the next week or two and I will keep you posted when that occurs.
There are still a few cutworms lingering and doing some damage. Both European chafer and Japanese beetle grub development seems to be a couple of weeks behind this year. They are only in the very early first instar stage at the moment in the Guelph area. I have had a few phone calls from various areas of the province looking for advice on timing for nematode treatments against European chafer grubs. In most areas, the last two weeks in August will probably be the ideal time for nematode treatments. They could extend into the first week in September as well. On that note, I am still looking for a European chafer grub infested large residential/estate property for a grub trial with some alternative products within one to one and a half hours of Guelph. A golf course might work, but it would have to be an out of play area. We need an area that is roughly 15x15m2. If you have a client with such a property or you have an area on your golf course could you please email me at ‘; document.write( ‘<a ‘=”” +=”” path=”” ‘\”=”” prefix=”” ‘:’=”” addy47767=”” ‘\’=””>’ ); document.write( addy_text47767 ); document.write( ‘<\/a>’ ); //–>\n or phone me at (519) 824-4120 x 52597.
Weeds
Now is a good time to scout for crabgrass to make note of areas that should be treated in the spring with corn gluten meal. Areas with weed problems other than crabgrass can get the fall treatment with corn gluten meal which will target germinating winter annuals and it should be applied from mid-August to mid-September. Dr. Nick Christians, who was the first to discover the herbicidal properties of corn gluten meal has a very extensive site devoted to it. See the link below. Broadleaf weed control treatments with Sarritor can begin when temperatures cool down. There is plenty of time in the fall to apply Sarritor. Providing the weather conditions are suitable, it can be applied into late September to early October and still give good results.
Fertility
The situation with turf fertilizer is an interesting one. The onset of heat last week resulted in a real surge of turf growth. I think a large amount of the fertilizer that was applied earlier in the season was still lingering but soil temperatures were not high enough to get a surge of growth. I was a bit surprised at how much growth surge there was even on turf that had not been fertilized recently. I would have thought that all the wet weather would have leached the fertilizer out long before now. – See more at: https://lawnsavers.com/turf-hotline-2009/turfgrass-management-agriphone-for-august-17-2009.html#sthash.zc1BRv0C.dpuf
