PLEASE NOTE: The Following Pesticide Recommendations are meant for Excepted Uses (e.g. golf courses and sod farms) under the Cosmetic Pesticide Ban. Only the active ingredients listed under Class 11 pesticides in Ontario Regulation 63/09, can be used on home lawns and sports fields and other non-excepted uses.
It was great to finally get some heat early last week. The spring turf growth flush halted a little bit because of the high heat. The long term forecast for the upcoming week is for sunshine for all but three days. There are thundershowers in the forecast for Sat. June 4th and isolated showers for Mon. June 6th and Thurs. June 9th. The rest of the days will have dry conditions and seasonal temperatures with high’s in the low to mid 20’s and night-time lows of 12-15°C. The day time temperatures are seasonal, but the night time temperatures are a few degrees above seasonal. In total, the forecast is for 8-12 mm of rain in the next 5 days. The winds have been very strong early in the week (June 1 and 2nd). This is helping to dry up the very, very wet areas on golf courses, sod farms and sports fields. We now have areas with standing water and within a few metres of that there are localized dry spots. The high winds brought down a lot of trees and there was a lot of clean up to do, especially on golf courses.
As predicted by the plant phenological indicators and the predictive models, dollar spot started last week. We saw active mycelium on Mon. May 30th and Tues. May 31st. The low relative humidity and cool nights will temporarily halt the dollar spot pressure. The yellow patch that was so prevalent, is nowhere to be found. The cool nights, especially if there is a heavy dew, will cause the Microdochium patch to flare up again. The drier conditions, clear skies and the high winds will also bring on take-all patch symptoms. We have seen take-all symptoms starting to show up this week. Red thread is no longer active, but it could flare up if we get prolonged wet conditions and cooler temperatures. If you are fertilizing turf at this time of year, that also helps suppress red thread.
There are a few things that are visible on golf greens that can be mistaken for diseases. There is some scalping of turf that was mowed when wet and annual bluegrass tillers that are dying off after flowering have caused some yellowing of the turf. Also, annual bluegrass weevil damage can sometimes be mistaken for a disease.
Though not a disease, the blast of heat has sent many Kentucky bluegrass plants into flowering. This gives the turf an uneven appearance, especially when the seedhead stalks are mowed. Many of the cheap Kentucky bluegrass cultivars are cheap because they are prolific seed producers.
If you do encounter a turf problem that you can’t identify, you can always send a sample to GTI Turf Diagnostics. Information on this service is available on the GTI web site. You can also email them at diagnostics@guelphturfgrass.ca or telephone at (519) 824-4120 x 58873.
As predicted last week, June beetle adults are flying now. They are large dark brown beetles that fly at night. They are attracted to light and you can often find them banging into screen doors or sliding glass doors if there is an outside light on. They have a three year life cycle and more information on them can be found on the OMAFRA website in the factsheet “Grubs in Lawns”
If you are contemplating making a larvaecide application to control annual bluegrass weevils, this is about the ideal time. Monitoring for the larvae can be accomplished by putting a turf core in a saturated salt solution. A saturated salt solution can be made by combining 35 g of salt for every 100 mL of water. All stages of annual bluegrass weevil will float in this solution.
The plant phenological indicator for peak adult flights of black turfgrass ataenius (horse chestnut and bridal wreath spirea) are in flower at the moment. Also adults have been observed on golf greens in the mid-afternoon on the warm sunny afternoons this week. Preventative applications for areas with a history of BTA damage can be treated now.
Leatherjacket pupal casings have also been observed on golf greens over the last week. This is from the emergence of the common cranefly (Tipula oleracea). This leatherjacket has two generations a year and adults emerge in the month of May and in September.
Weed control products and timing
Dandelions are in the puff ball stage at the moment. This is still a good window in which to apply broad leaf herbicide applications, whether you are applying Class 9 herbicides on golf courses and sod farms or Class 11 herbicides on non-excepted areas. I would say, based on our Fiesta treatments so far that a second application is needed to control broad-leaf plantain and clover. The dandelions look dead, but there will probably be some re-growth. We have also applied Fiesta to prostrate knotweed and the results look very promising to date.
With the blast of heat and the thundershowers earlier in the week, crabgrass has germinated in open areas.
Aeration and fertilization
It is getting a bit late for spring aeration, but if you get it in next week while the temperatures are moderate there is a good chance of the holes healing over before we get more heat. It is also a good time for the first spring fertilizer treatment. The fertilizer treatment is especially important if you have applied a broad-leaf herbicide. It will help the turf fill in the bare areas left when the weeds die.
The deadline for posting the golf course 2010 Annual Report– Pest Control Product Usage and associated maps is coming up quickly. Both of these documents must be posted in a public area of the golf course and on the IPM Council of Canada website before June 30, 2011. Golf courses that submitted their 2010 desk reviews in paper form must obtain a user name and password for the Members Only portion of the website and upload their 2010 Annual Report and map before June 30, 2011. For more information, go to IPM Council of Canada web site and click on the Members tab. There is also more information on the preparation and posting of the annual report in the Technical Guidance – Pesticides Act and Ontario Regulation 63/09 Golf Courses posted on the Ministry of Environment web site. I appreciate the feedback. You can reach me by phone or email at (519-824-4120 x 52597) or by email at pamela.charbonneau@ontario.ca.
– See more at: https://lawnsavers.com/turf-hotline-2011/turfgrass-management-agriphone-for-june-3-2011.html#sthash.gH0wQUPs.dpuf
