We continue with our fall maintenance and prep for winter. Aside from the tree removal for pine beetle (previous post) and aerating greens with the deep tine aerator, we have begun our winter disease prevention program. Right now we are in better shape (health and treatment wise) than last year. Temperatures have been in a nice range with overnight lows only moderately below zero (versus 10 to 15 below zero last fall) and day time highs anywhere from +5 to +12 C. We require 2 more preventative sprays on the greens to properly preparing them for winter.
Applying Snow Mould
Treatment on 12 Fairway
The funny thing about preventative sprays is the timing. An application needs to be before conditions are right for disease to fully
develop but not so soon that you risk the treatment loosing its
potency. Two of the green sprays need to be done while the turf is still able to absorb the treatment; i.e. still growing/photosynthesising. The recommendations for the third application is to apply just before the first permanent snow cover. The "just before the first permanent snow cover" is the weird part. Weather forecasts, historical averages, and my "
spidey sense" are the only tools I have to decide when to time that last spray.
One problem with spraying too early is the affect moisture has on spray efficacy. The more a treatment is exposed to rain events or snow melt (with respect to a contact fungicide) the less effective is its control. Aside from rain, UV light can also lessen fungicide effectiveness as a result of UV degradation. One more thing: fungicides have recommended spray intervals that range from 7 to 28 days depending on
environmental conditions and disease severity. Snow cover obviously limits re-applying so, ideally, you would want to be at the beginning of the time line with respect to the spray interval when the snow does come.
We can spray all 18 greens with just over one tank so it only takes 3 to 4 hours to finish. When it comes to treating the rest of the golf course we need another 10 tanks which, when you throw in frost delays and the time needed to have spray dry on the leaf, can take up to 5 days to complete the 10 sprays required.
