Welcome to the “Turf Management Updates” sponsored by the Ministry of Agriculture, Food and Rural Affairs. This message is for the week of July 5 – July 12, 2007.
Weather
After a few cooler, dry days, the temperature is rising and so is the humidity. This trend will continue for a week or so until we get the next round of thundershowers. We had one day of rain yesterday, but there was only a couple of mm’s accumulation in most parts of southwestern Ontario. The rain was just about enough to keep the dust down, but was not significant in helping to replenish the soil moisture.
Dry Conditions
I want to re-iterate the information from last week on water requirements for lawns. A lawn requires 2.5 cm a week of water to keep it green and from going dormant. There is no real problem in letting turf go dormant. A lawn or turf in general can survive for several weeks without water. Usually if Kentucky bluegrass gets 0.5 cm of water every 4 weeks, it will stay dormant, but it will survive. Dormant turf will recover when the rains do finally come. It is just a bit more fragile than a lush green stand of turf. Some general things to keep in mind with drought stressed or dormant turf:
Try to keep traffic off of dormant turf
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Don’t fertilize or mow dormant turf
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Regularly inspect lawn for turf insects
If you are watering turf there a few tips to keep in mind.
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Water in the early morning to prevent evaporation from sun or wind
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Water deeply and infrequently and deliver roughly 2.5 cm of water per week
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This may need to be done in a couple of applications to avoid runoff
Diseases
The relatively cool temperatures, there have been very few foliar diseases besides dollar spot. There were a couple of big dollar spot outbreaks over the last week. This morning, after Wednesday’s rain and with the high humidity overnight, there was a lot of aerial mycelium associated with the dollar spot. With the annual bluegrass weakened from the hot weather, we should start to see anthracnose basal rot developing. There could also be some brown patch and Pythium blight once the temperatures and humidity are on again. Dr. Katerina Jordan has diagnosed several cases of summer patch this week again, as well as take-all patch. If you do encounter diseases that you cannot identify, don’t hesitate to send a sample in to the GTI Turf Diagnostics Lab.
Insects
I really thought that we were at the end of leatherjacket damage, but there are still some areas on our research greens that have heavy leatherjacket populations and there is still some new damage showing up. There has also been a lot of pecking damage, especially after yesterday’s rain. We have passed the window when insecticide treatment for leatherjacket control is recommended.
European chafer adult flights have continued this week. Flights should be slowing down over then next week and ending in the middle of July. Japanese beetle adults are also out at the moment and will continue feeding for several weeks. We are in the ideal application window for preventative grub controls on turf areas that had grub damage in late fall or earlier this spring. Bird’sfoot trefoil is in full bloom at the moment, so that signals peak egg laying of hairy chinch bugs. Expect to start seeing some hairy chinch bug damage showing up in a week or so. If turf is dormant, make sure you still monitor for hairy chinch bug because they can cause a lot of damage to dormant turf.
The caterpillars that we found last week in our soap flushes were black cutworms. We don’t have a heavy infestation here, but there may be larger populations on golf courses at the moment. The damage just looks like very small patches of brown turf that usually appear in a bit of a cluster. The turf is chewed away down to the crown. The turfgrass ant is still active on the outer perimeters of sand based golf greens. Treatments are most effective when made earlier in the season. At this time of year you can usually only expect control for a couple of weeks.
– See more at: https://lawnsavers.com/turf-hotline-2007/turfgrass-management-agriphone-for-july-6-2007.html#sthash.HSjIf5JS.dpuf
