Weather
That nice gentle fall rain that we had on Mon. Sept. 21st really perked up the turf. Most of the un-irrigated turf was definitely showing signs of drought stress. The nice thing about a rain like that is that it all infiltrates, not like the violent rains that we experience all summer long. The temperatures are near normal or just above normal at the moment, but the long range forecast is for a high or 9ºC next Wednesday. There is light to heavy rain in the forecast for Sat., Mon. and Tues.
Diseases
There has been a big surge in disease activity over the last week. Dollar spot has resurfaced with a vengeance. Fusarium patch began when the temperatures started dipping down to the low teens at night accompanied by the heavy dew formation. We are coming into the window where there will be a lot of pressure from Fusarium patch. The next month is usually conducive to take-all patch development. Don’t forget to apply manganese at 2.25 kg per hectare in October and again in April to help manage take-all patch.
Rust has been very bad this fall. The conditions were just perfect for it. The wet weather followed by the dry weather set things up for rust. Rust starts as yellow lesions on the turfgrass blade that enlarge over time. When they are mature, they produce spores that break through the epidermis of the lesion and are blown by wind and splashed by rain to new infection sites. Most spores are characteristically orange, brown or rust in color. Once rust develops on turfgrass the spores can cycle, producing new spores every two weeks. When the disease becomes severe, the turfgrass stands look yellow. Rust may affect an entire stand of turfgrass or it may be patchy. To help manage the disease at this stage apply nitrogen and keep up with regular mowing. For more information on rust on turfgrass see the Turfgrass diseases.
Insects
Well it has been a veritable crane fly fest out there. Last weekend and most of this week, adult crane flies have been emerging. I would say that the peak adult flights are about two weeks later than last fall. I have had quite a few inquiries about leatherjacket control now that the adult crane flies are flying. I have done one trial using nematodes in the fall for control of leatherjackets and I did not get good control. I also conducted a trial in spring 2009 using nematodes to control leatherjackets and the results were more promising with Steinernema carpocapse giving 30% control. I have plans for another trial using nematodes this fall and am targeting the treatments for mid- late October. This makes it difficult to make a recommendation. The companies that sell the nematodes are recommending fall application to target leatherjackets.
European chafer grubs are developing quickly now. They are mostly in second instar now and it is advisable to halt all of nematode treatments. I expect that damage is going to start showing up in a couple of weeks. Once the damage is noticed it is definitely too late to treat with nematodes.
Last week the turfgrass ant queens (winged ants) emerged from their colonies. Over the season some workers develop into winged males and winged females which are the kings and queens of the ant colony. During the late summer these winged ants leave the nest and swarm. Females and males mate and the males die soon after. The mated female (queen) flies to an attractive nesting site, tears off her wings, and encloses herself in a small excavation in the soil, and lays eggs and a new colony is formed. These winged ants can be mistaken for tiny wasps or bees.
Weeds
We are in the ideal window now for broadleaf weed control treatments with Sarritor. Sarritor is in good supply at the moment. The rain, mild temperature and the overcast conditions are ideal for weed control using Sarritor.
The window for the early fall fertilizer treatment is over now. The next opportunity to apply fertilizer will be in the late fall – late October to early Nov. – See more at: https://lawnsavers.com/turf-hotline-2009/turfgrass-management-agriphone-for-september-28-2009.html#sthash.HNGvUM1b.dpuf
