By Pam Charbonneau
OMAFRA turf specialist

It is a watershed moment in Ontario’s turf industry with the Cosmetic Pesticides Ban Act taking effect on April 22, 2009. It is no longer business as usual in the turf industry. It also influences what I can recommend in this column. OMAFRA remains committed to helping identify solutions to your pest management problems that will fit into the biopesticide category that has been designated for use on home lawns and gardens in Ontario. Use of good cultural practices, fertilization, irrigation, mowing, aeration, overseeding and topdressing will be more critical than ever to help customers maintain healthy lawns. Managing expectations in the event of insect and weed infestations is going to be a necessary, yet tricky business.
 

Snow mould damage is widespread

The snow melt in early March gave a clear indication of the extent of the turf damage that occurred under the snow. There is a lot of pink snow mould to deal with and a touch of grey snow mould.  Many winters only result in snow mould in the areas where snow is mounded, as a result of plowing streets and shoveling driveways.  This spring the snow mould damage is much more widespread than in the past, due to the very prolonged period of snow cover.  

The recommendation to deal with the snow mould scars has not changed over time. Also, as usual, the damage is most often superficial, or on the leaves, only with usually no crown (or permanent) damage to the grass. Rake the damaged areas to encourage them to dry out and apply a light application of fertilizer to encourage the grass plants to grow quickly and replace the dead leaves with new ones.

The extremely wet season last summer and fall meant that there was not a lot of evidence of European chafer damage in the late summer and early fall. This could change rapidly this spring when the mammals and birds that prey on grubs start to become active. The axiom for spring control of grubs with insecticides holds true for spring control of grubs with nematodes: don’t bother. Do make a note of customers who do have grub damage and order your nematodes in advance. The ideal timing for applying entomopathogenic nematodes for grub control is in mid- to late-August and early September at the latest. Water before application and water after application and preferably apply the nematodes on a cloudy day or in the evening or early morning. The Heterohrabditis bacteriaphora (Hb) species or a combination of Hb and Steinernema carpocapse seem to work best.  
 

Leatherjackets had ideal conditions

Back in the fall, conditions were absolutely ideal for the hatching and development of leatherjackets. We have not been completely successful in determining the appropriate nematode species for leatherjacket control. It would appear that the best timing is in the fall when the leatherjackets are young and small. The complication is that at that stage, they don’t live or feed in the thatch or soil, but at the very top of the thatch in amongst the leaf blades. This makes it difficult to target them with nematodes that usually reside in the soil and are susceptible to ultraviolet light, if not watered in. We will do some trials in the fall with various nematodes species, rates and timing as well as looking at surfactants to allow the nematodes to hold on the plant for a long enough period of time to infect the small leatherjacket larvae.

On the subject of leatherjackets, in spring 2007 it was confirmed that there was a new species of crane fly in Ontario. It is the common crane fly, Tipula oleracea. It is thought to have two generations per year in this area. Adults fly in May and again in September, unlike the European crane fly where adults fly only in September. We are interested in finding out more about this new species of crane fly. We are asking for the assistance of golf courses, lawncare companies and sod farmers in Ontario. If you see adult crane flies flying during the month of May, I would appreciate if you would contact me by phone at 519-824-4120, ext. 52597, or by e-mail at pamela.charbonneau@ontario.ca. I would like to collect samples and identify them to see exactly where in Ontario this new species currently exists.  

Here is wishing you good luck in the upcoming season with the new legislation.