Obsolete pesticide collection – coming to Ontario this fall.
Archive for May, 2013
Obsolete pesticide collection – coming to Ontario this fall
Posted in Pesticide Registration on May 31, 2013| Leave a Comment »
Conditions ideal for leaf spot and melting out
Posted in Diseases on May 29, 2013| 1 Comment »
If this phase of the disease occurs, the best control is to raise the mowing height. A light application of nitrogen fertilizer after the hot, humid weather passes will help the turf recover from melting out damage. If the turf is irrigated, avoid over-irrigating.
Dollar spot around the corner
Posted in Diseases, Uncategorized on May 23, 2013| Leave a Comment »
Dollar spot is favoured by warm, humid days followed by cool nights that produce heavy dew formation. Removing dew by mowing, rolling or polling greens and adequate nitrogen fertilization are practices that will help to minimize this disease, but preventative fungicide applications are the backbone of dollar spot management.
Peak leatherjacket damage
Posted in Insects on May 21, 2013| Leave a Comment »
What will be evident, especially in urban areas that are infested with leatherjackets, is large numbers of leatherjackets forced out of the turf after rain storms like the ones that are currently moving through the area. Don’t be alarmed, this is actually a good control measure as the leatherjackets will usually end up dying once they are forced out of the turf.
Our research on leatherjacket control for home lawns has been focused on using insect parasitic nematodes and we have had very low success when the nematodes were applied in the spring (<30% control). Our results with fall applied (late October/early November) nematodes have been inconsistent with good results some years and poor results in other years.
For golf courses, both carbaryl and clothianidin can be used at this time of year. The other insecticides that are labeled for control of leatherjackets are best applied in the fall as a preventative application.
The first wave of crabgrass has germinated
Posted in Weeds on May 21, 2013| 2 Comments »
Timing for annual bluegrass weevil larvaecide approaching
Posted in Insects on May 17, 2013| Leave a Comment »
Our twice a week soap flushes for annual bluegrass weevil adults put the peak adult migration in the Guelph area around May 6th this year. This is consistent with a project that Dr. Brenda Nailor is working on for the Weevil Trak program with Syngenta. She tracked peak adult migration on May 7th. That would have put the timing for an adulticide around that time.
If your preference is to target the early larvae, then the timing for a product like chlorantraniliprole is to apply it 2-3 weeks after the peak adult migraton. This is coming up quickly. We predict the best timing in the Guelph would to be May 20-30th. The product needs to be applied and taken up by the turfgrass plant and be in the plant as the young stem boring larvae start feeding.
If your preference is to use clothianidin, the window of application is slightly later. It is aimed against the 2nd and 3rd instar. We have started our salt solution flotations (place a plug of turf in a mixture of 36 grams of salt per 100 mL of water) this week to track the larvae and will keep you posted as what we find and when. To date we have not found any young larvae.
One last comment, the emergence of the annual bluegrass weevil adults seems to have been very synchronous, mainly due to an extended warm spell during the migration. My gut feeling is that this will greatly help the efficacy of controls whether it be the adulticide or the larvaecides.
Annual bluegrass weevil on the move
Posted in Insects on May 2, 2013| Leave a Comment »
Just a note on plant phenology, the very first wave of migration seems to coincide with the first bloom of Forsythia. In the Guelph area, they started to bloom a few days ago, so the timing is almost spot on for this first wave of ABW migration.
The suggested timing for an adulticide is when the forsythia are half green/half gold. So, don’t get your sprayers out yet. With this nice weather the Forsythia will probably progress quickly, but I guestimate that we are at least a week away from this stage of Forsythia development. Information on a larvaecide application timing with a product like chlorantraniliprole is less clear. The concensus in the field is that the larvaecides should target the 1-3rd weevil instars. That timing would be roughly the same time, when the Forsythia are half green/half gold. The thing is that both of these products are quite residual so the timing is not so critical and my gut feeling is that you should err on the early side not the late side. The clothianidin label says to target the 2nd and 3rd instar, so it should probably go on a couple of weeks after the half green/half gold stage of Forsythia.
Stay tuned.