This is the 7th edition of the “Turf Management Report” sponsored by the Ministry of Agriculture, Food and Rural Affairs and it is for the week of May 20 – 27, 2011.
There is one technical issue that I want to make you aware of and that is that we are currently unable to record the podcasts of this message. It is still available at the 1-888-290-4441 number and as text on the OMAFRA web site however.
PLEASE NOTE: The Following Pesticide Recommendations are meant for Excepted Uses (e.g. golf courses and sod farms) under the Cosmetic Pesticide Ban. Only the active ingredients listed under Class 11 pesticides in Ontario Regulation 63/09, can be used on home lawns and sports fields and other non-excepted uses, effective April 22, 2009.
We are due for some warmer weather and it is coming for the Victoria Day long weekend. The trouble is that there is also some rain in the forecast too. So far there is rain in the forecast for Sunday, Monday and Wednesday. Temperatures will be in the range of 18-24°C during the day and 10-15°C during the night. This forecast, along with the weather over the past week or two is setting things up for a lot of turf disease development.
Microdochium patch has exploded over the last week. What makes it difficult is that it has been difficult to get out and make a fungicide application because it has been too wet. On the plus side, as the temperatures warm up the Microdochium will stop spreading and the patches will heal. Yellow patch has also exploded. In my career to date, I have never seen this much yellow patch. Usually there are one or two rings, but this year some of the greens that I have seen may have twenty or more of the yellow rings. The weather has been conducive to anthracnose basal rot, but to date the GTI Turf Diagnostics lab has not received any samples with this disease. As things warm up and soils remain saturated, this disease is likely to show up. Light topdressing will help, as well as increasing fertility. University of Massachusetts Turf Extension web site has some good information on anthracnose basal rot posted by Bess Dicklow.
On Kentucky bluegrass there is a lot of leaf spot showing up. So far it is just at the leaf spot stage but if we do get hot, humid conditions in the next couple weeks it has set us up for the melting out phase of leaf spot. This is mostly a problem on home lawns and Kentucky bluegrass fairways, roughs and sports fields.
Another phenomenon that will occur shortly associated with annual bluegrass seedheads is general decline of annual bluegrass plants. Once the plant flowers, the leaves will die off. When this happens the annual bluegrass plants appear yellow and off colour. Another issue that could be mistaken for disease this time of year if scalping injury due to the saturated soils and the speed at which the turf is growing.
If you do encounter a turf problem that you can’t identify, you can always send a sample to GTI Turf Diagnostics. Information on this service is available on the GTI web site. You can also email them at diagnostics@guelphturfgrass.ca or telephone at (519) 824-4120 x 58873.
Someone pointed out last week that I recommended using nematodes on golf courses in mid-summer to control grubs. This timing is incorrect. The timing for applying nematodes to control grubs is in August to early September regardless of whether you are treating a home lawn or a golf course. Grubs will be coming to the end of their lifecycle very soon and will be pupating by early June (I think that pupation will be slightly later than normal this year because of all the cold weather).
The window for making adulticide applications to control migrating annual weevils is over. You have up until the forsythia are half green/half gold. Many of the forsythia bushes in the landscape are in that stage now. The next option is a larvacide (clothianidin or chlorantraniliprole) and this should not be done until the soils dry out. It is not advisable to apply these products to saturated soils.
Another insect pest that is just starting to become active is the turfgrass ant. Most pesticide labels for ants say to apply as soon as the mounds first appear. The choices of pesticides are pyrethroids, carbamates and spinosad. None of these products really give prolonged control. It is also important to adhere to the number of treatments stated on the label to avoid insecticide resistance developing. It is also usually only necessary to treat the perimeter of a golf green, which is where the majority of the ant mounds occur. Also, if there are any companies out there with products that they think might work on ants, I would be happy to conduct a research trial on ants. We have a couple of perfect sites here at GTI with lots of ant mounds.
I have not made mention of leatherjackets for a few weeks, but there have been some calls and emails about leatherjackets. There are some areas that have been hit very hard with leatherjacket damage. After the rains, the surface of the soil (and what is left of the grass) was covered with leatherjackets. Also, some golf courses are observing leatherjackets on the greens in the morning as they are mowing. For home lawns there is really no solution to the leatherjacket problem. The good thing is that leatherjacket feeding damage has almost peaked. I would say after next week there should not be more new damage from leatherjackets.
On golf courses feeding damage on greens is rare. If populations are high, there might be damage from birds feeding on the leatherjackets and in some cases that may warrant an insecticide treatment.
Weed control products and timing
Dandelion bloom has peaked and next week we should see a sea of white seedheads and dandelion seeds blowing everywhere. Once things dry up, we are in the ideal window for post-emergence broadleaf weed control with Fiesta.
Once the soil dries out it is a good time to schedule the spring aeration. It is about time to apply the first fertilizer treatment of the season. We usually recommend that you fertilize towards the end of May/beginning of June.
Again, keep the emails coming. I appreciate the feedback. You can reach me by phone or email at (519-824-4120 x 52597) or by email at pamela.charbonneau@ontario.ca.
– See more at: https://lawnsavers.com/turf-hotline-2011/turfgrass-management-agriphone-for-may-20-2011.html#sthash.bODxrm6O.dpuf
