Welcome to the “Turf Management Report” sponsored by the Ministry of Agriculture, Food and Rural Affairs. This message is being recorded for the week of May 22 – 28, 2007.
Last week was a bit warmer than seasonal, except for the Sunday of the long weekend, which was below seasonal. Areas that received thunderstorms last week probably are just starting to dry out now. The forecast is for a couple of hot days mid week and then back to seasonal for the rest of the week and the weekend. There is only a chance of showers on Fri..
This week there was some more yellow patch and Pythium root disfunction diagnosed at GTI Turf Diagnostics. On our research greens there is some lingering Microdochium patch and we may see a small flare up of this after the cool weather last Sunday. It is a slow developing disease at this time of year and the symptoms often lag behind the infection event by a week or so. On home lawns there has been some really pronounced necrotic ring symptoms already this year. I am not sure what to attribute it too, but it could be a result of the wet fall and then the relatively dry spring. Just a reminder to send any unknown turf problems to the GTI Turf Diagnostics.
Grub calls should slow down now. Grubs will be pupating over the next couple of weeks. We are about mid-way through the annual bluegrass weevil migration. I have not seen too many adult weevils, but many golf courses are reporting seeing them. Aphodius flights will be slowing down now. Full bloom of horsechestnut trees signals the time for peak flights of turfgrass ataenius adults. There is still time for preventative control of black turfgrass ataenius if you have seen large adult flights or if you have had a history of damage on your golf course. They are usually about 2 weeks behind the Aphodius. The type of damage that occurs with each of these grub species is very similar and usually occurs in late June to early July.
The thunderstorms last week, again drove many leatherjackets out of the grass and on to hard surfaces. The leatherjackets are mainly in the fourth instar now and are feeding very heavily. We see new damage daily here at the GTI. Treatments with Sevin T&O can be used any time now to control leatherjackets on home lawns, golf courses or sod farms. There are several restrictions on when and how Sevin T&O can be used on residential properties. These include: one application a year; treatment should be considered at or above 270 larvae per m2 and spot treatments only are allowed in residential areas and not more than 100 m2 area can be treated on a residential property.
Another insect that is just starting to become active is the turfgrass ant. They are starting to build their mounds now. They do not eat the turf but feed on other insects present in the turf and soil beneath the turf. The reason that they are a problem is that they form sandy mounds in golf course greens, tees and fairways. These mounds can suffocate the turf, they increase maintenance costs by dulling mower blades and on greens they can disrupt the playing surface. They tend to be more of a problem on new golf courses that have never been treated with the persistent organochlorine insecticides that were used on older golf courses in the past. They are usually within 1-2 m of the edge of a green. Dursban is registered to control ants and according to many recent trials in the U.S. gives good control. Scimitar (lambda-cyhalothrin) is also registered for control of ants on turf.
I was in Toronto late last week and crabgrass is starting to germinate in open areas near hard surfaces such as driveways and sidewalks, were salt has damaged turf. In most areas now the window in which to apply corn gluten meal is finished. At this point, a product like Dimension is still recommended because of the early post-emergence activity. An alternative approach is to wait and apply a post-emergence herbicide on the small crabgrass plants, once they have germinated. This might be the best approach for golf courses, especially in areas that may need to be overseeded sometime during the growing season. Post-emergence products are not residual the way the pre- and early post-emergence products are.
Dandelions are ranging now from full bloom to puff-ball stage in many areas at the moment. We are coming into the ideal post-emergence weed control window. Of course, it is important to be aware of any by-laws restricting the use of any kind of herbicide on home lawns. For instance, in the City of Toronto broadleaf herbicides are not allowed at all and only corn gluten meal can be used for crabgrass control.
Annual bluegrass seedhead production has probably peaked at the moment. There are some pretty unattractive putting surfaces out there at the moment.
Turf that hasn’t been fertilized yet this season should receive some fertilizer in the next two weeks. There has been good root growth so far this spring. Now that the roots are growing well, it is a good idea to fertilize turf soon so that you can promote a dense turf stand. It is also good to fertilize after a herbicide treatment so that the turf can fill in the voids where the dead weeds are.
– See more at: https://lawnsavers.com/turf-hotline-2007/turfgrass-management-agriphone-for-may-23-2007.html#sthash.1oaCcBp9.dpuf
