Weather
There is plenty of rain in the forecast and temperatures are going to be below the seasonal norms until the middle of next week, according to the long range forecast. We did have a few really, nice spring days over the past week. It has been relatively dry and the rain is needed in many areas. There have been some localized dry spots showing up on golf course greens with the warm, dry conditions and high evapotranspiration rates.
Diseases
Finally, Fusarium patch symptoms have stopped. We have seen a few individual dollar spot lesions, but no spots yet on our greens here at GTI. At GTI Turf Diagnostics they have seen some anthracnose basal rot and some take-all patch over the last week. On home lawn turf, there has been some Ascochyta leaf blight on Kentucky bluegrass stands. The symptom of this disease is yellowing and twisting of leaf tips. There are no lesions associated with this disease. High humidity or frequent irrigation favours the disease. It does not causes extensive damage. With the rain in the forecast for the next few days, there is a chance of red thread developing. If you encounter a disease that you can’t diagnose, there is information on submitting a sample to the GTI Turf Diagnostics at the link below.
There is now a biofungicide product in the disease control arsenal for golf courses and sod farms for dollar spot, anthracnose and brown patch based on a bacteria (Bacillus subtilis strain QST713). The product is marketed under the trade name Rhapsody. Rhapsody is a preventative biofungicide and applications should begin when conditions are favourable for disease development.
Insects
On the insect front, this is the calm before the storm. Annual bluegrass weevil larvae should be starting to cause damage. Larval feeding has been going on now for several weeks and we expect so see the typical annual bluegrass weevil damage any day now Damage first appears as small fist sized clumps of yellowing turf on the edges of fairways and on collars. When the turf is examined, it is annual bluegrass that is dying and when you tug on it, it pulls out easily. Also, be on the look out for black turfgrass ataenius damage beginning. It usually is mistaken for drought symptoms or areas where irrigation is uneven. On closer examination, the turf roots have been pruned. European chafter grubs are pupating now and June beetle adults are flying. In a couple of weeks we will start to see the first of the European chafer and Japanese beetle adult flights. Some young hairy chinch bug nymphs have bee reported in the Toronto area.
Leatherjackets are getting pretty much at the end of their feeding cycle. We are still seeing the pecking holes in greens and surrounds made by starling pecking in the greens to feed on the leatherjackets. We have seen some adult cutworms flying around. They will be laying eggs on golf greens at the moment. They lay their eggs on the terminal portion of the grass blade on golf greens. Daily mowing removes the eggs before they can hatch. If you do discard the clippings close to the green, the emerging caterpillars will migrate into the greens. Remember that one of the best ways to avoid cutworm damage is to dispose of grass clippings away from the greens so that the cutworm larvae cannot migrate back to the greens.
Weeds
The spring broad-leaf weed control window for Sclerotinia minor is nearly over. The cool, wet weather over the next week will be ideal for Sarritor. The next opportunity to use this product will be in the late summer. Crabgrass has definitely germinated in most areas now. There are still opportunities to use non-selective weed control actives, acetic acid and fatty acid. Acetic acid can be used as a spot treatment for weeds in lawns. The fatty acid products can only be used to control weeds in patios, sidewalks and driveways. These active ingredients are listed in the searchable pesticide database on the MOE website link below and you can find out the trade names available for those active ingredients. There are also non-selective weeding tools that rely on super-heated water or propane flames that can kill weeds that are available from various suppliers. There are also hand-weeding tools available and many lawn care companies are offering hand-weeding services.
Many cultivars of Kentucky bluegrass are producing seedheads at the moment. These seed heads are tough and difficult to mow. After mowing, the turf will have a gold hue because of all the dead, mowed straw coloured seed stalks. This can be mistaken for a foliar disease such as Ascochyta leaf blight.
Fertilization
We are getting to the end of the spring fertilization window. If turf is irrigated or if we have a wet summer, an application of fertilizer in July is also recommended. If conditions are dry and turf is not growing actively or is dormant, the July fertilizer application is not recommended. – See more at: https://lawnsavers.com/turf-hotline-2009/turfgrass-management-agriphone-for-june-17-2009.html#sthash.X0r4F9vX.dpuf
