Weekly Update

Cool season grasses will green up at varying speeds. The diversity among the grasses is easy to see this time of year (left). Poa annua and Poa trivialis have an apple green color and green up rapidly once soil and air temperatures get above 50°F (10°C). Perennial ryegrass can easily be identified by the shiny, dark green nature of the turf at this time of year compared to the more dormant Kentucky bluegrass. Cultivars of Kentucky bluegrass that have slightly quicker spring green-up may be beneficial for spring sports, such as baseball. Cultivars are listed on the NTEP website.

Late season fertilizer applications made last November/December will significantly boost spring green-up. Those field managers that have growth blankets can also achieve much quicker spring green-up.On this particular field (left) the growth blanket was put down in early February and removed late March. The end of the field did not get covered and it is easy to see the difference in color. Growth blankets can cost around $12,000 which can be cost restrictive for a lot of field managers (particularly at high schools) but they can offer big benefits to those turf managers that have spring games. They can also be advantageous during seed establishment.

At least three field managers have contacted us recently about strange trails going through the turf that are seen when snow cover is lost or growth blankets are removed (left). These trails have been made by voles. The voles tunnel through the grass eating grass blades and roots. The turf usually recovers in spring when the temperatures warm up but severe damage might need over-seeding. Discouraging the vole activity is difficult but mowing right up to the end of the growing season may prevent invasion.

Following on from the posting on pink snow mold (Microdochium nivale) two weeks ago, these pictures were taken to show the damage incurred by the snow mold. The turf areas most severely damaged were the annual and transitional ryegrass plots. It would appear at this time that the turf will not recover adequately in those areas and that they will need to be re-seeded.

There have also been some reports of snow mold incidence this winter on fields that were treated with the contact fungicide "PCNB". Joe Rimelspach did a posting recently on the efficiency of PCNB, which can be accessed HERE

Authors: Pam Sherratt & John Street