Extension Educator, Horticulture
Stockpiled snow has finally surrendered to salt and sun. Unfortunately its retreating has exposed my shaggy dog of a lawn. If only I could send it out for a wash and a blow-dry. Long periods of snow cover can cause a myriad of lawn woes.
Many lawns weren't picture perfect going into winter. Snow is nature's air brush; it masked the flaws but didn't really improve the lawn's condition. As snows recede lawns may show damage from salt, plows, voles and molds.
Salt can cause death of lawn grass or cause severe browning of grass blades, generally near sidewalks and roads. Removing any obvious salt and flushing area with water may help. However, right now more water can cause other problems. Wait until April and reseed areas.
If snow plows have scraped off lawn areas, use your best jigsaw puzzle skills and set sod pieces back into place now. Do a little spring dance to assure good soil contact. Sod should reroot.
A couple species of voles can inhabit your yard. Voles can make runways under the snow in lawns as they feed on grass blades and roots. Voles are well protected under the snow from hawk and owl predators. Voles may have brown to reddish-brown fur and range from 4 to 7 inches long. They have stockier bodies and shorter tails than mice. Damage is frequently mistaken as mole damage, but moles are not active during winter. Vole damage appears as surface runways or winding trails of damaged grass. Damage also occurs when my dog tries to dig out the aforementioned voles.
Once spring arrives grass will usually grow into and fill-in the surface runways; however, severe damage may require some overseeding of lawn grass in April. Voles love tall vegetation; therefore, prevent damage from occurring by continuing to mow lawns to a height of about 2 inches until grass is completely dormant in fall. Also in fall clean up any excessive vegetation near lawns.
Check out this website for more information on voles and other wildlife. http://web.extension.illinois.edu/wildlife
Snow mold damage can also be very visible on lawns as snows recede in spring especially if we get a prolonged snow cover on unfrozen soil. Both gray (Typhula blight) and pink snow mold (Fusarium patch or Microdochium patch) may occur. During the wet, cold weather of early spring, snow mold may be highly visible as matted, crusty looking areas. Gray snow mold appears in roughly circular yellow to whitish-gray patches. As conditions dry out, snow mold will gradually go dormant. Often just leaves are affected and new grass blades grow as weather warms. Severely infected areas may remain in the form of weak or even dead turf. To repair damage, rake matted grass and re-seed or resod as necessary in April.
Snow mold severity varies from year to year. Fungicides are generally not needed. Ways to avoid snow mold problems include: follow sound fertilization programs; use fertilizers containing slow-release or controlled-release nitrogen; and manage thatch via aerification or removal with vertical mowing (dethatching). Surface drainage should be adequate. Improve air circulation by pruning or removing dense vegetation bordering problem lawn areas and removing deep layers of leaves from lawns in fall. Damage from voles and snow mold can be minimized by keeping lawns mowed until grass is completely dormant in fall.
Check out these great University of Illinois Extension websites for more information on lawn care. Lawn Talk http://www.urbanext.uiuc.edu/lawntalk/ Frequently Asked Lawn Questions http://urbanext.illinois.edu/lawnfaqs/ and take the Lawn Challenge http://urbanext.illinois.edu/lawnchallenge/
Forget about your lawn and join Vermilion County Master Gardeners at their 2014 Garden Day Workshop and Spring Festival Saturday, March 8 from 8:00 AM - 4:00 PM at CrossRoads Christian Church (3613 North Vermilion, Danville, IL). Great garden programs and shopping. To register http://web.extension.illinois.edu/cfiv/vermilionmg/ or phone UI Extension 217-442-8615.