Winter tough on Southcentral turf

When their ice-encrusted lawns finally thawed in late May, property owners living at Homer’s lower elevations found broad swaths of brown where they’d come to expect explosions of green. 

Let’s face it: Winter was tough on the turf.

Cold fall temperatures were followed by limited snow cover during the winter that turned to sheets of ice. And thanks to the later-than-normal thaw, that condition lasted well into May. The result was suffocated roots, said Lydia Clayton, the University of Alaska Fairbanks Cooperative Extension Service’s agriculture and horticulture agent based in Soldotna.

Lawns look diseased, but the condition is not snow mold. “This is a climatic issue,” she said.” Like any plant, grass root systems need to breath. “The ice sheeting limited oxygen getting the roots.”

When the dead areas finally thawed, property owners likely detected a distinctive odor, similar to an ammonia-based fertilizer, the type of smell wafting from an unturned “anaerobic compost pile,” Clayton said.

Some species of grass and other plants conditioned to Alaska’s climate generally survive such conditions. But grass seed mixtures often contain species that don’t do as well harsh winter conditions and they succumb, Clayton said.

“We had a pretty long stretch (of years) when marginal plants were thriving,” she said. “But we live in Alaska in zones that are not really temperate, and every so many years, we get climatic conditions where some species will not survive. They can’t survive forever.”

So what’s there to do about those enormous areas of lawn resembling parts of California in September? Nature has presented you with some options, Clayton said.

“Think about putting in those perennial flower beds you’ve always wanted. You can do it without having to take out the lawn; nature’s already done if for you,” she said.

If you want to reestablish a lawn, you can simply wait for healthy areas to spread. But that could take a year or two during which time you will have to control weeds that likely will reestablish first. She recommended some light soil fertilizing where grass is actively growing. 

If you want to re-seed, create a good seed bed by breaking up the hardpan. Clayton recommended aerating – punching holes in the turf – and thatching – raking to remove the dead grass roots system. According to the Extension Service website, Kentucky bluegrass and red fescue varieties tend to do well in Alaska. The mixture percentages will depend on how shady or sunny your lawn area will be. It is important to properly prepare the soil.

“You want to get good seed-to-soil contact,” Clayton said.

Perennial ryegrass often is present in commercial lawn mixes as a “nurse grass” because it germinates quickly and helps retain moisture that while other species are getting established. Ryegrasses don’t generally survive winters, however, and shouldn’t be used to overseed grass on an established lawn.

For a wealth of useful tips on lawn preparation and care, Clayton recommended downloading an eight-page publication from the Extension Service’s website. Here is the link: http://www.uaf.edu/files/ces/publications-db/catalog/anr/HGA-00045.pdf 

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