winter burn yew

The brown needles on this yew bush are an example of winter burn.

With temperatures still up and down, about the only yard chores we can do is cleanup, raking up leaves and cutting off the foliage of last year's perennials.

The cities of Davenport and Bettendorf are offering free yard waste pickup for the next two weeks (until April 18), and Rock Island is offering the free service until April 25.

A question many people have is how their plants will come through what was a harsh winter.

Just about everywhere you look, you see brown "winter burn" on evergreens, be they needled plants such as yews, spruce, pine, juniper, arborvitae and fir, or broadleafed plants such as boxwood and rhododendron.

Should you get out a pruner and cut out all the brown spots?

No, give your plants a little time, said Richard Jauron, a horticulturist at Iowa State University.

"The brown needles on affected trees and shrubs have been destroyed and will eventually fall off," he said. "However, the vegetative buds on the damaged evergreens may still be alive. Live buds will break in spring and produce new growth.  Evergreens that have sustained light to moderate damage may look much better by late spring.

"A light application of fertilizer in early spring and watering during dry weather will encourage new growth and speed recovery of damaged plants," he said. "Areas that are completely brown in early June are dead and should be pruned out."

So there you have it — wait until June.

But what caused this browning, known as "winter burn," in the first place?

Two things, explained Martha Smith, a horticulturist with the University of Illinois Extension.

One is winter/sun desiccation that occurs when plants are exposed to high winds and full sun and the needles/leaves lose water faster than it can be replaced by roots that are in frozen soil.

Snow cover and sunny days also contribute to this "winter burn" because the reflection off the snow intensifies damage.

The second is salt/deicer damage that occurs on the windward side of plants located along roads or walkways that were treated with deicing salts.

"Flushing water through will help drain the salt out, but take care not to overwater," Smith said.

Another question people have is whether their plants — especially those marginally hardy for this area — will come through, given some of the extremely cold temperatures of the past winter.

Probably not all of them, Smith said. Still, don't be in a hurry to write things off.

"Trees and shrubs are survivors, and with warming temperatures and spring rains, they may pull through," Smith said. "All we can do now is simply wait and see."