|Now that the snow is melting, many of us in the mid-atlantic area are seeing extensive damage to trees, shrubs and perennials. How about a column dealing with these problems, including the topic of snow mold? Please|
|Great idea! I'll pass your message along. In the meantime, the best way to deal with winter damage is to sharpen your pruners, but wait until new growth begins so you know what's actually dead and what is simply slow to recover from the deep freeze. Patience is a virtue when dealing with winter damage. It's safe to prune away all the winter damage and then prune the rest of the tree, shrub or perennial so it has an equal, more natural shape.
Snow mold is a fungal disease that appears in early spring as the snow melts. There are two types of snow molds, gray and pink, that become active under the snow cover. Gray snow mold (also called Typhula blight) is caused by Typhula spp., while pink snow mold (also called Fusarium patch) is caused by Microdochium nivalis.
Symptoms first appear in the lawn as circular, straw colored patches when the snow melts in the spring. These patches continue to enlarge as long as the grass remains cold and wet. Grass within the patch often has a matted appearance and colored fungal growth. The fungal growth may cover the entire patch or develop along the margins, with gray snow mold being white to gray in color and pink snow mold being white to pink in color. Occasionally, fungal fruiting bodies (mushrooms) may be seen emerging from infected turf. Hard structures, called sclerotia, may also develop on the leaves and crowns of plants infected by gray snow mold, not pink. The sclerotia are spherical in shape and roughly the size of a pinhead. Their presence helps to distinguish gray snow mold from pink snow mold.
The damage caused by snow molds is seldom serious. Generally, infected areas are just a little slower to green up. Gently rake affected areas of the lawn to promote drying and prevent further fungal growth. Fungicides are not usually recommended, but in severe cases a preventative spray of thiophanate-methyl (Cleary's 3336) in October or November may help to avoid the problem next year.