By Mary Beth Pottratz
A snowperson with an artful face and stick arms stands sentinel over a playhouse at the Shade Tree Exhibit. I squint in the sun, which is bright even though it is behind thin waves of clouds. Today’s temperature is blissfully above zero with very little wind. Snowshoers, hikers and cross-country skiers are out enjoying the trees and fresh air at the Arboretum.
A wild turkey plays hide and seek with me from behind a curtain of grasses, making me laugh.
Two sets of animal tracks lead to and from a sheltered spot beneath a bench. What a convenient place to hide from airborne predators!
And there is additional protection beneath the snow, in what is called the subnivean zone. At ground level, condensation rises and freezes (or sublimates) the snow into a ceiling, creating a relatively warmer, wind-free environment. Small mammals and birds burrow through the layers of powder, wind-packed snow, frost and the ice-roofed layer just above the ground. You can often see the subnivean layer yourself by using a large, flat snow shovel or cookie sheet to “slice” the snow open.
Arboretum members Maureen and Kevin are hiking this winter wonderland. Maureen loves the way she can see deep into the woods without the leaf cover. Kevin enjoyed learning about the Eastern hemlock on their hike, an evergreen that is classified as endangered in Minnesota. He would love to help plant seedlings in efforts to protect this tree. A nearby nuthatch calls in series of loud alarm calls, and Kevin confirms it.
There are several paper wasp nests still visible on bare tree trunks throughout the Arb. Look closely, and you can see the striations on the outside of the nest. They are due to the wasps chewing different varieties of dead woods, softening it with their saliva, and layering the resulting goo to create the outer walls of the nest. The mixture dries to a stiff, thick paper, and the wasps create honeycomb-like frames inside. Paper wasps pollinate flowers while searching for nectar. They also consume large quantities of insects!
Tamarack trees sport cones and spurs that were hidden behind their needles last fall. The small cones feel like balsa wood – light and airy, but their scales are shaped like petals. Chickadees call some new songs from above, “Chik-brrrr” and a long “Feeee beeee”. I think they are wishing January farewell.
It’s hard to tear myself away from these warmer temperatures, but as I head home, I am glad to wish January goodbye as well.
Mary Beth Pottratz is a Minnesota Master Naturalist Volunteer.. More information about the program is available at www.MinnesotaMasterNaturalist.org.