by Barbara Walvoord
Way back into history, the shortest days of the year have been a time to fear cold, storm, hunger, and evil spirits. Evergreen trees symbolized the ability to survive the winter and the promise of a green earth. People brought evergreens into their homes as protection against evil spirits.
Today, many Lathrop residents will bring cut Christmas trees into their homes, but our Lathrop land–our wider home–has thousands of evergreen trees, not just symbolizing the ability to survive the winter, but actually helping our creatures do so.
The two most common evergreen trees on Lathrop land are eastern white pine (Pinus strobus) and eastern hemlock (Tsuga canadensis). Together with our red maples and white oaks, they form a common type of New England forest that, if kept healthy, nurtures a rich diversity of wildlife.
One thing our evergreens do is provide dinner: seeds of white pine and hemlock feed rabbits, squirrels, bears, and many birds includingturkeys and blue jays. The bark of white pine is dinner for beaver, rabbits, porcupines, and mice.
A relatively small number of very tall white pines form a supra-canopy in the forest that serves as a high perch for mother bears to stash their cubs and eagles to nest. When dead, as snags, these tall pines host hordes of bugs for woodpeckers and others, and, when they fall, they deteriorate very slowly, forming a rich environment for all kinds of plants and animals.
Our evergreens also provide nests for grackles, mourning doves, chickadees, and nuthatches, and woodpeckers. A large hollow hemlock trunk makes a nice den for a bear.
We modern humans have given up our belief that evergreens harbor wood nymphs or combat evil spirits, but our evergreens do hold magical promises of spring to come–overwintering caterpillars that will change into butterflies and moths. Scientific studies by Douglas Tallamy and others show that pine supports 191 different species of butterflies and moths (Lepidoptera); hemlock supports 89 species.
Many of these moths and butterflies have fed on evergreen needles during summer and autumn, and then fallen to the earth below the tree to spend the winter in a cocoon in the soil. Come spring, they will magically emerge to feed on pine needles, beginning once more the cycle of seasons that marks the life of our Lathrop land. https://www.dropbox.com/s/stytn1v85b6aa2j/tallamy%20copy%20of%20webplants.xls?dl=0.
This beautiful pine-devil moth(Citheronia sepulcralis), will emerge in spring from larvae that have eaten pine needles during summer and autumn, and then dropped to the soil underneath the tree to overwinter in a cocoon. https://commons.wikimedia.org/wiki/Citheronia_sepulcralis#/media/File:Citheronia_sepulcralis_male_sjh.jpg