The Marion Natural History Museum is a place of learning for all ages. With programming suited for children and those who were once children, opportunities abound for scientific exploration of the world right outside our door. And so it was on February 15 in Marion’s own Washburn Park where Museum Director Liz Leidhold introduced a group of knowledge seekers to James Rassman, Southeast District service forester from the Massachusetts Bureau of Forestry, eager to hear him speak on the topic of tree identification during winter months.
Rassman told the group that he primarily works with private landholders as they make critical decisions about their woodlands. A quick look at the University of Massachusetts Amherst website informs us that some 62% of the state is forested, that Massachusetts is the eighth-most-heavily forested state in the country in spite of being the third-most-densely populated.
“Our lives are intimately linked to the health of our forests,” said Rassman. “Two hundred and twelve thousand private landowners in the state own 75% of all forests (in Massachusetts.)”
But we were there to learn a bit about how to identify trees in their natural habitat – woodlands.
We kept running into facts about how humans have modified plant life and the very topography of the land through cultivation and harvesting trees over the centuries.
Rassman said that as far back as the early colonization of the area, trees have played a critical role. Beyond the obvious need of wood for building shelters and staying warm, kings set their sights on our tall native White Pines used for spars. Rassman said that England had basically depleted its tree populations over centuries of human activity, thus when the colonists reported the abundance of tall straight pines, the King claimed them for sovereign use. A stamp was marked into those trees headed for harvest and deportation to England for their ship-building needs.
Eastern White Pine can grow in a number of soil conditions and is easily the most important tree in the local woods, not just for lumber but also as home to many birds and small animals. Home, tree home.
Rassman pointed out identification targets such as the presence of five-needle clusters growing between 2 and 5 inches on these forest giants. The bark of young White Pines is thin and smooth, maturing to a dark gray-brown that is deeply fissured with ridges and deep indentations. Its “fruit” or pine cones are a mixture of both male and female (monoecious) from the same tree. Between May and June, male cones release pollen. Female cones can reach 8 inches in length. The cones ripen from green to brown before falling to the ground, heavy with seeds.
As for that thick yellow pollen that can be difficult to live with during the spring season, maybe we will now appreciate the drama of nature, the story of life as we clean the yellow film off our cars.
Of all the trees in our local forests, pines reign supreme; that includes the pitch pines, number two in the pine hit parade. This pine variety is not good for lumber and historically was used for making charcoal.
Before advancing further into our woods walk, Rassman pointed out notable landscape features. He said, “There aren’t any straight lines in nature.” The little, fast-moving stream along the former bog road trail we walked was an example of manmade irrigation systems. He also shared that the presence of lichen thickly layered on just about every type of vegetation is a good sign. “It doesn’t hurt the trees and only grows where there is good air quality.”
Rassman spent time describing how best to identify trees in winter where leaves might not be present to assist in the process. He explained how stem and branch placement can be used to help in the process, as well as where the trees are growing and sandy soils versus wet swampy locations.
Deciduous trees, the maples, oaks, dogwood, black gum, tupelo and others, may also be found in local woods and are considered native to the area. The leaf matter that blanketed the grounds we walked along told the story of last season, oaks with hair-like fibers at the end of each scalloped edge of the leaf and the delicate maples with a central point from which the tips fan out to reach the sun. (Sidenote: Oaks only grow where they can get ample sunlight, but pines are not so fussy.)
Here’s a telling statistic: The forests of Massachusetts contain a wide variety of tree species, with 82 species observed on the FIA plots inventoried between 2009 and 2013. In terms of total volume, Eastern White Pine is the most common species, but in terms of number of trees, red maple is the most common.
Rassman noted that due to heavy forestry activities and other manmade disturbances to the landscape, most pine forests range between 50 and 80 years old. Yes, there are still old-growth forests but not so much locally. Plymouth can claim one. And speaking of old-growth forests where we humans have surprisingly not disrupted nature, the museum will be hosting David Orwig, senior ecologist and forest ecologist for the Harvard Forest, to discuss old-growth forests in Massachusetts. That event will take place on Friday, March 31, at 7:00 pm at the museum. For more details on this and other programs planned for the community, visit marionmuseum.org.
Marion Natural History Museum
By Marilou Newell