A property boundary often is marked by installation of a barbed wire fence -- something to keep cows in a pasture or a place where two or three horses run up to whinny their gentle greetings as we walk by. For many of us, I suppose, it's where we first tore our britches on a few strands of rusted wire when we were children.
As years pass, that old boundary fence becomes an ecologically important hedgerow, always fascinating if we examine its function and value to a living world of nature.
We might begin with the chipping sparrow who always lines her nest with horse hair. No matter how distant that nest may be, this little chipping sparrow comes to fetch that necessary nest material where it has been snagged in the barbed wire. The cows and horses never let this little bird down.
Soon a cardinal and a catbird get in the habit of flying to that boundary fence with berries they bring for lunch. Dropping seeds and quite a variety of fruit below their perch, all this visiting bird life will account for the many fruit-bearing trees and shrubs that begin to appear. The eventual alignment of a hedgerow will coincide with the fence where so many birds ate lunch.
Tangled thickets of vegetation now completely hide the old barbed wire. In this "pioneer stage," early settlers of the hedgerow will probably include a few expanding clumps of staghorn sumac, gray dogwood and choke cherry, which generally sprout in beds of blackberry and black-berried elder. Before long, mantles of summer grape and fox grape will sprawl across these thickets. Flame-red satin gleams from the bark of fast-growing pin cherry and streaks of silvery gray give us the telltale sign that shadbush has joined in this beginning of a hedgerow thicket.
Inevitably, such dense vegetation provides suitable cover for an abundance of birds soon found nesting here. At the four-foot level there may be a nest of yellow warblers or an occasional pair of indigo buntings. Perhaps these will be joined by cardinals, catbirds and even the mourning doves, for whom the grape vines afford ideal nest sites at a slightly higher level. A pair of song sparrows select shade for concealment of their grassy home at the base of a shrub.
Yet far more significant than its advantage to a bird population is the importance of this hedgerow in establishing a safe corridor of access, enabling certain forms of wildlife to move unseen from one woodlot to another. Among these will be ruffed grouse, chipmunks and the squirrels, which introduce the hardwoods -- nut trees like walnut, oaks and hickory -- planted along the route.
Nibbling among canes of blackberry indicate that cottontail rabbits seek refuge here in winter -- especially when a woodchuck provides a network of burrows under the protective cover of this hedgerow. A few clumps of burdock usually mark an entrance, a place where that marmot scratched off seed clusters carried home on its furry flanks. Again, it may have been a hungry fox, trotting along the hedgerow, which deposited the burdock in pursuit of a cottontail.
In the course of time, the hedgerow matures, advancing from a sun-loving "primary stage" to a more shade-tolerant "secondary stage." Black locusts and hawthorn have moved in, and giant black cherry trees replace the pin cherry. Eventually, the dairy farmer sells all his cattle; according to velopment
nature's design, all that open space of his pasture gradually closes in, reverting to forest.
A series of ownerships may bring about a shift of boundary lines, sometimes linking one property with another. An enormous sugar maple or age-old black cherry still serve as "boundary trees," lined up to describe the original hedgerow.
It's fun to tramp through the expanse of the Members' Refuge at Beaver Meadow or hike along the trails at Allenburg Bog or Deer Lick. From time to time, we step through an alignment of older trees, often a pure stand of black cherry, which tells us that these are the remnants of an ancient hedgerow now trapped within more recent growth of woodland.
Even if we don't carry a compass, there's really no need to get lost. Besides the fact that the sun never rises in the south or sets in the north, we can rely on the east-west stand of taller trees to indicate proper orientation with a former hedgerow and any boundary precisely surveyed to face east and west. When five or six major shoots mark the division of more recent growth, such suckers usually represent slashings to clear the way for a surveyor's transit. Even a few lengths of rusted barbed wire may further confirm the former existance of a boundary fence.