Northland Nature: Acorns are among tree leaves of late SeptemberLate September is a marvelous time in which we witness the autumn moving in at a faster pace.
Late September is a marvelous time in which we witness the autumn moving in at a faster pace.
The migration of raptors continues as these birds channel down the North Shore, passing over us as they continue to the south. Each day we hear loud flocks of geese also on migration movements.
And in our yards, we see that songbirds come by as well. Blue jays, robins and cedar waxwings form groups that stop to feed as they travel. I have noticed that the warbler waves are harder to find now, but these little birds are replaced by another, sparrows.
Indeed, the end of September and early October may be the best time of the whole year to observe diversity with these little brown birds.
Chipmunks and squirrels scamper about the yard and woods as they make food caches in preparation for the cold. Beavers gather food of branches to be taken to the lodge. Frogs, toads, salamanders and snakes are doing a migration of their own as they head for a wintering site. Insects that will soon meet their demise in the frosts are laying eggs in the ground and other protected locations.
Despite all this activity in the world of animals, we may see the biggest changes in the trees. As a scheme of these woody plants to survive winter, they will drop their leaves. (Apparently, flat broad leaves would cause the trees to lose too much moisture during the arid days of winter. They could die of desiccation and so, they drop the leaves.)
This survival technique happens over weeks in the fall and is accompanied by a dazzling display of colors. I find that this colorful show is done in several phases, the first of which is now.
This is the time when the scarlet-reds are presented by sumac, dogwood, cherry, red oak, red maple and the vine Virginia creeper.
Yellows far outnumber reds and the woods is full of sugar maples (often holding red-orange colors too), ash, basswood, birch, poplar, willows, elm, elder and hazel. These yellows blend in with the reds and oranges and they caused us to look and stop and look again. No wonder this time
is sometimes called “peak week.”
While looking among the colorful leaves, we may see that much more is going on with the trees.
Apples, crab apples, hawthorns, highbush cranberries and sumacs all carry ripe fruits and berries with the foliage. Sugar and mountain maples are loaded with seeds of a different kind, a winged type, called samaras.
And then there are trees that produce nut crops. Walnuts and hickories are more to the south of us while ours are hazelnuts and acorns.
Hazelnuts are frequently seen as they develop in summer, but I’ve noticed that by the time they ripen on these small trees, they are usually gone, taken by squirrels, chipmunks and bears.
Acorns, higher on the oak trees, are likely to last longer.
Each morning lately, I step outside in the calm cool conditions and hear the light thud sound as acorns fall to the ground. Some could be the ripened ones dropping from the stem, but often it is the work of squirrels as they bite the acorn stems and cause the nuts to drop — more food for their caches.
In my area, red oaks (correctly called northern red oaks) are very common and we are enjoying an autumn with numerous acorns. At our latitude, these large and long-lived trees will produce a mature nut crop every two years. Last year at this time, I looked out at oaks trees in the yard that were filled with tiny remnants of what I see now.
Though oaks are a diverse and widespread group with dozens of species found throughout the country, especially in the south, the Northland is home to only two kinds, the northern red oak and bur oak. (A little further to the south and west of here, we may find two more, the pin oak and white oak.)
Our local oaks are very easy to discern. Red oak is far more abundant than bur oak. The leaves of this large tree are deeply cut with lobes holding sharp points on the edge. Acorns are robust with small caps. I find that some, usually the smaller ones, will live up to the name and turn a bright red in fall.
Bur oak also has the deep cuts but the lobes are rounded. It is the large bur-like cap of the acorn that gives the tree its name. Leaves are yellow in fall.
Acorns of both are foods eaten by many of our wildlife. But for us, the oaks and their acorns provide just more of the forest delights of this time of fall.
There’s more among the dazzling leaves of autumn.
Retired teacher Larry Weber of Carlton is the author of several books, including “Butterflies of the North Woods,” “Spiders of the North Woods” and “Webwood.” You may contact him at firstname.lastname@example.org.