Observing Nature's Harvest
The arrival of fall in New England brings a dazzling array of colors as well as relief from summer’s heat. While you’re out on the trail enjoying the crisp air and relative lack of biting insects, look a little closer: you’ll see an important part of the seasonal cycle happening right before your eyes. It’s harvest time, not only for us but also for wildlife.
Autumn is an important time in the annual cycle. For many plants, late-summer and early-fall seed dispersal marks the climax of the growing season—the start of a new generation. Plants have numerous strategies for producing and spreading their seeds, and quite a few animals take advantage of this bounty.
The nutritious offering of seeds and fruits comes at just the right time for many species of wildlife as they look to fuel up for the challenges of winter or a long migration. For these animals, this period of preparation is a critical time in their yearly cycle. Additionally, those “leftovers” they overlook in the fall will provide a larder for the fruit- and seed-eating species that are active all winter.
Here are some examples of nature’s harvest that you can look for while out on the trail this fall.
Berries & Other Tasty Fruits
One strategy of seed dispersal is to offer an attractive package of food to passing animals. It’s a win-win strategy: the animals receive energy and nutrients, while the plant’s seeds are deposited in a new location along with a dose of fertilizer. Plants that use this strategy include cherries, cranberries, grapes, bayberries, and elderberries, as well as roses, which produce rose “hips”—enticing fruits formed from the rose flower after it has been pollinated. The bright colors of all of these ripened fruits advertise to birds and other wildlife that they are ready to be eaten.
We humans also enjoy some of these examples of nature’s harvest. If you do sample these treats, please remember that you are sharing with the wildlife around you, so don’t take too much. Additionally, always be sure of a fruit’s identification and edibility before eating it. Here’s one treat for wildlife that is off-limits to us: poison ivy berries. While most of us must carefully avoid poison ivy, animals such as woodpeckers, warblers, vireos, deer, bear, muskrats, and rabbits freely eat these berries.
Nuts & Seeds
Nuts and seeds are also tasty morsels for wildlife. In these cases, the nutrition in the “package” is intended to provide fuel to the developing seed, not the animals that eat them. Animals that digest nuts and seeds incompletely or fail to return to where they cached them allow some seeds to survive their encounter and sprout the following year.
Oak, hickory, beech, and walnut trees are important nut producers, while pine and maple trees as well as grasses produce large quantities of seeds. You might see turkeys passing grass seed heads through their beaks, stripping off and swallowing the ripe seeds.
Nuts are an important food source for large animals such as bear and deer. Many species of smaller wildlife, including squirrels, chipmunks, raccoons, turkeys, blue jays, crows, ruffed grouse, and wood ducks, also depend heavily on nuts in the fall.
Collectively, nuts and seeds are called hard mast. The abundance of hard mast rises and falls in irregular cycles. We have all likely experienced those autumns in which the oak trees produce so many nuts it seems we could take a surfboard and just roll across the forest floor on a sea of acorns. The exact causes for this are not well understood, but it does appear that this habit benefits nut-producing tree species by overwhelming nut-eaters at unpredictable times and ensuring that more seeds will survive and germinate.
Bark & Twigs
Our last category of nature’s harvest is a bit different. You may see signs of browsing on twigs and bark, primarily by deer, rabbits, and rodents. In this case the animal is taking part of the plant without returning any benefit, except perhaps a good pruning.
Buds have reached maximum development in the fall. Within them are next year’s leaves or flowers, ready to burst forth when the warm weather and plentiful moisture return in spring, and they represent a nutritious morsel for browsing animals. Bark carries nutrients in the layer just below the surface, and is always there for the taking in winter when other foods are scarce. You may find twigs missing their end buds or bark scraped from trees as evidence of this activity.
See how many examples of nature’s harvest you can find on your walks this autumn!
This article is was featured in the Fall 2017 issue of Explore, Mass Audubon's quarterly member newsletter.