Soft maples deserve respect, too
If you’re graceful, tall, and beautiful, you’ve got a lot going for you. If you’re breathtakingly beautiful in fall colors, and if you’re the sweetest thing around come spring, all the better.
And if you’re a tree with this winning combination of features, you’re undoubtedly a maple. A hard maple that is — either sugar or black maple.
There are two other types of maples in our area that are not so blessed with glamour and charm. These are the soft maples — silver maple and boxelder. They get no accolades, and they’re often overlooked.
Boxelder
Right off the bat you may be confused at the mention of boxelder in the same breath as maples. You’re not alone. Most people raise their eyebrows at the suggestion of boxelder as a maple tree. Boxelder is indeed a maple. Like all maples, it belongs to the group, or genus, Acer. Boxelder’s scientific alias is Acer negundo.
The lowly boxelder is a weedy tree that pops up at the edge of driveways, in old parking lots, and along every creek in the Fox Valley. It’s gangly, often growing several boles, or main stems. Its leaves are not like other maples — in fact, they’re dead-ringers for poison-ivy leaves in the summer. Fall color is zilch. In the spring, boxelders produce prodigious amounts of seeds — scads of which accumulate stubbornly on driveways and sidewalks. The stems, though, are pretty cool. They are a unique purplish-green-brown color, with a glaucous, or waxy, covering that you can rub off with your finger.
In its natural habitat, the boxelder is actually remarkable. It’s a pioneer species, well adapted to growing in harsh conditions. Its wind-born “helicopters” are fruit called samaras — another feature shared by all maples. Samaras are essentially seeds with wings on them that carry them twirling through the air. Thus transported on the breeze, boxelder seeds land in fields or on muddy banks of rivers after floods, and they are ready to go. They germinate rapidly to gain a foothold in the mud. Boxelder seeds are ripe for a long period of time, from August to October. The extended germination period allows the species to colonize disturbed areas throughout the growing season. Adding to this readiness, lots of boxelder seeds remain on the tree throughout the year.
In the spring, boxelder weeps. Not necessarily because no one likes it. It weeps because it’s a maple full of sap like other maples in spring. Any nick or cut in the tree will turn on the faucet. The profuse sap that exudes from boxelder can be collected and boiled down to syrup, just like that of sugar maple. It will take a heck of a lot longer, though, because the sugar is lower than that of sugar maple. Instead of 40 gallons of sap to make 1 gallon of syrup from sugar maples, it takes about 80 gallons of boxelder sap to create 1 gallon of syrup.
Though no great shakes in woodworking, boxelder can be used to make barrels and inexpensive furniture. It’s also used in carving. A species of fungus specific to boxelder causes red streaks in the wood, and the resulting “spalted boxelder” makes attractive bowls, vases and other works of art.
Boxelder gets a bad rap for its aggressive weediness, its prolific seeds, and its relative lack of timber value. But the main reason for its bad reputation is due to its close association with the infamous boxelder bug. These black and red insects are especially numerous after a long, hot, and dry summer. They invade buildings in the fall, looking for a cozy place to hang out during the winter months. When they break their dormancy, boxelder bugs emerge in droves — inside the house. They cause no damage indoors and are merely a nuisance. Outdoors, adults feed on the seeds and leaves of boxelder trees, and lay their eggs inside the tree. The insects are intimately dependent on boxelders. Hence, boxelder trees equal boxelder bugs.
Silver maple
Silver maple (Acer saccharinum) fares a little better than boxelder on the popularity charts. It’s the quintessential floodplain tree, able to withstand the high waters of spring and torrential rains that cause the river to flood its banks.
Silver maple trees grow big and relatively fast, and there are some really big individuals along the Fox River. As floodplain trees, they provide great habitat for birds migrating along the river corridor. The big trunks of silver maples tend to split down the middle with age. Not the best species to use in landscaping, but a fine species in their native habitat. Once a big silver maple splits, new habitat is created for cavity-nesting birds and mammals.
As for its foliage, the silver maple is no great shakes. The leaves are slender, light green on top and silvery on the bottom. They turn a lackluster greenish-yellow color in the fall, paling in comparison to their other hard maple kin.
On the plus side, the buds of silver maples are a harbinger of spring. They begin to swell in late February, when the snow still flies. Silver maples buds are a primary food source for squirrels in spring. Fortunately, many buds escape the squirrel’s grasp, and these buds soon produce flowers.
By March the flowers open — tiny yellow flowers high up in the tree. They are in bloom now, but you’ll need binoculars to see them. They are small, inconspicuous yellow flowers high in the branches — and they lack petals altogether. The wind carries their pollen in a matter of a week or so, and the pollinated female flowers produce “helicopters” (samaras) in early spring.
Silver maple samaras are distinct. They are the largest of all the maple samaras. The wings of silver maple samaras are thin and papery, as “daintily meshed as dragonflies’ wings,” in the words of Donald Culross Peattie, author of “A Natural History of Trees.” Similar to boxelder, the seeds of silver maple can germinate almost immediately upon landing on the rich alluvial soils of the river’s edge.
Silver maple is cut and sold as “soft maple,” but its wood is moderately hard and dense (the categories “soft” and “hard” are arbitrary, at best). Woodworkers use silver maple for basketry, furniture, and dyes. According to the Natural Resources Conservation Service, Native Americans found medicinal uses in silver maple, including “coughs, cramps, dysentery, sore eyes, measles, diuretics, and venereal diseases.”
Silver maple sap, like sap of other species of maples, contains sugar and can be used in syrup making. Its sugar content is significantly lower, however, so it takes more raw sap to make syrup. An up-and-coming use for silver maple may be in the biofuel industry in the Midwest.
Valerie Blaine is a naturalist with the Forest Preserve District of Kane County. She welcomes your feedback, comments, and questions. Contact her at blainevalerie@kaneforest.com.
Want to learn more about trees?
Illinois may be known as the Prairie State, but weve got some awesome trees as well as grasses. You can help discover and document the giant trees of Kane County as part of the Illinois Big Tree Registry. This statewide program encourages citizens to record and report the largest native trees. Learn how to get involved during this workshop led by Jay Hayek, extension specialist forester with the University of Illinois. This program for adults will be held from noon to 4 p.m. Saturday, March 30, at Creek Bend Nature Center at LeRoy Oakes in St. Charles. The workshop will begin with approximately one hour of classroom instruction covering tree identification, the history of the Big Tree program, and citizen involvement. Hayek will then lead an outdoor training on tree measurement and protocols for nominating big trees. The fee is $15 per person. To register, call (847) 741-8350 or email programs@kaneforest.com.