ARBORETUM NEWS (NATURALISTSNOTES)

Red Lanterns

SUNDAY, OCTOBER 9, 2011

A funny thing happened on the way to this year’s “Red Lanterns” tour. I looked at my notes for the same tour last year, when it took place on October 10. My lead sentence was “How often is it 80° F. on an October afternoon?”
I could have begun this report pretty much the same way. The high temperature the day of the 2011 “Red Lanterns” walk was 78 degrees. Call it global warming or call it happy coincidence, but either way, it was a lovely day for a stroll out in nature.
We name this annual tour for an essay by Aldo Leopold. Featured in the month of October in A Sand County Almanac, “Red Lanterns” is about partridge hunting, and blackberry bushes. Leopold writes of going hunting with his dog, and wandering from one “red lantern” (blackberry bramble in fall glory) to another, in search of partridges. In fact, halfway through the essay he switches his target to grouse. I never noticed that before. How very odd.
Partridges and grouse are not the same thing. Gray, or Hungarian, partridge is a grassland bird, introduced to this continent from Eurasia; ruffed grouse is a native species which lives in wooded habitat. Both are in the family Phasianidae, which also includes pheasants and junglefowl. There are still hunting seasons for both partridges and grouse in Wisconsin.
For the purposes of the Arboretum walk, I do not limit the “red lantern” context to blackberries, but rather include all of the tree, shrub, and vine species which illuminate the landscape with red color at this time of year. And the West Curtis Prairie is positively glowing with sumac right now, so I set that as our destination.
Grasshoppers leaped out from underfoot as we walked along the firelane. Although there are over 70 species of grasshoppers in Wisconsin, the huge majority of the ones we see can be attributed to 3 species: Chorthippus curtipennis, the marsh meadow grasshopper; Dissosteira carolina, the Carolina duster; and Melanoplus femurrubrum, the red-legged grasshopper.
Prof. Charles Bomar of the University of Wisconsin-Stout, and Kathryn Kirk of the Wisconsin DNR, have written a book titled A Guide to the Grasshoppers of Wisconsin. They divide our grasshoppers into three groups, differentiated by observable physical attributes: “spurred throats, slanted faces, and banded wings”.
Trouble is, the only one of these which is a good field mark is the last one – banded wings, of which the Carolina duster is a familiar example. You have all seen these creatures. As they leap away, you see a flash of dark-brown wings, with a pale cream-colored band at the bottom. The other two features – the “spurred throat”, a tiny Adam’s-apple-like structure, and the “slanted face”, meaning a head angled so as to be almost cone-shaped – are not generally visible at the speed most grasshoppers travel. One would have to capture and pin the specimen to observe these traits. But it is a catchy set of phrases, and fun to know!
What grasshoppers are busy doing right now is their last-minute mating and egg production. The eggs will be buried in the prairie soil to overwinter; no adult grasshoppers will survive the winter.
But these notes were supposed to be about red lanterns. The first and most obvious one we saw was smooth sumac, Rhus glabra. There are great clumps of it in the western part of the Curtis Prairie – in fact, it has taken over more of the prairie than some of us would prefer. But at this time of year it is lovely, particularly when its scarlet leaves are backlit by the sun, as they were for our afternoon walk. The narrow trail between C-1 and C-6 is especially spectacular.
The other species of sumac which the Arboretum hosts in quantity is staghorn, or Rhus typhina. I have made an informal observation – not backed by solid science – that the leaves of staghorn sumac are more orange-y than those of smooth. Of course, Mother Nature loves to blur the rules, and the two species can hybridize, producing intermediate forms of both leaf and fruit. But if you see a patch of sumac which is brilliant blaze-orange, I think you will find that it is staghorn. Look at the younger twigs – they’re covered with velvety hairs, like new antlers on a buck.
Even gray dogwood (Cornus racemosa) can count as a “red lantern” in the proper light. Its leaves vary from pinkish to burgundy in October, but again, sunlight shining through them makes them glow. And we saw two vines that qualified, as well: Virginia creeper a/k/a woodbine (Parthenocissus quinquefolia), and poison ivy (Toxicodendron radicans). Just south of marker C-3, there is a spot where you can look west into the pine woods and see Virginia creeper on one tree and poison ivy on its immediate neighbor. Both are scarlet-colored. If you’re not sure which is which, don’t touch!
We paused to inspect the witch hazel specimen that grows just west of the Jackson Oak. I have just written about Hamamelis virginiana for the November NewsLeaf, so will not repeat that information here. Suffice it to say that we found cone-shaped galls indicating the presence of aphids, and flower buds for the blossoms that will appear in about a month. You read that right – witch hazel blooms in November, for heaven’s sake.
Returning toward the Visitor Center on the firelane, we encountered a woolly bear caterpillar. These larvae will overwinter in this form, i.e. not in a cocoon or chrysalis. That is why they are covered with “fur” (the proper word for the coarse hairs is setae). Folk wisdom says, inaccurately, that one can predict the severity of the coming winter by the proportion of black to brown in the woolly bear’s coat.
This one was not moving and I feared it was dead; but I picked it up, using a grape leaf since the bristles can irritate your skin, and it immediately curled into a circle. I set it down off the footpath, hoping this improved its chances of surviving until next spring. If it does, it will pupate and become an Isabella tiger-moth.
A “mystery shrub” found along the Curtis firelane is a mystery no longer! It’s another sumac – fragrant, or Rhus aromatica. I had not known of its presence there previously. It has three wavy-margined leaflets, and is turning a lovely pinkish-orange color for fall. Look for it west of marker C-1.
Bittersweet has begun to produce berries. These are rich red-orange with a yellow husk. Unfortunately, the specimen we saw was the introduced Oriental bittersweet, which is invasive. Whether native or alien, the berries are toxic.
We stopped at Margaret’s Council Ring, near the parking lot, to admire a bottle gentian still in bloom. There are a few remaining along the remnant prairie trail as well. Treat your eyes to these cobalt-blue treasures.
As a closing for the tour, I read Helen Hunt Jackson’s poem “October’s Bright Blue Weather”. It mentions so many of the same sights we had taken in: goldenrod, grapes, gentians, woodbine, winged seeds, and bright-colored leaves. As I read, three red-tailed hawks circled and called high above us, their rusty tail feathers perhaps the final “red lantern” of the day. Keeeer! Wherever you walk this autumn, may lanterns guide your steps.

Kathy Miner, Arboretum Naturalist

Located between Lake Wingra and the West Beltline Highway at 1207 Seminole Highway, the University of Wisconsin-Madison Arboretum features the restored prairies, forests and wetlands of pre-settlement Wisconsin. This 1,260-acre arboretum also houses flowering trees, shrubs and a world-famous lilac collection. Educational tours for groups and the general public, science and nature-based classes for all ages and abilities, and a wide variety of volunteer opportunities for groups, families and individuals are available.