ARBORETUM NEWS (NATURALISTSNOTES)

Autumn in Curtis Prairie

SUNDAY, SEPTEMBER 25, 2011

This rain paused and the sun even came out for a bit during Sunday afternoon’s walk. We “sampled” autumn in Curtis prairie, Teal pond, the Native Plant Garden, and everywhere in between. Bottle gentians (Gentiana andrewsii) are in bloom in Curtis (and also in the Native Plant Garden). There’s a lone plant (or perhaps more?) right by the A3 the fire lane T, and then many more throughout the trail crossing the remnant section of Curtis prairie. We admired the intense indigo blue of the flowers. We also saw a few plants of the white-flowered variety, although their flowers were mostly brown. Gentians aside, the prairie is still brightly colored with goldenrod yellows, aster purples/pinks/whites, and the many shades of autumn greens/browns/reds. We compared the common (or Canadian) goldenrod (Solidago canedensis) with grass-leaved goldenrod (formerly considered a Solidago, it is now classified in a different genus and is called Euthamia graminifolia). The grass-leaved goldenrod has small, narrow (“grassy”) leaves and tiny yellow heads within a flat-topped inflorescence. We also looked at stiff goldenrod (Solidago rigida), which does, indeed, have a stiff stem. It also has wide, rounded kitten-ear leaves, which (among other traits) distinguish this species from any other goldenrod.
In Teal pond, we observed a green heron perched on a branch at the edge of the pond, apparently intent on catching a bite to eat. These herons are known for their use of bait to attract fish, which they then capture with a quick flick of the beak. One visitor noted that there are some fun You Tube videos of green herons demonstrating their tool-use-while-fishing skills. We also saw some mallards, working hard at eating up the abundant duckweed. We noticed that the duckweed covered the water surface so thoroughly that there were many tiny insects walking across this new surface – not gliding across, as some do, but really just walking on the surface of the plant cover.
We walked out from Teal pond and around toward Longenecker gardens. Some of the sumac leaves are already brilliant red, there’s also yellows, oranges, and browns, but still mostly green throughout the trees. Inside the trees there’s lots of action in preparation for winter. Deciduous trees’ shedding of leaves (abscission) is a highly organized, controlled biological process. Changing ratios of different “competing” plant hormones help prepare the cells along the abscission layer, found at the base of the leaf petiole, where the leaf attaches. Hence, if you look at the petiole end of a fallen leaf, you see a “clean” break along this abscission layer. Walking through Longenecker we couldn’t resist a quick side trip to admire the spiky American chestnut fruits. They are WELL armed against predators!
Thanks to a visitor-extraordinaire for pointing out the perfect white globe of a puffball mushroom tucked under the brush (in front of the black locusts) as you walk up into the Native Plant Gardens. It has evidently been there for a couple/few weeks, but looks perfectly fresh (perhaps thanks to the cool weather?). These are edible, although rather flavorless, fungi. You can sometimes purchase a slice from a forager at the farmers market.
And finally, a mystery – a scatological mystery: We poked around a bit in what we thought was coyote scat (it seemed characteristically twisty and about the right dimensions) near the Teal pond path entry. And then we found it EVERYWHERE – on the trails, in the native plant garden, the parking lot, and beyond. It started looking not-so-coyote-like, but it was most certainly the same meal. We talked with Susan Carpenter, who also exclaimed about this scat, which she had found back by the service drive and buildings. Really, it was EVERYWHERE. Extraordinarily abundant. Susan thought that maybe it was raccoon scat and wondered what sort of wild dietary event preceded this show. Whatever it was, all of the individuals seem to have eaten a very similar meal, and that meal seems to have involved some sort of fruit, pieces of which were still visible but difficult to precisely identify. So be warned—when you come out this week to enjoy the beautiful autumn days at the Arb – watch your step!

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.