Friday, November 23, 2018

Real-life Truffula Trees

“What do you miss the most about Alaska?” is a common question for me these days. It comes up so frequently in fact, that I added my answer to the end of the “Adventures in Alaska” slideshow I’ve been presenting at local venues. The answer? Avens.

I think that there is a good chance that Dr. Seuss was acquainted with the seed heads of avens before he illustrated The Lorax.  Photo by Emily Stone.

Mountain avens, entireleaf avens, and yellow dryas are all flowers in the genus Dryas whom I encountered frequently throughout Alaska. Their flowers are beautiful, with silky white or yellow petals and sunny yellow centers, and their habitats on tundra slopes and fields of glacial gravel are fun to explore. It’s their seed heads that captured my heart and my imagination, though.
Dryas octopetala, Mountain avens, Photo by Emily Stone
Dryas drummondii, Yellow dryas, Photo by Emily Stone.
Dryas integrifolia, Entireleaf avens. Photo by Emily Stone

Like an elegant dandelion, each of their many, small, dry, seeds comes with its own fuzzy parasol. As the seeds are maturing, those feathery styles spiral from silky, pink swirls into shimmering white fairy puffs. Truffula trees from Dr. Seuss’s The Lorax spring to mind immediately, and the fuzzy tufts also conjure images of Einstein’s signature hairdo. I delighted in taking photos of these amusing little beauties throughout my summer. Rain or shine, they brought me joy.

Dryas sp. Photo by Emily Stone

Dryas sp. unfurling, Photo by Emily Stone


Dryas sp. unfurling, Photo by Emily Stone


Even soggy Dryas seed heads are amusing! Photo by Emily Stone.

I didn’t start out to tell you all about avens, though. That just slipped in. This is actually a story about a mystery plant that a Museum member brought me a photo of last week. Taken of the shrubs in a soggy road ditch, her focus was on some curious, spikey clusters that decorated the slender twigs. “Avens tree,” she had labeled the photos, and wanted not only an identification, but to feed my obsession clearly evident above.

Even willows growing in wet ditches in Wisconsin can have delightful seed heads. Photo by Emily Stone.


The photo confused me. Avens doesn’t grow in Wisconsin. The only Dryas here was the Younger Dryas, a period of colder temperatures 12,900 to 11,700 years before present. It was the last hurrah of the glaciers, and it’s named after the abundance of Dryas flowers preserved in Scandinavian lake sediments of that age.

Insect galls? Clematis? What could these be? But when Vivianne brought a sample into the Museum, one look at the slender, orangey twig and single, dark purplish scale covering each bud told me it was a willow. The fluffy, avens-like baubles she’d noticed are simply their dried out catkins with fuzzy seeds still clinging on. Of course. The willow family—Salicaceae—also contains cottonwoods.

We can easily imagine willows being fuzzy in the spring, as their catkins expand and the fine, gray hairs protecting their emerging flowers form the phenomenon we think of as pussy willows. After bees have pollinated those flowers while greedily making use of one of the earliest sources of pollen and nectar, the plant begins to develop seeds.


  
Cottonwoods use wind instead of bees to pollinate their flowers, but the result is very similar: both cottonwoods and willows produce Lilliputian seeds attended by downy, flight-ready fluff. Cottonwood seeds—and the related aspen and poplar seeds, too—are hard to miss when they create summer snowdrifts on your lawn. While many allergy sufferers grumble during this phase, the fluff is not the cause of allergies—the pollen that created those seeds was the problem.

I’m not sure why we so rarely notice the second fuzzy stage of willows around here. My standard response to having missed any late spring or early summer phenomenon is that it must have happened during mosquito season, when I don’t spend much time walking slowly through the woods.

Happily, since my summer in Alaska lacked both mosquitoes and a bicycle, I had ample opportunity to hike among wildflowers in all their stages of development. Willows are common on the tundra, and several of the fourteen Salix species that grow in Denali National Park are delightfully tiny, easy to observe at eye-level if you’re willing to belly-crawl (which, of course, I am). For example, netleaf willow grows as a creeping shrub. Its deeply embossed leaves are a normal size, but it doesn’t grow more than a few inches high. Its catkins are actually larger than those of pussy willows, and stick jauntily upright.






By late August when I traveled up to the tundra on the North Slope of Alaska, I was able to enjoy both the lemony yellow fall colors of willow leaves as well as the fuzzy fingers of their catkins gone to seed.




A few of Vivianne’s funny little willow catkins are still floating around my office, and they’re reminding me that avens-like delight can be found right here at home.


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Emily was in Alaska for the summer. Follow the journey in this column, and see additional stories and photos on her blog: http://cablemuseum.org/connect/.


For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: “Bee Amazed!” is open.

1 comment:

  1. Thank you for this lovely article. I enjoy them all and also rereading your book through the seasons. I can't wait to get the next one

    ReplyDelete