Peterson Lake Trail

slime molds, a berry cornucopia, and a beautiful poison

One bright, sunshiny day in mid August, we checked out the Peterson Lake trail, which is about four and a half miles long, and ends at cabin by the lake. There were rumors of recent trail improvements on the first three quarters of a mile. Indeed, there’s a section with a new base layer of angular, ankle-twisting cobbles, eventually to be covered by finer gravels; then there’s a section of packed dirt and, just before the big waterfall, a smooth section of finished trail.

After the big waterfall (where the steelhead have to stop, in the spring), the trails goes on as it has for years, with a section of packed dirt and slippery ‘corduroy’ logs and then boardwalks through the muskegs. At the Mile 2 marker, a long stretch of mud and roots winds through the forest until the lake finally appears.

The forest was very quiet on this day and no birds were evident, so those of us who are interested in natural history focused nearer the ground. A black slime mold had developed on a log: thousands of individual, independent cells had been feeding on bacteria and fungi in the soil, but now they had gathered together in a single mass for reproduction. Some of the cells will produce spores, while others serve as support structures for the spore-producing individuals. I wonder how they decide which cells will make spores!

The muskegs were dotted with several kinds of ripe berries, including black crowberries, bog blueberries, red bunchberries, and orange cloudberries. I was interested to find a large colony of timberberry in one of the muskegs, with several stems bearing the orange fruit. Timberberry is sometimes called pumpkin berry or, for no apparent reason, bastard toadflax—a name more correctly applied to a different species, but still for no known reason. The name game gets quite confusing, because this plant had been classified in two different genera at different times by different taxonomists. Sigh. The most interesting thing about this plant is that it is a hemi-parasite, drawing some of its nutrition from other plants while also having its own leaves. This is a very versatile parasite, capable of using many host species, such as spruce, alder, willow, currant, bunchberry, horsetail, asters, lupines, and dozens of others.

timberberry--2-David
timberberry. Photo by David Bergeson

The lake level seems to be maintained in part by beaver dams at the outlet. After poisoning many of the resident fish some decades ago, the lake was stocked with juvenile rainbow trout (in the 1960s). A boat by the cabin gives ready access to all parts of the lake.

Along the trail, we noted several late-flowering monkshoods, one of our loveliest wildflowers, which grows at many elevations around Juneau. The complex, bumblebee-pollinated flower is usually a rich purple, although sometimes the purple is streaked with white. A fascinating feature of this plant is that ALL parts are reported to be very poisonous, but perhaps especially the roots and seeds. Eating even a tiny amount of this plant is likely to cause intense gastro-intestinal distress, followed by cardiac and respiratory failure if not treated immediately. And if you handle the plant more than casually, for example by picking leaves or breaking off the stems with your bare hands (not merely brushing by it as you walk), your skin can absorb the poisons. You are then likely to suffer the negative cardiac and respiratory symptoms, but without the gastrointestinal calamities.

The poisonous properties of monkshood have been known for centuries, and extracts of the plant have been used to make poisonous arrows for hunting or warfare, among other deadly uses. On the other hand, as is true of many plant poisons (think of digitalis, for instance), monkshood has also been used medicinally, in small, careful doses. It is a food plant for the caterpillars of several species of moth, which clearly have evolved physiological means of dealing with the poisons. And the bumblebees that pollinate the flowers either find a way to cope or else perhaps the nectar and pollen has less of the poison. Monkshoods are popular garden plants, but it is obvious that gardeners must handle this plant with great care!

Benjamin and North Islands, part 2 of 2

profitable prowlings

One of the special treats of our little excursion to Benjamin and North islands was finding ourselves comfortable in shirtsleeves—no jacket needed, even when crawling out of our tents at six in the morning. How often is it that warm in Juneau!?

In addition to enjoying the marine wildlife, we wandered around on both islands, just exploring. We saw one young deer, with a beautiful summer coat of red, and lots of deer sign. Deer had cropped the leaves of false lily of the valley, occasional stems of twisted stalk, and most of the leaves from sapling crabapple trees. A little stand of skunk cabbage had been reduced to ragged nubbins. Fresh water seems to be in short supply, particularly on North Island, so we wondered how deer would get enough water.

We also found skeletal evidence of four long-dead deer, some apparently quite young, leading us to speculate about hard winters in these sites. Two lower jaw bones caused us to query ADFG when we returned. One of the mandibles we found had four cheek (grinding) teeth in place plus a fifth one just erupting at the back of the jaw. A mature deer lower jaw holds six cheek teeth (three premolars and three molars), and the full set is in place at an age of about two and a half years. The jaw with the just-erupting fifth cheek tooth had belonged to a young deer, perhaps nine to twelve months old, according to ADFG.

The ground, in some places, was riddled with small holes, just the right size for a red squirrel, but we saw no evidence of current squirrel activity: No busy little fussbudgets chattering at us, no middens of stripped spruce cones, and many of the holes had spider webs across the opening. This year, there are huge numbers of spruce cones still on the trees, so food supply for squirrels should be quite decent. We wondered, then, if there had been squirrels here in the past, but perhaps a year or two of poor cone crops had wiped them out.

Among the rocks on the uplifted beach meadows we startled several good-sized voles, which scooted quickly into handy crevices. How did they get to these islands? They can certainly swim well, but it’s a long distance, for a vole, from the mainland to the islands.

As we stood quietly in a beach meadow with a dense population of lupines, we heard tiny tapping sounds and soon discovered the source: Mature lupine pods were explosively twisting open in the hot sun and the dispersing seeds clattered softly down through the surrounding vegetation. At the upper beach fringe, a stand of cow parsnip presented heads of closely packed clusters of maturing seeds. We were fascinated to observe that each little cluster of seeds resembled a rose, carved in wood. So the whole head was, so to speak, a bouquet of wooden roses. Beautiful!

Some very sturdy, squat plants lined the top of one beach, and bore yellow daisy-like blooms. These beach grounsels, with large, spreading leaves, are very specific to this particular habitat type. Each yellow ‘flower’ is really an inflorescence composed of a ring of showy flowers around a disc of many, small, not-showy flowers, altogether forming the daisy-like composite inflorescence. We noticed that ants were visiting the central flowers, presumably sipping nectar. What an odd place to find ants, which don’t seem to be common in Southeast.

On the forest floor were numerous evidences of predation: Three piles of crow feathers (and feet), plus a regurgitated pellet with an intact crow foot. Four piles of gull feathers. Scattered plates of chitons. Sea urchin tests (a.k.a. shells). Some clam shells and small crab legs. Eagles and otters, and perhaps others, had found their dinners.

Other sightings:

  • A row of extremely contorted spruces on a raised terrace well inside the present forest edge. What could be their history?
  • A dogwood bush, normally shrub-sized, but in this instance sending a long branch or two far up along a spruce trunk, almost like a vine. Apparently its only chance to reach the light was to straggle upward, because the dense thicket of young spruce at the forest edge effectively blocked light from shrub-level.
  • An orchid with vanishingly small flowers (with the regrettable name of adder’s mouth), presumably pollinated by insects as tiny as no-see-ums. Could those miserable pests actually have a use?
  • Several specimens of slime mold, growing on fallen logs. One kind was white and spongy, the other was yellow and fuzzy-looking. Spending most of their lives as separate cells in the forest floor, upon some unknown signal the cells come together to form the visible mold, and reproduce.
  • A family of Pacific/winter wrens in a heap of wind-thrown trees, the young ones curious, the parents wary.

From our perspective, our prowlings were profitable. These little explorations are like treasure hunts in which the treasure is unknown ahead of time but recognizable when one sees it.