Out on the Ice to the Islands Again

Since I offered to lead my friends in the Thursday Naturalists out to the islands of Lake Bonita this week, I went there today to preview the walk and search for points of interest.  As this lovely little lake is now part of Moreau Lake State Park, the park has created a large (plowed!) parking area off of Corinth Mountain Road, with a trail that circles the lake leading off of the parking lot.

It's quite a long descent from the parking lot to the lake, but the trail takes a meandering path across the slope so that it never seems too steep for folks of limited agility to manage.  The trail is definitely icy, though, and should not be attempted without some kind of ice grippers on your feet.  I wore my microspikes today and carried a hiking pole, so I never felt in danger of slipping.

A remarkable feature of Lake Bonita is the abundance of little islands, each covered thickly with shrubs as well as a marvelous array of plants we usually associate with bogs or fens.  Since the park has forbidden the use of boats on this pristine lake, the only time we can carefully search these islands for their botanical treasures is when the lake is solidly frozen.  As it certainly is right now.

The most abundant plants on these islands are the woody shrubs, primarily Leatherleaf, Sweet Gale, and Sheep Laurel, underlaid by a marvelous variety of sphagnum mosses and herbaceous acid-tolerant plants like Pitcher Plants, sundews, and native cranberries.  Although most of the lower-growing plants are now hidden under several inches of snow and ice, the shrubs, of course, are easy to find and fun to try to identify.  These gracefully arcing twigs still thick with leathery leaves are those of the shrub called Leatherleaf (Chamaedaphne calyculata).

Many of the Leatherleaf shrubs bear the exploded seed pods of what had been small, white, bell-shaped flowers.  A close look reveals that these husks are almost as pretty as the flowers were.

Sweet Gale (Myrica gale) is the second most common shrub on these islands, and its twigs are now adorned with the cone-like buds of next spring's flowers. I think these buds are quite elegant, with each shining brown scale outlined in pale ivory.

Some of the Sweet Gale shrubs (the female ones) now bear these spiky little seed pods.

A pinch of those spiky seed pods sends a shower of seeds to the snow below, and also delivers a delicious spicy scent to your fingertips.  There's a good reason this shrub has "sweet" as part of its common name.

Here's the third most common shrub of the islands, Sheep Laurel (Kalmia angustifolia), which can be distinguished from other bog-dwelling laurels by the terminal cluster of leaves surmounting the flower cluster.  This shrub, which has bright-pink flowers in late spring, also has leaves that retain much of their rosy autumn color throughout the winter.

A few small trees protrude above the shrubbery, the most common being Speckled Alder (Alnus incana).  The alder's branches are already hung with male catkins that will open to shed their pollen in spring.  The female flowers (now in tight reddish buds that dangle above the catkins) will open a bit later to receive pollen from neighboring shrubs.

Some of the alders bore these curly brown tufts, galls that are caused by Taphrina alni, a fungal plant pathogen that affects just the female flowers of alders.

The willowy stems of Swamp Loosestrife (Decodon verticillatus) still bore the remains of its axillary flower clusters, which in summer are a pretty bright purple.

When I find the persistent stems and flower bracts of Meadowsweet (Spiraea alba var. latifolia) throughout the winter, I am reminded that this lovely summer flower is indeed a woody shrub and not a tender herbaceous plant. It grows abundantly out on Bonita's islands, as well as along the shore.

The same is true for Steeplebush (Spiraea tomentosa), whose winter remnants can frequently be found along the frozen shore of Lake Bonita.

One of the most common sedges to be found in  northern bogs and fens is White Beak Sedge (Rhynchospora alba), and it, too, can be found on the boggy islands of Lake Bonita. Its persistent slender stalks are still easy to find waving in the winter wind.

The Northern Pitcher Plant is one of the most emblematic plants of northern bogs and fens, and this plant appears to be very happy growing on Bonita's islands.  Although its distinctive tubular leaves are now buried beneath the snow, its spent flower stalks still ride high above the drifts.

Here's a photo of those colorful "pitchers" I took last summer, when I had special permission to paddle out to Bonita's islands for the purpose of conducting a plant survey for the state park.  Note, too, the gorgeously colorful sphagnum moss, as well as the pink-veined green leaves of Marsh St. Johnswort and the tiny trailing leaves of Small Cranberry.  There's even a tiny Round-leaved Sundew plant in the center foreground, if you look carefully.

Although many of the herbaceous plants do not produce persistent remnants, the tulip-shaped seed pods of Marsh St. Johnswort (Hypericum virginicum) can still be found protruding above the snow.

Many mint-family plants also have stems and seed clusters that persist through the winter.  This group of slender stalks strung with axillary clusters could be one of several mints.  If I had to guess, I would bet it was one of the Lycopus species (Water Horehound or Northern Bugleweed), or possibly Wild Mint (Mentha arvensis). Some of these mints are hard to distinguish even when they are in bloom.

Hmmm. . . .  What flower could these pod-topped stalks be the remnants of?  I confess I have never seen them before, at least in this stage of their life.

When I recall what was growing here last summer, I remember the slender stalks of Horned Bladderwort (Utricularia cornuta), which were topped with clusters of several blooms.  It's certainly possible that's what those unknown flower stalks could be.

Update:  I received a note from Michigan naturalist Ron Gamble, who confirmed my guess that these flower stalks were those of Horned Bladderwort.  Ron provided a link to Michigan Flora Online, where I found this photo of Horned Bladderwort seed capsules  Sure looks like a match to me!  Thanks, Ron! (Photo by G.E. Crow)

Quite a few of summer's plants remain hidden beneath the snow now, but on the other hand, some things that were hidden in summer are now revealed in winter.   This bird's nest tucked in among the twigs of Sweet Gale and Alder was well-hidden when the shrubs were leafed out and the mother bird (a Red-winged Blackbird?) was sitting on her eggs.

As the day grew late and snow clouds moved in, I reluctantly turned toward home.  I would have loved to just continue walking around Lake Bonita's rocky and forested shoreline, enjoying the silence and solitude of this beautiful place. How lucky we are that its acquisition by Moreau Lake State Park has made it accessible to the public.  When Lake Bonita and the surrounding acres of forest were part of the Mt. McGregor State Prison property, it would have been illegal for me, or any other unauthorized person, to explore this property's remarkable ecology.

As I approached the break in the shoreline trees that would lead me back to my car, I was pleasantly jolted by this vividly colored Highbush Blueberry shrub. My eyes had grown accustomed to the muted hues of white snow, gray sky, and brown foliage, and I found the bright-red of these buds and twigs, backed by the emerald green of shoreline conifers, quite astonishing and wonderful.