Canal Park at Lock 4 on the Hudson River
Thursday morning dawned cold and windy, but that kind of weather did not daunt my dedicated naturalist friends, especially when we have such a rich site to explore as Canal Park at Lock 4. This park is in Rensselaer County, just across the Hudson River from Stillwater and bounded on two sides by both the Hudson and the Hoosic. We hadn't gone more than a few yards into the woods when we came upon some Deerberry shrubs, a blueberry relative but one that's a lot less common than the ubiquitous lowbush blueberries we see everywhere. Most of the distinctive flowers had already dropped, but here we are searching to find the few that remained.
We were making a beeline (well, as much of a beeline as botanizers ever make) through the woods to reach a low floodplain site on the Hoosic River, where seasonal flooding delivers the enriching silt that enables a fascinating variety of plants to grow.
We had a particular plant in mind, one we had found just a single (rather puny) specimen of three years ago, and this year we were hoping we might be able to find it again, and hopefully find it in bloom. And boy, did we ever! The plant is called Green Dragon (Arisaema dracontium), and none of us had ever seen it growing in such abundance and to such enormous size as we did this day on the banks of the Hoosic. And all of them were in perfect bloom! (That's the flower, that spindly curving golden spadix protruding from the green spathe that has sprouted from the stout stem.)
We counted dozens of plants today, where just three years ago we had found only one, and that one smaller than half the size of these enormous specimens. I would say this plant has found its happy home! An unusual feature of Green Dragon (a relative of the Jack-in-the-Pulpit) is that it has only a single leaf, but that leaf forks so that there appear to be two separate leaves, each containing 5 to 15 leaflets, curling around the stem in almost a complete circle. A separate flower stalk holds the long-tipped spadix, which protrudes beyond the narrow green spathe.
We sacrificed one spathe in order to have a good look at this fascinating flower, the staminate parts arrayed above the pistillate parts in order to spill their pollen below. Later in the summer, the now fertilized pistillate parts will yield a cluster of bright-red berries.
Of course, we found many other interesting plants at this rich site, including several that inhabited this steep shale bank very close to the river's edge.
We were amazed to find this single specimen of Kenilworth Ivy (Cymbalaria muralis) hiding out in a hollow of the shale bank. This pretty rock-garden plant is native to Mediterranean Europe, but it has become naturalized in many places here, having escaped from cultivation. It's a very pretty plant, with its dainty and colorful little flowers, but it can be invasive at times. But not at this site, so far.
As we rounded the trail where the Hoosic empties into the Hudson, a beautiful patch of White Beardtongue was also in glorious bloom right next to the water.
Apparently, as this wee little moth demonstrates, we weren't the only ones who found the peppermint-candy-striped flowers of Spreading Dogbane (Apocyum androsaemifolium) attractive.
I could have spent much more time at this rich site with my delightful companions, but I had to hurry away by noon in order to make my afternoon appointment in the woods at Skidmore College, where I would meet a group from Hobart and William Smith College and assist them in their search for area milkweeds.
Milkweed Hunting in Saratoga County
Somehow, the word had gotten out to Dr. Shannon Straub, Assistant Professor of Biology at Hobart and William Smith College in Geneva, N.Y., that I know where to find various species of milkweed in Saratoga County. Professor Straub's research involves trying to understand the evolution of North American milkweeds using DNA sequence data. Working with a collaborator in Oklahoma, she plans to collect individual plant-tissue samples from 20 populations of each milkweed species, in order to better understand the genetic diversity within the species and how they may have evolved. In her search for milkweed populations in eastern North America, she had found out that I could lead her to where several of the various milkweed species grow in my area. So on Thursday afternoon, I met with Professor Straub, as well as her four student interns (shown below, L-R) Meghan (in hat), Natalie, Sarah, and Liz.
Our search began in the woods at Skidmore College, where I had only recently located several sites where the woodland species of milkweed, Asclepias quadrifolia (Four-leaved Milkweed) was growing abundantly. Lucky for us, it was still in bloom, for this is a plant that is very difficult to discern on the forest floor after the flowers have faded.
While still at the Skidmore site, we visited some of the more interesting plants in this limestone-rich woods, including some that are found nowhere else in the county, such as Green Violet, Ginseng, and Goldenseal. The students took a lively interest in all that we found, including the tiny larva at the center of an Oak Apple Gall, which they are intently examining in the photo above.
After Professor Straub and her students obtained, labeled, and pressed specimens from the abundant populations of A. quadrifolia at Skidmore, we made our way north to Moreau Lake State Park. Here on a power line right-of-way above Mud Pond grow two more species of milkweed very close to each other, making collection quite efficient.
The first of these two species we found was this Asclepias amplexicaulis (Blunt-leaved Milkweed), not yet in bloom, but in nice fat bud. Our research group was able to locate eleven individuals at this site, allowing for the collection of a specimen without depleting the population. (It's important to note that Professor Straub had obtained all the necessary permissions and licenses allowing her to remove individual plants from otherwise protected sites. The general public would be forbidden to pick any plant on state park or Skidmore College property.)
The second species of milkweed found at this site was A. tuberosa, the bright-orange-flowered Butterflyweed. Again, this flower was not yet in bloom, but it did have well-developed buds and possessed abundant flowering stems, allowing for successful collection of a specimen. (Sorry, but I neglected to take a photo!) Here, Professor Straub (orange hat) demonstrates to her interns the correct way to label and prepare a specimen for pressing.
Their work with me completed -- they would later go on without me to collect specimens of Common Milkweed (A. syriaca) at the Saratoga Spa State Park -- we next took some time to explore and enjoy the Mud Pond site. Most of the students had never before experienced the delightful fragrance of Sweetfern (Comptonia peregrina), so I showed them how to pinch a few leaves to enjoy that wonderful scent.
We also walked down to the pond's muddy edge, where I pointed out the bright-yellow blooms of Common Bladderwort (Utricularia vulgaris ssp. macrorhiza), and lifted out of the water the plant's underwater structures, explaining how the tiny sacs sucked in tiny organisms, which the plant absorbs for its nutrients. And speaking of tiny organisms, I also pointed out all the itsy-bitsy little toadlets that were hopping all over the mud. One of the students managed to pluck one up from the mud for all of us to wonder at. How cute! (And I refrained from commenting on that little green nubbin stuck in the mud, one of my favorite liverworts called Ricciocarpus natans. I figured the students had probably heard enough of my instruction for one day!)