Kill the Thistles... Right?

In early July I made a trip to a northwest Indiana location to see a thistle.  "Why would anyone travel to see a thistle," you ask?  Thistles are common weeds in almost every old field, right?

 

Not this one.  To the untrained eye, the plant in these photographs may look a bit like Bull Thistle (Cirsium vulgare), but you can see at the bottom of the above photograph that the stem below the flowering head is not winged and spiny, as it would be in Bull Thistle.  In addition, this thistle would be dwarfed by Bull Thistle, as it grows to just over half a meter tall at the most.  No, I didn't make the hour-plus drive to see a weed; I was visiting a known site for one of the rarest thistles in North America, a Great Lakes endemic, Hill's Thistle (Cirsium hillii).  I had planned my trip for early July because Hill's Thistle should have been in peak bloom, but as a result of the weird weather year that was 2012, all but one of the plants in the small population had finished blooming, and the one that still was flowering was well past its peak.  Hill's thistle was first collected back in 1890 by Rev. E.J. Hill, not more than a few miles from the location where I saw it in 122 years later.

Hill's Thistle is only known from six states and one Canadian province surrounding the Great Lakes; it is listed as endangered or threatened in three of them and special concern in others, but more importantly, it is considered globally vulnerable.  Not only is it already rare, but populations of Hill's Thistle are declining as a result of habitat loss, in part due to fire suppression and the litter accumulation and succession from prairie to shrubby habitat that comes as a result.  In addition, Hill's thistle is a short-live perennial species, with a life span of two to five years, and it only produces flowers in the final one to three of those years; if the seed isn't successful in germinating in those years, the plant simply doesn't reproduce.  Aside from locations close to the lakes, Hill's Thistle is focused in counties along the Mississippi River.  This rare thistle has been found in habitats including prairies, savannas, barrens, and open woodlands, as well as in limestone pavement alvars.  Hill's Thistle is sometimes treated as as variety of Pasture Thistle (Cirsium pumilum), a plant of the eastern (mostly northeastern) United States.

Adirondack Foray, Part II

I previously posted Part I of my Adirondack Foray with Bruce Behan.  When I left off, we had completed the first half of our second (of three) days of botanizing.  After leaving Spring Pond Bog, we traveled to the 900-acre Clintonville Pine Barrens, where we only had a few hours of remaining daylight to explore this unique Pitch Pine-Heath Barren community. 

 

Clintonville Pine Barrens

At this Nature Conservancy preserve, an open canopy dominated by Pitch Pine (Pinus rigida) has developed on top of the sandy soil deposited approximately 12,000 years ago by melting glaciers. Common acidophile shrubby understory plants that we observed that help to give the Pitch Pine-Heath Barren community its name include Kinnikinnick (Arctostaphylos uva-ursi), Sweet Fern (Comptonia peregrina), Northern Bush Honeysuckle (Diervilla lonicera), Eastern Teaberry (Gaultheria procumbens), Black Huckleberry (Gaylussacia baccata), Sheep Laurel (Kalmia angustifolia), two varieties of Lowbush Blueberry (Vaccinium angustifolium var. angustifolium and V. angustifolium var. nigrum), and Blue Ridge Blueberry (Vaccinium pallidum). Some of the other characteristic plants that we saw include Striped Maple (Acer pensylvanicum), Red Maple (Acer rubrum), Spreading Dogbane (Apocynum androsaemifolium), Red Columbine (Aquilegia canadensis), Wild Sarsaparilla (Aralia nudicaulis), Flaxleaf Whitetop Aster (Aster linariifolius), Bigleaf Aster (Aster macrophyllus), Wavyleaf Aster (Aster undulatus), Pennsylvania Sedge (Carex pensylvanica), Pipsissewa (Chimaphila umbellata), Bastard Toadflax (Comandra umbellata), Beaked Hazelnut (Corylus cornuta), Wavy Hairgrass (Deschampsia flexuosa), American Beech (Fagus grandifolia), Tree Groundpine (Lycopodium dendroideum), Whorled Yellow Loosestrife (Lysimachia quadrifolia), Canada Mayflower (Maianthemum canadense var. canadense), Purple Chokeberry (Photinia floribunda), Red Pine (Pinus resinosa), Eastern White Pine (Pinus strobus), Sandcherry (Prunus pumila), Chokecherry (Prunus virginiana), Western Brackenfern (Pteridium aquilinum), American Wintergreen (Pyrola rotundifolia var. americana), White Oak (Quercus alba), False Melic (Schizachne purpurascens), Strict Blue-eyed Grass (Sisyrinchium montanum), Broad-leaved Meadowsweet (Spiraea latifolia), Starflower (Trientalis borealis ssp. borealis), and Velvetleaf Huckleberry (Vaccinium myrtilloides).  Birds of interest included Eastern Wood-Pewee (Contopus virens), Nashville Warbler (Oreothlypis ruficapilla), Ovenbird (Seiurus aurocapilla), Blackburnian Warbler (Setophaga fusca), Pine Warbler (Setophaga pinus), and Red-breasted Nuthatch (Sitta canadensis).


Ceanothus herbaceus

One of our target plants at Clintonville Pine Barrens was the rare Prairie Redroot (Ceanothus herbaceus), a plant listed as endangered in New York.  We weren't on the site more than 10 minutes before we found this low shrub in full flower.  Also known as Jersey Tea, this species is very similar to New Jersey Tea (Ceanothus americanus), but differs in that the inflorescences are found at the end of the current year's growth (in New Jersey Tea, the inflorescences are borne on long stalks from the upper leaf axils).  Prairie Redroot is known primarily from the central United States, from Texas through Minnesota and Wisconsin, and into Canada, reaching back south into upstate New York.  It can be found in prairies, fields, and other open areas in dry and often rocky or sandy soil.

Cypripedium acaule

Moccasin Flower (Cypripedium acaule) is, dare I say, fairly common in the northeast.  In fact, we saw this attractive orchid at all but one of the sites we visited during our trip.  We saw this species in dry acidic soils in forests and shrubby barrens, but it also grows in saturated acidic conditions, such as in bogs and swamps.  In addition to the New England states, Pink Lady's Slipper, as it is also known, grows south along the Appalachian Mountains, and also in the Great Lakes states; it also reaches north into much of Canada.  While at Clintonville Pine Barrens, Bruce kept talking about the elusive white Moccasin Flower, and it wasn't until I got home and was looking at my photographs that I realized that I'd actually seen the white Moccasin Flower, Cypripedium acaule forma albiflora.  In addition to the white or very faintly pink-tinged floral lip, the white form of Moccasin Flower lacks pigmentation in the petals and sepals, leaving them yellowish green instead of brownish or purplish as in the typical and much more common form.

Cypripedium acaule f. albiflora

We began our final day of botanizing in the Adirondacks with a trip to The Nature Conservancy's Gadway Sandstone Pavement Barrens Preserve in Clinton County, New York.  This 520-acre preserve harbors several interesting plant communities, including Sandstone Pavement, Mixed Mesic Upland Forest, Swamp, and Jack Pine-Heath Barrens. 

Gadway Sandstone Pavement Barrens Preserve

Many different types of natural processes have combined to form our natural communities.  The Sandstone Pavement community is thought to have formed when a catastrophic flood from the abrupt drainage of Glacial Lake Iroquois stripped the topsoil and glacial deposits from the land, leaving bare sandstone.  In the 11,000 to 12,000 years since that time, a very thin layer of nutrient poor soil has formed in spots.  Early colonizers such as mosses and lichens are abundant, and shallow-rooted vascular plants that can tolerate low pH levels have taken advantage of the harsh site conditions.  The result is a globally rare plant community known from fewer than 20 sites on Earth.  Many of the plants, especially in lower areas, can tolerate at least seasonal inundation, giving rise to interesting wetlands in very shallow soils over sandstone bedrock.

Wet spot on the sandstone pavement

Where slightly deeper soils are present, Jack Pine-Heath Barrens have formed.  These fire-dependent communities are similar to the Pitch Pine-Heath Barrens observed at Clintonville Pine Barrens in that they are dominated by acidophiles that can survive in low nutrient soils.

Jack Pine-Heath Barrens community at Gadway Sandstone Pavement Barrens Preserve

Plant species that we observed in the Sandstone Pavement that are characteristic of this community include Red Maple, Paper Birch (Betula papyrifera), Wavy Hairgrass, Eastern Teaberry, Black Huckleberry, Narrowleaf Cowwheat (Melampyrum lineare), Purple Chokeberry, Jack Pine (Pinus banksiana), Red Pine, Eastern White Pine, Western Brackenfern, Northern Red Oak (Quercus rubra), and Lowbush Blueberry.  Other plants of interest observed at the preserve include Striped Maple, Gray Birch (Betula populifolia), Northern Shorthusk (Brachyelytrum aristosum), Drooping Woodland Sedge (Carex arctata), Silvery Sedge (Carex canescens), Fibrousroot Sedge (Carex communis var. communis), Nodding Sedge (Carex gynandra), Bluebead (Clintonia borealis), Threeleaf Goldthread (Coptis trifolia), Bunchberry Dogwood (Cornus canadensis), Moccasin Flower, Northern Bush Honeysuckle, Intermediate Woodfern (Dryopteris intermedia), Marginal Woodfern (Dryopteris marginalis), Trailing Arbutus (Epigaea repens), Catberry (Ilex mucronata), Butternut (Juglans cinerea), Common Juniper (Juniperus communis), Canada Mayflower, Indian Cucumber (Medeola virginiana), Roughleaf Ricegrass (Oryzopsis asperifolia), Rock Polypody (Polypodium virginianum), Arctic Rattlebox (Rhinanthus minor ssp. groenlandicus), Broad-leaved Meadowsweet, New York Fern (Thelypteris noveboracensis), Starflower, Painted Trillium (Trillium undulatum), Velvetleaf Huckleberry, and Withe-rod (Viburnum nudum var. cassinoides).

Kalmia angustifolia

Although we saw Sheep Laurel at many of the sites we visited, including Gadway Sandstone Pavement Barrens Preserve, it is considered exploitably vulnerable in New York.  This is a testament to the beauty of this Ericaceous shrub, as it is often collected for garden and ornamental use.  That said, Sheep Laurel is listed on the Canadian weed list because of its ability to invade commercial shrub and tree plantations, and it is likely physically removed from similar situations in the United States.  In addition, because its foliage contains the glycoside andromedotoxin, which is deadly to animals (leading to another common name of Sheepkill), Sheep Laurel is likely often removed from pastures.  Found primarily in New England, the northern half of the lower peninsula of Michigan, and Canada, Sheep Laurel occurs in bogs, swamps, and other wet areas with low pH, often in sandy soil.

The final botanical destination on our foray left us just steps away from the US-Canadian border, as we visited The Gulf Unique Area in Clinton County.  At this interesting New York State Department of Conservation site we wandered through Swamp Forest, Mixed Mesic Upland Forest, Sedge Meadow, and Dry Upland Coniferous Forest.

Swamp at Gulf Unique Area

Because of the range of plant communities at The Gulf Unique Area, we encountered a wide variety of plants.  Some of the highlights and characteristic species we saw in the Swamp Forest include Paper Birch, Brownish Sedge (Carex brunnescens), Silvery Sedge, White Edge Sedge (Carex debilis var. rudgei), Threeseeded Sedge (Carex trisperma), Threeleaf Goldthread, Woodland Horsetail (Equisetum sylvaticum), Eastern Teaberry, Threeleaf False Lily of the Valley (Maianthemum trifoliatum), Indian Cucumber, Buckbean (Menyanthes trifoliata), Cinnamon Fern (Osmunda cinnamomea), Steeplebush (Spiraea tomentosa), Eastern Hemlock (Tsuga canadensis), and Withe-rod.  In the Mixed Mesic Upland Forest we enjoyed seeing Balsam Fir (Abies balsamea), Striped Maple, Yellow Birch (Betula alleghaniensis), Drooping Woodland Sedge, Fibrousroot Sedge, Bluebead, Bunchberry Dogwood, Moccasin Flower, Northern Bush Honeysuckle, Intermediate Woodfern, Black Huckleberry, Shining Clubmoss (Huperzia lucidula), Twinflower (Linnaea borealis), American Fly Honeysuckle (Lonicera canadensis), Stiff Clubmoss (Lycopodium annotinum), Tree Groundpine, Canada Mayflower, Eastern White Pine, Rock Polypody, Western Brackenfern, Skunk Currant (Ribes glandulosum), Red Elderberry (Sambucus racemosa var. racemosa), Twistedstalk (Streptopus lanceolatus var. lanceolatus), Heartleaf Foamflower (Tiarella cordifolia), Starflower, Red Trillium (Trillium erectum), Painted Trillium, Lowbush Blueberry, Velvetleaf Huckleberry, Hobblebush (Viburnum lantanoides), and Sweet Wild Violet (Viola blanda var. palustriformis).  The Sedge Meadow was characterized by Purplestem Aster (Aster puniceus), Bottlebrush Sedge (Carex hystericina), Lake Sedge (Carex lacustris), Upright Sedge (Carex stricta), Bulblet-bearing Water Hemlock (Cicuta bulbifera), American Mannagrass (Glyceria grandis), Earth Loosestrife (Lysimachia terrestris), Tufted Loosestrife (Lysimachia thyrsiflora), Great Water Dock (Rumex orbiculatus), Broad-leaved Meadowsweet, and Eastern Marsh Fern (Thelypteris palustris var. pubescens).  Balsam Fir, White Spruce (Picea glauca), and Eastern White Pine were characteristic of the Dry Upland Coniferous Forest.  As we were leaving The Gulf Unique Area, we stopped the car to see Black Ash (Fraxinus nigra), Ostrich Fern (Matteuccia struthiopteris), and Perfoliate Bellwort (Uvularia perfoliata) in a Deciduous Mesic Upland Forest, and in the process we flushed an Ovenbird.  I continued to watch this ground-dwelling warbler until I found her characteristic oven-shaped nest.

Calla palustris

In the Swamp Forest at The Gulf Unique Area we came across a sphagnum slough full of Water Arum (Calla palustris).  If you're a regular reader of this blog, you've seen photographs of, and read commentary on, Jack-in-the-Pulpit (Arisaema triphyllum) and Skunk Cabbage (Symplocarpus foetidus).  Like these two species, Water Arum is in the family Araceae, and all three species share the common trait of having a conspicous sphathe surrounding a spadix covered with tiny, incospicuous flowers.  When it goes to fruit, the spadix will be covered with bright red, fleshy berries.  As with many things in nature, the bright red fruits of Water Arum indicate that they are poisonous; in fact, the entire plant is extremely poisonous, and if you eat it you will experience painful swelling (or so I'm told).  Water Arum grows in bogs, swamps, and marshes, as well as along rivers, ponds and lakes.  Its geographical range in the United States includes the New England states and the upper Great Lakes region; it is also found throughout Canada.

Oxalis montana

I was thrilled to locate a population of Mountain Woodsorrel (Oxalis montana) within the Mixed Mesic Upland Forest at The Gulf Unique Area.  Unlike the previous species, you can eat Mountain Woodsorrel without hesitation, and the sour leaves make a nice addition to a salad.  This low-growing climax forest species is known from the New England states and south along the Appalachian Mountains, as well as from the upper Great Lakes region and eastern Canada.  It grows in moist forests, often in mosses under conifers. 

Driving back to our cabin to spend our last night in the Adirondacks, Bruce and I made one last stop to see the "Grand Canyon of the East," Ausable Chasm, in Clinton and Essex counties.  This magnificent sandstone gorge has formed as a result of more than 500 million years of glacial movements followed by the Ausable River carving out a channel as it leads into Lake Champlain.  The result is a 2 mile long, 150 foot deep New York State Department of Environmental Conservation Unique Geologic Feature.

Ausable Chasm

Thanks Bruce, for a fantastic spring botanical outing and for showing me some spectacular natural areas!  As you can tell, I had an amazing time.

Bruce Behan