Field Guides and Floras: • Magee, Dennis W
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* THE SHORT ALDRICH TRAIL SPRING EPHEMERAL PLANTS Isabel Marlens Spring 2012 * 1 Introduction . .3 The Short Aldrich Trail . .4 Plant Profiles:* Claytonia caroliniana . 6 Sanguinaria canadensis . 7 Anemone acutiloba . 8 Caulophyllum thalictroides . 9 Dicentra cucullaria . 10 Cardamine spp . .11 Erythronium americanum . .12 Ranunculus abortivus . .13 Trillium erectum . 14 Viola spp. .. .15 Dicentra canadensis . .17 Trillium grandiflorum . 18 Tiarella cordifolia . 19 Arisaema triphyllum . .20 Mitella diphylla . .21 Asarum canadense . 22 Polygonatum biflorum . .23 End Note . .24 Sources . .24 *Because this field guide has a focus on first flowering dates, the plant profile order is based upon phenological characteristics. 2 INTRODUCTION Nature's first green is gold, Her hardest hue to hold. Her early leaf's a flower; But only so an hour. Then leaf subsides to leaf. So Eden sank to grief, So dawn goes down to day. Nothing gold can stay. – Robert Frost Robert Frost wrote this small poem about, among other things, death and spring ephemeral plants three years after he moved to a farmhouse in Shaftesbury, Vermont. The house is scarcely five miles, as the crow flies, from the Short Aldrich Trail in North Bennington. The poem is one of the most famous in a collection that won the Pulitzer Prize. It is not hard to see why. It reflects a fixation – a common one, perhaps, because it is so caught up with our perceptions of beauty, of grief, of human life and loss – with the pathos of precious things that seem to fade too fast. Spring ephemerals represent perfectly the notion of the exquisite that cannot last. Spring ephemerals flower early in spring, before summer's foliage shades the forest floor. Their colors are often more tender, their petals more delicate than those of the flowers that must weather the summer. Their pollinators are primarily queen bees – of the genus Bombus – that have passed the winter beneath the leaf litter. Ants disperse most spring ephemeral seeds, and so these seeds rarely travel far or quickly. Moreover, all the species (but one) in this field guide are relatively long-lived perennials, needing time to grow and establish. Many of these species are only found in primary-growth woodlands, and in those woodlands that have grown a relatively long time since a clearing. This makes them good indicators of land-use history, and of a forest stand's current state of succession and levels of native biodiversity. It has recently been suggested that spring ephemerals may, in other ways, serve as indicator species. Scientists have found that many species of flower are blooming earlier now than they did in the past, seemingly a result of global climate change. Abraham Miller-Rushing and Richard Primack, using a data set begun by Henry David Thoreau in the 1850's, found that early-blooming species in particular are subject to climate-driven shifts in phenology, which are associated with rises in mean winter and spring temperatures. The consequences of such shifts are not yet well understood, but we have reason to fear that, by creating plant-pollinator 3 mismatches, they might lead to the decline of certain woodland species, to the increase of others – to changes, in short, in spring woodland flower communities that could end in extinction and a loss of biodiversity. They may end, if nothing else, in the loss of lovely things. For this reason, observations on flowering spring ephemeral plants have become increasingly valuable. At the least, we can document loss and change; though we may hope to build a foundation for gaining further knowledge that would inform human behavior and management techniques. In summer, the spring ephemerals will fade, as they have always done. Yet it would make one just a little hopeless to think they might not return the next spring. * * * THE SHORT ALDRICH TRAIL For the purposes of this field guide, the Short Aldrich Trail is divided into five sections – beginning with the map of the Park-McCullough trails at the trailhead off West St.. These sections will be referred to throughout the plant profiles, so that one reading this guide might, in future years, locate the species described. Section I: This is the Mile-Around-Woods trail itself, and the narrow footpath that links the loop with the field to the south. As, in walking the Short Aldrich Trail, one can take either the east or the west fork, this section includes both. The whole area is reasonably homogeneous. It is mostly level, so aspect does not create significant variation. The canopy is in a fairly late stage of succession, and is dominated by beautiful Fagus grandifolia (American beech) and Acer saccharum (sugar maple). Late in the spring, a carpet of Galium aparine emerges, and some invasives, including Lonicera morrowii (bush honeysuckle), Berberis thunbergii (Japanese barberry), and Alliaria petiolata (garlic mustard) can be found along the wood edges. Nevertheless, the understory here is home to a diverse community of native spring ephemeral plants. The large clusters of Dicentra canadensis, and the vast patches of Trillium grandiflorum are particularly pleasing. Section II: One reaches this section after crossing the open field to the south of the Mile- Around-Woods and turning left at the sign for the Short Aldrich Trail. Upon ducking under a hedge of honeysuckle, one begins to climb a west-facing slope. Two thirds of the way up lies a beautiful moss-covered stone wall; there is another stone wall on the east-facing side of the hill. Along the hill's crest – between the two walls – certain species, like Caulophyllum thalictroides (blue cohosh), are notably more plentiful than they are outside the walled-in area. This may be because the terrain here is quite steep, and a small patch of the canopy is still, remarkably, primary growth. This area is dominated by large Acer saccharum (sugar maples). The understory is open and airy, not overgrown either with invasives or with large native species – though late in the season it becomes a rolling green sea of jewelweed. Nevertheless, many of the most lovely and delicate early-spring ephemerals can be found here (either first or exclusively) particularly in the sunshine of the southeast-facing slope. These include: Sanguinaria canadensis, Claytonia 4 caroliniana, Erythronium americanum, the exquisite Anemone acutiloba, and many species in the genus Viola. Exiting Section II, one must walk on the road for a time before crossing 67A and Paran Creek and descending again onto the Short Aldrich Trail. Section III: This section of the trail skirts an old millpond and some marshy areas. It is relatively wet and shaded – the canopy being dominated by evergreens – primarily young Pinus strobus (white pine). In addition, one finds large shrubs (mostly honeysuckle), though native shrubs, like wild raspberries (Rubus spp.), grow here as well. Except for these shrubs, and a number of weedy grasses and dandelions, the understory is a carpet of coppery needles. A few extraordinarily large and majestic white pines are the area's main appeal. Section IV: This segment of the trail ascends the hill towards the main part of the Bennington College campus. It is the most vegetatively diverse segment of the eastern Short Aldrich Trail. The canopy is early-successional, and includes Carya cordiformis, (bitternut hickory), possessor of the most beautiful, yellow-velvet leaf buds in the forest; these can be found above the spring ephemerals, before the canopy leaves unfurl. Beside the bitternut hickory grows Carpinus caroliniana (muscle-wood or blue beech), with its graceful limbs. A number of small Quercus spp. (oaks), Ostrya virginiana (hop hornbeam), Acer saccharinum (silver maple), Acer rubrum (red maple), and even some small Acer saccharum (sugar maples) can be found here as well. Though this area did experience disturbance more recently than its western Short Aldrich counterparts, one does find certain spring ephemerals – most notably, a great many Erythronium americanum and Arisaema triphyllum. Many ferns also grow here: Christmas ferns (Polystichum acrostichoides), with their rounded, once-cut fronds; and evergreen wood ferns (Dryopteris intermedia), lacy, ethereal, thrice- cut, yet tough enough to last the winter through. In an open clearing just at the top of the hill one finds a large group of Matteuccia struthiopteris, the crowned and colony-forming ostrich fern, with its tall (100-170 cm), tapering plumes. Section V: This final section begins in a Pinus strobus plantation, and here the understory vegetation is scarce – though some garlic mustard, certain wood ferns, and even a few Arisaema triphyllum can be found. Once one emerges from the P. strobus plantation the early-successional canopy and the thick cover of honeysuckle describes a highly and recently disturbed woodland. The canopy species include Populus tremuloides (trembling aspen) and Acer rubrum (red maple). A great golden Betula alleghaniensis (yellow birch) marks the trail's end, its roots, like metallic snakes, coiling across the path. Though the understory is dominated by garlic mustard, honeysuckle, and ferns, early in the season one does find a few spring beauty plants. 5 * Claytonia caroliniana Michaux, 1803 Montiaceae Carolina Spring Beauty Note on Taxonomy: Claytonia is named for John Clayton (1694-1773), a Colonial plant collector in Virginia. According to many sources, including Flora of North America and Flora Novae Angliae, the genus Claytonia belongs to the family Portulacaceae (Purslane family). But currently taxonomists place it in the family Montiaceae. Claytonia caroliniana is often the first ephemeral one sees in spring; it is also one of the longest lasting. Spring beauty blooms from March to June. In 2012, it was found in Section II on 22 March, and in Section I on 2 April. It could soon be seen along the length of the trail – though it remained far more rare on the east side.