The Daily Bucket is a regular feature of the Backyard Science group. It is a place to note any observations you have made of the world around you. Rain, sun, wind...insects, birds, flowers...meteorites, rocks...seasonal changes...all are worthy additions to the bucket. Please let us know what is going on around you in a comment. Include, as close as is comfortable for you, where you are located. Each note is a record that we can refer to in the future as we try to understand the patterns that are quietly unwinding around us.
April 2014
San Juan islands, Pacific Northwest
Last week I bushwacked through the woods to collect a sample of wetland water. We saw a variety of early spring microscopic life, as well as larval newts, insects and cattails. Today I'd like to take you on a walk through the woods all the way around that marsh, to show you how dramatically communities differ in response to their microclimates. Small changes in environmental conditions make a big difference in what plants are successful, which then shapes the rest of the community.
Notably, nearly all the vegetation at this site is native. This coastal freshwater wetland and its surrounding woods has been used relatively lightly by people in comparison to the rest of the island, especially recently. It's a remote spot with difficult topography. Early on, Straits Salish Indians camped by the shore during the summers for fishing, clamming, hunting, and gathering plant foods such as cattails. During the later 19th century a settler fenced off the berm barrier between the beach and wetland for his house, barn and cow. A hundred years ago many trees were cut down when the whole county was logged for steamship fuel and the lime kilns. But this spot is a backwater on the island and uninhabited since farmer Merk left. It is now a Preserve. So variations in the plant communities are due mainly to the microclimate conditions: aspect, light, water, soil, and temperature.
We'll start our walk at the parking lot, and circle around the marsh within 20 feet of its edge. Ready for our half mile stroll?
(All photos by me. In Lightbox...click to enlarge)
From the upper end of the marsh, this wide path used to be a road to the beach, along the north-facing slope of the valley. Compared to the south-facing slope, this side gets less light, is cooler, and the soil stays moist. The land rises gradually here so runoff soaks in.
Evergreen Douglas Fir and Redcedar are common. Some young Grand Fir and Western Hemlock. Open sunlight near the marsh and the damp soil support Red Alder, Scouler's Willow and Pacific Crabapple.
Disturbed sites, like roads, promote opportunistic plants, aka "weeds". In this case, the weed is native Stinging Nettle (Urtica dioica).
Away from the path, there's much more understory diversity. In this one photo, an area the size of a pillowcase, I see Foamflower, Dewberry, Cleavers, Buttercup, Pathfinder, Fringecup and several mosses. None are flowering yet now, in mid April.
The trees are mixed age. On an alder snag a Hairy Woodpecker searches for spring insects. In another few weeks when these deciduous trees are leafed out, she'll be invisible.
At the beach we turn left, skirting the berm Merk cleared and farmed in the 19th century. On this dry sunny spot, Nootka Rose forms an impenetrable thicket. Rose spreads aggressively by rhizomes into cleared areas (which means elsewhere on the island, pastures and lawns must be regularly mowed!).
Most visitors stop here at the beach, but there is a narrow path through the thicket we can use to access the north side of the marsh. The edge of the path is grassy, one of the few non-native plants in the area, possibly planted for grazing Merk's cow.
Other shrubs that thrive in sunny dry conditions are Oregon Grape, now flowering, and Snowberry, yet to bloom. All three of these shrubs are food sources for animals, such as birds, chipmunks, butterflies. Thickets are great refuges too.
Turning inland, we have a sheer cliff on our right. While I was there that day I heard eagle and osprey. Peregrine falcons nest on the cliff. A Turkey Vulture soars overhead.
On this steep south-facing mass of bedrock, only a few plants find anchorage in cracks, and water runs right off into the marsh. The soil is fairly dry and vegetation gets lots of sun. At the base of the cliff the understory is mostly Salmonberry, Nootka Rose and Oregon Grape, with low Bracken Fern, grasses and succulents like Stonecrop.
Pacific Madrona grows beautifully here, and on the cliff face itself.
Douglas Maple has just leafed out with gusto. This species is well adapted to dryer soil, and in fact we have no naturally growing Vine Maple, common elsewhere in western Washington, which requires damper conditions (although I planted one in my backyard, just now starting to leaf out). Typical annual rainfall at this south end of the island is 18" a year.
An Orange-Crowned Warbler sang in a Douglas maple. Couldn't get a decent pic of it through the leafy branches. Along with this summer migrant I heard a Varied Thrush, a hummingbird, a kinglet and Spotted Towhees in the woods. And of course gazillions of RedWing Blackbirds out in the marsh.
The woods widen as we walk inland. Douglas Firs dominate now, with patches of Salal and the shade-loving Baldhip Rose. Mosses and Licorice Ferns carpet boulders fallen from the cliff. In the shady duff, native perennial orchids emerge from needles and cones and hardy moss. The patchy one is Rattlesnake Plantain, not yet in bloom, and the modest single leaf of a Calypso Fairyslipper. Nearby, other Fairyslippers have bloomed in sparkles of pink. Their presence is testament to the undisturbed nature of this area.
They require special conditions of shade, moisture and soil that cannot be duplicated outside of old-growth forest. The single leaf has a very limited ability to photosynthesize and so cannot provide all the nutrients the plant needs. This orchid, along with many others in the Pacific Northwest, grows in partnership with a fungus in the soil that shares nutrients taken from the roots of trees. So in a way, the orchid is using the needles of evergreen trees in the forest to provide the nourishment it needs through a fungus. For this reason, they won't grow if dug up and taken home.
The Calypso orchid is being rapidly exterminated in populated areas due to trampling and picking. The corms are attached by means of delicate roots. These roots can be broken by even the lightest tug of the stem. Hence, when the flower is picked the plant usually dies. Washington Native Orchid Society
At the upper end of the marsh the path is a tunnel through leafless curving Oceanspray branches and evergreen tree canopy.
I could smell them before I saw them. In the permanently wet upper end of the marsh margin, Skunk Cabbage is coming into bloom, surrounded by Slough Sedges and Ladyferns. The scent is pungent but not at all unpleasant.
We return to the parking lot through a slope damp with runoff trickling down to the marsh right now. Beside the path it's solid Sword Ferns and nurse logs under a Redcedar and Douglas Fir canopy. Sword Ferns are common where the soil is damp, acidic and rich in organic material.
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Our short walk around the marsh has taken us through several different woodland ecosystems, each with a distinct plant community well adapted to its particular set of conditions. There's a certain amount of overlap, and Douglas Fir does well most everywhere, but the differences speak to the importance of slight variations. As climate change takes hold here as everywhere, I wonder what these woodland communities will look like years hence, even within my own lifetime.
For the botanically inclined, here are lists of the plants mentioned in woodland communities we visited. By no mean comprehensive! Much vegetation has not greened up or flowered yet, for one thing.
However, every single plant named here is native to the island.
Community 1: Damp, moderate light, north facing aspect
Red Alder (Alnus rubra), Scouler’s willow (Salix scouleriana). Redcedar (Thuja plicata), Grand Fir (Abies grandis), Hemlock (Tsuga heterophylla), Pacific crabapple (Malus fusca), Douglas Fir (Pseudotsuga menziesii), Stinging Nettle (Urtica dioica), Foamflower (Tiarella trifoliata), Dewberry (Rubus ursinus), Cleavers (Galium aparine), Western Buttercup (Ranunculus occidentalis), Fringecup (Tellima grandiflora), Pathfinder (Adenocaulon bicolor), Mosses
Community 2: Dry, lots of light
Nootka rose (Rosa nutkana), Snowberry (Symphoricarpos albus), Oregon grape (Mahonia aquifolium)
Community 3: Moderately dry, moderate light, south-facing aspect
Madrona (Arbutus menziesii), Douglas Maple (Acer glabrum)
Douglas Fir, Salmonberry (Rubus spectabilis), Bracken fern (Pteridium aquilinum), Oregon grape , Stonecrop (Sedum spathulifolium), Salal (Gaultheria shallon ), Licorice fern (Polypodium glycyrrhiza), Baldhip rose (Rosa gymnocarpa), Oceanspray (Holodiscus discolor), Rattlesnake Plantain (Goodyera pubescens), Fairyslipper (Calypso bulbosa)
Community 4: Wet runoff channel, moderately light
Redcedar, Douglas Fir, Sword fern (Polystichum munitum), Ladyfern (Athyrium filix-femina), Skunk cabbage (Lysichiton americanus), Slough sedge (Carex obnupta), Water parsley (Oenanthe sarmentosa), Cleavers, Dewberry
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Now it's your turn. Nature news or changes in your backyard? All observations are welcome in the Bucket.
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