Monday, October 13, 2008

Rare Plant Communities of Metchosin

March 20, 2005

The combination of the climate in our area and the varied geography of Metchosin unite to produce a series of linked landscapes within our community. From the sand and cobble beaches along Metchosin and William Head Roads to pastoral farmlands, from Garry oak meadows to upland mountain tops, we are unique on the lower island in the diversity, complexity and relatively pristine condition of our ecosystems.
Some of these are considered rare plant communities. Plant communities are a certain mix of plants that occur together because of growing conditions that include soil type and fertility, moisture, slope and light. One of the most common rare plant communities is the Garry oak ecosystem over which many words have been spent, but did you know we have other, equally uncommon and remarkable plant communities?
On gentle slopes and along ridgetops on shallow, fast draining soils over bedrock you will find the rare plant community known as Arbutus-hairy manzanita. These slopes generally face from southeast to southwest, have an exceptionally pronounced dryness and very poor to medium soil richness. Shore pines with deep ridged bark stand alone or in small groups. Rolling rocky knolls are thickly covered with a variety of mosses and lichens, and bonsai-like manzanitas with their blue-green evergreen leaves and crimson bark appear as if they were lifted from an ancient Japanese garden. Scattered on the ground you will find blue wildrye and Roemer’s fescue, interspersed with rattlesnake plantain, yarrow and wild strawberry. A few white fawn lilies, tigerlilies and death camas round out a scene of exquisite beauty.
Another rare plant community is the Douglas-fir-arbutus community. It occurs on similar dry southerly exposures or on flat well drained gravelly soils, with very poor to medium fertility. The large old growth Douglas-fir are rare as hens teeth but some younger trees are becoming mature and with arbutus comprise most of the tree layer with the occasional Garry oak, cascara, shore pine, western flowering dogwood, western yew or western redcedar. Oceanspray can be common along with snowberry, Oregon grape, baldhip rose, saskatoon, salal and huckleberry vines. The incomparable Calypso bulbosa or fairy slipper orchids as well as the wonderful variagation in the leaf of the rattlesnake plantain are jewels in the groundcover. Two of our rarest plant species, white top aster and Howell’s triteleia can also be found here.
A third rare plant community is the rock outcrop or mossy bald which often occurs as small openings in forested areas. With gentle to moderate slopes and thin soils this plant community is generally devoid of trees and shrubs but is home to kinnikinnick, junegrass, yarrow, harvest lily, Hooker’s onion and hoary rock moss. In the seepage areas and vernal pools that remain wet all winter and spring but dry out in the summer you will sometimes find the rare winged water-starwort and creeping spearwort or the delicate and lovely slim-leaf onion. The moss layer here is very fragile and the plants are easily dislodged by even a hikers boot. ATV’s, horses and mountain bikes can devestate in minutes what it took the landscape centuries to evolve. These sites often offer spectacular views as well as exceptional wildflower displays and they are rapidly being lost to development as house sites.
These remnant pieces of the coastal Douglas-fir mosaic are woth our attention and preservation. When they are gone, they will never return, so perhaps it behoves us to consider what avenues we may explore to ensure their continued existence within Metchosin.

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