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Park Ecosystems (Communities)The following section on ecosystems, Wild Plant Communities of Beacon Hill Park, was written by Dr. T. Christopher Brayshaw, August 28th, 1998. Seven 'native' vegetation types are represented in the southern part of Beacon Hill Park. However, as a consequence of a century or more of increasingly intense disturbances, all of them now bear plant communities composed of mixtures of native and exotic species. These vegetation communities are as follows:
Camas (Camassia quamash), Easter Lily (Erythronium oreganum), Death camas (Zygadenus venenosus), Western Buttercup (Ranunculus occidentalis), and many other flowering species still contribute to an abundant Spring flower show in the strange company of European grasses dominated by Perennial Ryegrass (Lolium perenne), Sweet Vernal Grass (Anthoxanthum odoratum), Orchard Grass (Dactylis glomerata), Velvet Grass (Holcus lanatus), and annual species of Bromus &c. (Brayshaw, 1993). Some formerly reported rarities have now disappeared. The Golden Paintbrush (Castilleja levisecta) and Prairie Lupin (Lupinus lepidus) have not been seen since 1995. The Camas (Camassia quamash and c. leichtlinii), noted for its masses of blue flowers in the Spring, can be taken as a visible monitor of the health of the wild plant community as a whole. Once forming solid blue carpets, this species now seems to be in gradual decline as a result of human impact. At one time, the mowing of the grass in Spring, as a fire-deterrent measure, would cut off the flowering stems before they could produce mature seeds. However, in recent years, communication between the Friends of Beacon Hill Park and the Parks Department has led to later mowing on the most sensitive slopes until the spring-flowering plants have shed their seeds. Still, the trampling of increasing numbers of people, especially in conjunction with scheduled events on or adjacent to the wild areas of the park has been a persisting source of concern regarding the well-being of the flowering species (see Part B). As the native plant species decline, they are replaced by increasing populations of exotic weedy plants that are able to withstand mowing and trampling, such as Ribgrass (Plantago lanceolata), Fall Dandelion (Hypochaeris radicata), and Daisy (Bellis perennis). Other activities that tend to reduce the integrity of the grassland community and to be detrimental to the future welfare of its flowering plants include the increasing intensity of trampling during scheduled events, and the planting up of the open areas, especially of Beacon Hill itself, with exotic trees, such as Pines and English Elm, shrubs such as Broom (Cytisus), and herbaceous plants such as Daffodils (Narcissus pseudonarcissus) and Bluebells (Endymion non-scriptus). Camas will die out under a canopy of Pines, and will disappear from the affected areas. The Elm is liable to sucker from its roots, and generate dense thickets in which nothing else can grow (Brayshaw, Oct. 1991).
In the park it is found on the upper northern slopes of Beacon Hill and in an area at the north end of the park. The stands in this park are relics of the only extensive original Canadian Garry Oak stand; which is now occupied by the built-up area of Greater Victoria. Most remaining stands are small, and are situated on private land, and threatened with destruction as clearing and subdivision proceed (Brayshaw, 1996). There are two forms of this woodland in the park, which are distinguished by their ground-cover types: - (a) the grassy form, and (b) the shrubby form. The factors determining which of these forms is found at any point probably include soil depth and the frequency of past fires. (a) The grassy Oak WoodlandThe grassy Oak woodland resembles an extension of the open grassland among the Oak trees. However, the grassy component, which includes native and exotic grasses, appears rather more luxurient here than in the open, treeless grassland. This community features a rich flora of Spring-flowering plants. Bulbous-rooted plants, such as the Tall Camas (Camassia leichtlinii), Easter Lily (Erythronium oreganum), Hyacinth Brodiaea (Triteleia hyacinthine), and formerly, Menzies' Larkspur (Delphinium menziesii) reach their greatest abundance in this community. The rare Balsam-root Sunflower (Balsamorhiza deltoidea) is reduced to one large plant on Beacon Hill, and the Fern-leafed Lomatium (Lomatium dissectum) is known by two plants nearby. Menzies' Larkspur (Delphinium dissectum), formerly recorded from this community, has not been seen here since about 1995. The richness and integrity of this community are strongly threatened by attempts to "improve" nature, by interplanting the native Oaks with exotic pines and English Elm (Ulmus procera) on Beacon Hill, and introducing Daffodils (Narcissus pseudonarcissus), and English Bluebell (Endymion non-scriptus). As they grow up, pines and elms will overtop the oaks, since they do not shape themselves to the wind as do the oaks. The pines, by their needle deposits, will render the ground beneath them unreceptive to the establishment of native flowering herbaceous plants: while the elms are more likely to become the centres of spreading dense thickets of suckers, with which the herbaceous flowers cannot compete. This community is most susceptible to invasion by Broom (Cytisus scoparius). (b) The shrubby Oak WoodlandThe shrubby Oak Woodland features an understory dominated by Snowberry (Symphoricarpos albus) accompanied by Nootka Rose (Rosa nutkana), and, in places, by Indian Plum (Osmaronia cerasiformis). Trailing Blackberry (Rubus ursinsu) and Himalayan Blackberry (Rubus discolor) are found here; and Ivy (Hedera helix) is a conspicuous invader, and, on Beacon Hill, a still unidentified exotic species of Prumus is spreading.
Associated trees include Broadleaf Maple (Acer macrophyllum), Red Alder (Alnus rubra), and Yew (Taxus brevifolia). The young Western Hemlock trees (Tsuga heterphylla) are believed to have been planted, since no adult trees or old stumps of that species are seen here. The precise composition of the original community is hard now to reconstruct, since, over the years, the wood has suffered alternate episodes of clearing and planting in the understorey, where a number of exotic trees and shrubs have been introduced. In the past, Salmonberry (Rubus spectabilis), Ocean Spray (Holodiscus discolor), Mock-orange (Philadelphus lewisii) and Indian Plum have all been important native shrubs. Much of the grassy woodland floor is modern, stemming from the most recent episode of undergrowth clearance. Persistent native herbs include Sword Fern (Polystichum munitum), Wild Lily-of-the-valley (Maianthemum dilatatum), and Stinging Nettle (Urtica dioica). The grasses are largely introduced species, but Sitka Brome is a persisting native grass. Many native undergrowth species have been re-introduced in recent years through the efforts of the Friends of Beacon Hill Park.
Accompanying trees include Trembling Aspen (Populus tremuloides), Wild Crabapple (Malus diversifolia), and, surprisingly, a few Garry Oak. A few young Western Red-cedar (Thuja plicata) are seen, but no old trees or old stumps. The understorey is dominated by Red Osier Dogwood (Cornus stolonifera), which is accompanied by Scouler's Willow (Slix scouleriana) and Salmonberry.
The community is transitional in aspect between the above two woodland types, but lacks conifers except for scattered Grand Fir, Douglas-fir and young Western Red-cedar in the belt adjacent to the Douglas-fir woods. Elsewhere, occasional Black Cottonwoods stand above a low-canopy wood made up mainly of Aspen, Scouler's Willow and Bitter Cherry (Prunus emarginata). Small Garry oaks also occur. This community is invaded by English Elm, English Hawthorn (Crataegus monogyna), Holly (Ilex aquifolium) and Ivy. Important understorey shrubs include Red Osier Dogwood, Nootka Rose, Salmonberry, Hardhack (Spiraea douglasii) and Morck-orange; and Snowberry occupies a bordering fringe. Characteristic herbaceous ground cover plants include Evergreen Sedge (Carex obnupta) and Cleavers (Galium aparine).
Added to the natural erosion is the human erosion associated with trampling, and the making of trails down to the beach. The impact of salt spray is an environmental factor that must be tolerated especially inWinter storms. No doubt because of this instability, the flora of this formation includes a larger proportion of exotic species than does that of the other communities. Much of this community now is made up of a mixture of native and exotic species in almost equal proportions; with native-dominated and exotic-dominated sub-communities forming a mosaic. Generally, the community is shrubby in structure, with Snowberry and Nootka Rose dominating much of it; but Bitter Cherry dominates an area just east of Finlayson Point. A notable change in recent years has been the invasion and rapid spread of English Elm in the area between in the area between the south end of Douglas Street and Finlayson Point during the past twenty-five years. Scattered seedlings have appeared, and have become the centers of spreading dense thickets of suckers, in which almost nothing else can grow. At its present rate of spreading, this elm could become the dominant tree of a wood in that area within the next twenty years.
The Rabbitfoot Beardgrass (Polypogon monspeliensis) is an invader from Europe. Gumweed (Grindelia integrifolia) is a conspicuous native perennial that occurs in both this and the preceding community. Its little flowering parasite, the California Broomrape (Orobanche californica), formerly more common, is not now known on the Beacon Hill foreshore. This zone is heavily used by people walking along the seashore, and, being very narrow, is suffering accordingly.
Excerpted
from The Victoria Naturalist, July / August, 1989
We published a list of birds (14 species) that had been identified this past spring in the southeast corner of Beacon Hill Park. To give a more complete picture of the number and variety of birds known to use this area, we now include the following list of species recorded in the Southeast Wood on the Christmas Bird Counts of 1984-1988. This list was compiled by John Cooper of the Royal British Columbia Museum.
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