Grassland or Open

Healthy grasslands grow a diverse community of native bunchgrasses and forbs. Natural grassland habitats seldom occur in the Swan Valley because enough rain and snow fall annually to grow thick forests that shade out grasses. At MPG North, healthy grasslands are absent from the landscape at present. Commercial timber and real estate development created numerous open habitats that attract some grassland-associated wildlife, like elk (Cervus canadensis), American kestrels (Falco sparverius), eastern kingbirds (Tyrannus tyrannus), tree swallows (Tachycineta bicolor) and western meadowlarks (Sturnella neglecta). We plan to manage these open areas for establishment of native grassland plant species. Unhealthy grasslands exist in the Swan Valley where established by human disturbances. Some cleared areas, now used for livestock grazing, will remain free of trees as long as grazing persists. Roads, log decks, and clearcuts with compacted soils and applications of exotic sod grass seeds also inhibit tree growth. At MPG North, previous real estate managers dredged wetland areas to create open ponds. They spread the dredged soils over clearcut areas and seeded them with exotic grasses like meadow timothy (Phleum pratense) and meadow grass (Poa spp.). These grasses thrive on the wetland soil and prevent tree establishment, but exotic invasive forbs like Canada thistle (Cirsium arvense), oxeye daisy (Leucanthemum vulgare), and spotted knapweed (Centaurea stoebe) gain footholds in wetter areas of the fields. Seeds from the grasses and exotic forbs persist in the seedbank and guarantee future generations of this unusual habitat type.

Some wildlife species favor open spaces in the Swan Valley, but few appear to benefit from the mix of exotic grasses and forbs that grow in fields at MPG North. We define "fields" as unhealthy open areas with exotic grasses and forbs that suppress tree growth. The desired future condition is habitat dominated by bunchgrasses and forbs that provide greater nutritional benefit to wildlife than the unhealthy fields did. Natural succession to trees and shrubs should occur in parts of the grassland, but managed disturbance events like fire will maintain open areas at MPG North for wildlife benefit.

We planted 1325 trees and shrubs at MPG North over the week of September 14th. This map shows all planting locations. Each plant received at least one gallon of water before exclosure installation. The planting crew applied 2.5 gallons of wood chip mulch over plant roots in dry areas (shown in orange) to improve water retention and decrease grass competition. Mulch applications to island plantings depended on experimental treatment.

Our August 2011 invasive weed survey began with the need for baseline data and it being a 'banner year' for growth- thus a good time to collect data. QUsetions we aim to answer with the survey include; What is the current distribution and abundance of three widespread asteraceous species (Canada thistle - CIAR, spotted knapweed - CEMA, oxeye daisy - LEVU) on MPG North? Is weed distribution similar among the target species? What other weeds exist on the property, and where are they? Are weeds invading relatively undisturbed areas? 


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