Method Narrative  |
From Houston et al. 1994: "Plant communities were sampled with plots similar to those described by Franklin et al. (1971a) and Henderson et al. (1989) for forest vegetation. We used relatively small, variable- sized plots (20-100 m2) because extensive areas of homogeneous vegetation were uncommon at high elevations in the Olympic Mountains. The generally rectangular or square plots were located in vegetation that typified plant communities in the vicinity. Evidence of herbivore activity was not used as a criterion for locating individual plots, and plots were never placed near sites where salt had attracted mountain goats (Oreamnos americanus; see below).
Variables recorded included plant cover by species, substrate characteristics, slope, aspect, and elevation. Cover was estimated in classes of trace and percent ages of <1, 1-5, 6-25, 26- 50, 51-75, 76-95, and 96-100. Small cover classes at each end of the scale prevented overestimates of species with low cover and underestimates of species with extremely high cover. The same classes were used to estimate cover of mosses, lichens, litter, organic matter, bare soil (<2-mm particles), total rock, bedrock, and five size classes of loose rocks (diameters of >2 mm—4 cm, 5-10 cm, 11-20 cm, 21-70 cm, and >70 cm)."
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