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heavily by grazing cattle that tended to concentrate and remain because of lush forage and • ease of movement compared to the adjacent steep and often shrub-tangled slopes. As a result of excessive grazing in these sites, not only were weeds such as hound's tongue, Canada thistle, bull thistle, and tarweed prone to become abundant, but low-growing spreading natives such as Agassiz bluegrass and western yarrow developed extensive cover. Tall, unpalatable (orbs such as cutleaf cone(lower and stinging nettle also tended to be abundant in many of the mesic drainage sites, as a result of excessive cattle grazing. These evidences of abusive grazing practice are all too common in northwest Colorado in general. Included within the Mesic Drainage vegetation type in the Yoast study area were infrequent small areas of sedge/rush wetland, described previously. These areas were supported by local seeps and were widely encountered in nearly identical form throughout the region. The aquatic and hydrophytic species of the occasional stock ponds that existed in the area were varied and not completely predictable. Of course, some stockponds were so heavily trampled that virtually no wetland vegetation could persist unless the cattle were to be removed or greatly reduced in number. The Improved Pasture -Subirrigated vegetation type of the Yoast baseline and supplemental • study areas was located in topographic positions occupied elsewhere by the Mesic Drainage type. As mentioned above, the greater abundance of water and deeper soils in these areas have historically attracted attempts to establish cultivated fields or livestock pasture. While most of the smallest of these areas have been abandoned, the remnant domesticated grasses persisted, as discussed above. A portion of the area in the southwest corner of the Baseline Study area designated as Improved Pasture -Subirrigated has apparently had active agricultural management in the past twenty years and parts have been occasionally mowed for hay production. As a pasture for hay production, this type as it presently exists in the Yoast study area is locally somewhat deter'arated, however. The occasional abundance of Canada thistle, hound's tongue, and dandelion suggest this deterioration. However, the planted intermediate wheatgrass, redtop, smooth brome, tall fescue, and timothy were still abundant, as was the native Agassiz bluegrass. The latter, so abundant in the native drainages has reasserted a strong presence since the introduced species were planted. The Alkali Meadow vegetation type corresponds to the SCS Salt Meadow range site description (No. 265) for the Southern Rocky Mountains Land Resource Area (LRA 48). This vegetation • type corresponds only generally to any entity in Baker (1982), presumably someplace in the 'Agroovron smithii (Pascopyrum smithiil' series. This vegetation type should 25