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increase, most notably the dominant westernwheatgrass (Agropyron smithir), which increased from 6.0% cover in ] 998 to 17.0% cover in 2001. Cover ofnon-noxiousforbs declined over the course of the study (from 8.0% in 1998 to 1.0% in 2001), mostly due to reduced cover of yellowsweetclover (Melrlotus oj~cinalis), which contributed 6.0% absolute cover in 1998 and 1.0% absolute cover in 2001. Total vegetation cover appears to have stabilized at around 50%. CONCLUSIONS AND RECOMMENDATIONS Reference Area No. 1 and Adiacent Reclaimed Flat Areas in Sutev Pile Vicinity CONCLUSIONS • Control program objective appeazs to have been met. Within the sampled reference azea, density of noxious weeds declined by over 85% between 1998 and 2001. • A satisfactory vegetation cover has developed~ominated by perennial grasses. • Perennial forb cover declined significantly between 1998 and 2001, but a number of desirableforb species aze present in the stand, at low levels, • The biennials plumeless thistle and houndstongue are the primary noxious species remaining in the stand, although at much lower levels than prior to initiation of control. A spazse scattering of Canada thistle plants remain, at a level not detected by cover sampling. TIONS • Suspend formal monitoring unless conditions change. Perform informal visual reconnaissance monitoring late May/eazly June each yeaz. • Suspend chemical control with the exception of fall spot spraying of defined patches of Canada thistle noted during annual visual reconnaissance. • Consider continued mechanical control to prevent seed production of remnant noxious plants by chopping with weed whip or other appropriate hand tools annually in late June/early July, possibly as part of an organized goup activity. • Document control efforts annually. Reference Area No. 2 and Adjacent Sutev Pile Slone Areas CONCLUSIONS • The noxious weed reduction objective of the control program appeazs to have been met. Within the sampled reference azea, noxious weed density declined by approximately 75% between 1998 and 2001: Most of the decline appeazs to reflect reduction of the initially dominantplumeless thistle and other biennial species, with minimal impact to Canada thistle. • Several noxious species, including the perennial Canada thistle, and the biennialsplumeless thistle, bull thistle, and houndstongue maintain a significant presence in the stand.