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A profile board adapted to sand shinnery oak communities gave highly accurate structural profiles of the vegetation. Using actual estimates of percentage screening of strata by foliage was more accurate than using percentage screening classes. The procedures used to adapt the profile board to sand shinnery oak communities can be used in other plant communities.

A S-year study was conducted to determine the effects of soil disturbance on plant succession and the relationship between plant succession and mycorrhizal inoculum potential (MIP) in a big sagebrush-grassland vegetation type. Disturbed plots, consisting of 4 levels of soil disturbance, were established in 1976,1977, and 1979 to evaluate environmental fluctuations. Perennial grass canopy cover and aboveground biomass production were positively correlated with MIP and negatively correlated with disturbance treatments. AMual forb canopy cover (primarily nonmycorrhizal species) and aboveground biomass were negatively correlated with MIP and positively correlated with level of soil disturbance. Weather fluctuations had a greater effect on annual plants than perennial plants after the perennial species were established. MIP values appeared to be a general indicator of the type and rate of plant succession that will evolve following soil disturbance. Above-and belowground ecology of plant communities are interacting segments of the successional process. Though not generally realized, belowground biomass in grasslands may constitute 85% of the entire community (Clark 1975

A revegetation technique study was established in a disturbed sagebrush-juniper community in northwestern Colorado in the fall of 1976. The purpose of the study was to identify effective cultural practices for establishing diverse and productive plant communities on disturbed soils. A combination of 4 treatments was applied:(1) altering life form seeding ratios, (2) seeding mixtures, (3) fertilizer, and (4) irrigation. After 4 years there was no significant difference in aboveground biomass production and canopy cover between irrigated and nonirrigated treatments. Fertilization increased production of grasses and shrub growth but depressed forb growth somewhat. The aboveground production of native and introduced mixtures was similar following four growing seasons. In general, introduced grasses out-produced native grasses, introduced forbs produced more than native forbs, and native shrubs out-performed introduced shrubs. Altering ratios among life forms affected shrub biomass more than forb and grass production. The use of different seeding rates indicates that phmt community composition will change and may be a function of not only seeding rates hut also plant and environmental factors over time and space.