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In the 17 years following chemical brush control of a 40-acre big sagebrushbunchgrass range, grazed during or after seed maturity of the principal grasses, yearling days of grazing increased 1.9 times as much and per acre beef gains were 2.3 times that prior to brush control. Total herbage production averaged 227 lb./acre prior to treatment and 681 lb./acre in the years following treatment. The internal rate of return derived from the beef returns of this study and estimated costs was in excess of 50%. Brush return was slow during the first decade following treatment but is now rapidly approaching pretreatment numbers and dispersion characteristics.

Mineral analysis of forage from a nitrogen (N) fertilizer, field study produced unexpectedly high iron (Fe) concentrations which were correlated with the N fertilizer level (r2=.92) and the percentage N in the forage (r2 =.94). The high Fe values were presumed to be associated with dust on the leaves. The objective of this study was to determine the level of soil contamination on the forage sample and the contribution of mineral in the contaminant to that measured in the sample. Soil contamination of plant tissue samples was calculated from the dilution of soil titanium (Ti) assuming that the uncontaminated tissue contained 0 g Ti/g. Tissue harvested from the 0, 28, 56, or 84 kg N/ha treatments contained 23, 49, 48, and 60 mg soil/ g, respectively. Significant N fertilizer effects would have been accepted for each element tested if soil contamination had been ignored. Correcting for contamination resulted in significant N-fertilizer effects on the concentrations of sodium, potassium, manganese, iron, and zinc but not magnesium or calcium in the forage. Some of these effects may be explained by the acidifying effect of the N fertilizer source.