| Abstract | A project to evaluate Thematic Mapper data for range management applications in rough fescue grasslands was started by the Canada Centre for Remote Sensing (CCRS) in 1984. The project was a joint effort
between CCRS, the Alberta Public Lands Division of the Department of Forestry, Lands and Wildlife, and the Alberta Remote Sensing Centre. Ground and satellite data were collected for the Waldron Ranch in 1984 and the Waldron and a7 Ranches in 1985,
two areas of rough fescue prairie (Festuca scabrella). The evaluation was carried out in three parts. First, a quantitative analysis compare digital numbers for six TM bands with ground data parameters, such as the ratio of green and brown
vegetation, weights of grass, forbs, and litter, and percentage desirable species. Second, a qualitative analysis was carried out to determine which three TM bands and colour assignments were most favoured for range assessment. A third step was a
practical field evaluation of the favoured image product. TM bands were positively correlated with the percentage of brown vegetation on late spring images for all bands except TM4. Conversely, the percentage of green vegetation was inversely
related to all bands except TM4 on late summer images. These correlations appeared to relate to seasonal changes in plant phenology. No quantitative relationship was defined between the TM bands and the other parameters of biomass and percentage
desirable species. Although the quantitative analysis was favoured the TM 4, 3, 5 or TM 4, 3, 7 enhancements for visual interpretation of rough fescue rangeland. The field evaluation confirmed the value of TM 4, 3, 7 colour composites as both a range
vegetation map and a source of information on grazing management. This image product will assist range managers to quickly and efficiently identify foothill rangelands that may be heavily grazed so that corrective management might be initiated.
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