Field Guide. cropping and pastoral grazing on flat to rolling country.

PLANT INDICATORSDrought stress of pastures during dry periods Assess, from visual evidence <strong>and</strong> local knowledge, the degree towhich pastures are drought stressed during dry periods by comparingthe greenness of the pasture with the three photographs opposite. Assess the level of dry matter production, <strong>and</strong> whether droughttolerantspecies have become dominant in the pasture sward.THE DEGREE OF DROUGHT STRESS in dry periods depends on climaticconditions, the drought tolerance of the pasture, <strong>and</strong> the water-holdingcapacity of the soil. The last is governed by soil depth <strong>and</strong> texture,organic matter content, <strong>and</strong> the number <strong>and</strong> size of soil pores. Pastoralsoils with a good soil structure have a large number of macropores <strong>and</strong>coarse <strong>and</strong> medium-sized micropores, <strong>and</strong>, subsequently, have a higherwater-holding capacity than degraded soils with few pores.78 VISUAL SOIL ASSESSMENT: Volume 1