Tropical savanna

Stock density: 300 dry cows on 1/4 acre (1/10 ha) for 30 minutes provide very high animal impact -- essential in these high-productivity areas to get standing growth grazed down or trampled before the next growing season. In my experience it's nearly impossible to impact this sort of country too much.
 

Growing season: Abundant rainfall combines with warm temperatures to create terrific growing conditions and very high biological productivity. Plant growth is so fast during the rainy season that it's far more challenging to maintain pasture quality than to prevent overgrazing of plants.
 

Dormant season: With such favorable conditions during the growing season, abundant plant material accumulates rapidly, and heavy rains create an algae-covered cap quickly on exposed soil. If those plants and soils aren't disturbed during the following dormant season, they are a major liability when the next growing season arrives. Here the area to left has been grazed at very high density; area to right has not. A one-strand electric fence separates them.

Soil surface in dormant season. The huge bulk of organic material produced every year guarantees an abundant supply of litter-making material. It takes a lot of animal impact to knock down this much dead growth. If left standing, it would shade the resprouting grasses.