Controlled experiments on soil compaction produced by off-road vehicles in the Mojave Desert, California.
Vehicle tracks were made by up to 100 motorcycle and four-wheel drive passes in the Mojave Desert of California on a Typic Haplargid and a Typic Torripsamment soil. Soil strength increased with increasing number of passes, down to 25 cm depth. The four-wheel drive vehicle produced greater increases in soil strength than the motorcycle, and increases were greater on wet soil than on dry soil. Soil strength increased at a greater rate in drying compacted soil than in drying uncompacted soil. The relationship between soil compaction and reduced growth of desert annual plants is discussed.