Field and greenhouse studies were conducted in 1986 and 1987 to determine the impact of disturbance of microphytic soil crust on emergence of two warm season grass species. In the greenhouse, emergence of seedlings sown on the top of undisturbed crust, under the crust, on disturbed crust, and on bare soil was studied. The mean number of seedlings of "Cochise" lovegrass (Eragrostis lehmanniana x Eragrostis tricophora) and Kleingrass (Panicum coloratum) was higher on disturbed field plots than undisturbed plots. Disturbance reduced the microphytic crust cover, and the crust did not recover throughout the growing season. Presence of seedlings in samples of litter washed off the plots and observation on ants showed that all the seeds sown did not remain on the plots during the growing season. In greenhouse flats the emergence of seedlings of both species was greater on disturbed microphytic crust and bare soil than when seeded on top of or under an intact crust. Undisturbed crust restricted penetration of roots and shoots when seeds were placed on or under the crust.