Showing papers by "Thomas T. Veblen published in 1975"

Alien weeds in the tropical highlands of Western Guatemala.

Abstract: A partial comparison of the alien weed floras of California and Guatemala indicates that approximately 200% of the alien weed species of California are present in Guatemala. The vast majority of these species are present in the western highland region of Guatemala which is characterized by a native vegetation that physiognomically and floristically is remarkably similar to that of California. The large-scale introduction of alien weeds to Guatemala probably began in the sixteenth century at the time of introduction of European grains and livestock. In contrast to California, the introduced annual species have not displaced the native bunchgrasses of the western highlands. The lack of replacement of the bunchgrasses by alien annuals in the western highlands of Guatemala may be a reflection of: (1) the less acute dry season; and (2) the predominance of sheep rather than cattle in the livestock population.