Deducing the origin of early 20th century introductions of Pinus taeda into
Zimbabwe is possible given microsatellite markers and clear population dif
ferentiation in ancestral U.S. populations. This study was designed to dete
rmine whether P. taeda introductions into Zimbabwe came from one U.S. regio
n or whether the present-day population is an admixture of introductions fr
om east and west of the Mississippi River Valley. Principal components anal
ysis, Cavalli-Sforza and Edwards' chord distances and presence of diagnosti
c alleles each indicate that the Zimbabwe population is an admixture. There
were five novel alleles in the Zimbabwe population not represented in the
indigenous U.S. populations, possibly because of de novo mutation, introgre
ssion with other introduced North American pines or sampling error.