Studies of thirteen clones of Rhus glabra, the smooth sumac, yielded information on height, age, imcomplete development of twig, branching angles, size of clone, average annual growth, direction of growth, numbers of stems of each age class, and location of new growth. One clone was partially excavated, and one clone showing considerable mortality of upper twigs was studied. The major conclusions drawn are: 1) the stems range in height from 0.4 m to 3.0 m and in age from one to fifteen years; 2) the tallest stems tend to be the oldest; 3) of the buds observed, 56% did not undergo complete development to the stage of flowering or fruiting; 4) branching angles differ significantly from clone to clone; 5) one clone has been shown to be a vegetative development of one individual; 6) the area covered by one clone may be as much as 22 by 40 m; 7) average annual spread of a clone is 94 cm per year; 8) the pattern of growth is one-sided; 9) the number of new stems varies from year to year; 10) the percentage of new stems which occupy territory outside the previous clonal boundary tends to decrease in successive years; 11) a stem may arise from a rhizome several years old; 12) one clone was found to be dying in the center.