Growth promotion induced by herbivory has been frequently reported and termed overcompensation. Overcompensation in browsed plants ultimately results in enhanced development as compared to intact plants. This promotion of growth can suspiciously resemble the breaking of apical dominance. A complicating factor in the activation of axillary shoots following decapitation is nutrition. To investigate influences of decapitation, terminal stem apices were excised from plants in one of three ways: 1) at the middle of the first or basal internode, 2) at the middle of the second internode, and 3) immediately subjacent to the apex itself. Nutritional influences were examined by removing one of the two basal unifoliate leaves from one-half of the plants. Stem apex and leaf removal occurred when Phaseolus aureus plants were thirty days old. Plants were monitored for vegetative and reproductive development for the next two months. Axillary shoot formation was negligible in intact plants. Most axillary shoot elongation took place early in treated plants during the sixty day monitoring period. Treatment plants exhibited differences in: 1) axillary shoot number, 2) individual length of axillary shoots, 3) combined axillary shoot length per plant, and 4) the length of fruit-bearing axillaries. Intact and experimental plants revealed differences in above-ground height as well as pod length. However, pod mass was similar in control and treatment plant groups. Stem apex removal was considered more influential than leaf excision in the promotion of axillary shoot development.

Key words: Phaseolus aureus , apical dominance, axillary shoots, decapitation, overcompensation