Botswana Journal of Agriculture and Applied Sciences
The objective of the study was to determine the effects of season and intensity of clipping using simulated browsing on suckers' (Populus tremulaides Michx.) basal area growth on Cedar Mountain, Southern Utah, Western United States of America. Three randomly selected stands measuring 70 m x 70 m were clear-felled in mid-July, 2005, and fenced. Simulated browsing treatments of 0%, 20%, 40%, and 60% removal of current year's growth on aspen suckers were randomly applied in early, mid-, and late summers of2006 and 2007 on permanently demarcated quadrats. Sucker basal area was monitored by measuring basal diameter of individual suckers. These basal diameter measurements were then converted to m2/ha for each quadrat assuming circular diameter of individual suckers. All data for basal area was analyzed as a three-way factorial in a split-split plot design using the MIXED procedure of SAS. Basal area growth for early (172%±24%) summer treated plots was significantly (P<0.05) higher than for mid- (60%±20%) and late (70%±20%) summer treated plots that did not differ, between 2006 and 2007. Change in basal area growth for intensity 0% (1.94±0.31 m2/ha) was higher (P<0.05) than for 20% (0.78±0.31 m2/ha), 40% (0.21±0.31 m2/ha) and 60% (0.36±0.31 m2/ha) in 2006. Browsing in IT!id- and 'late summer the year following clear-felling operation would result in reduced sucker basal area growth of the suckers than browsing in early summer. Grazing programs that ensure use the first month of the growing season the year following clear-felling operation would ensure increased sucker basal area growth.
Tshireletso, K.; Malechek, J.C.; Bartos, D.L. 2010. Basal area growth for aspen suckers under simulated browsing on Cedar Mountain, southern Utah, western United States of America. Botswana Journal of Agriculture and Applied Science. 6(2):71-76