Azafenidin (AZ), pendimethalin, simazine, and sulfometuron (SF) were applied alone and in combination to black cherry, black walnut, eastern white pine, flowering dogwood, northern bayberry, northern red oak, Siberian crabapple, white ash, white oak, and yellow poplar seedlings grown for 2 yr in the field. There were significant differences in diameter, height, and stem volume among the treatments for every species after the third growing season. Tillage significantly increased tree growth over controls for most species. No single herbicide treatment ranked best for all tree species but comparison of the mean ranks of the treatments for all species indicated that AZ resulted in the best growth. Post–bud-break applications of SF and AZ were no better than untreated controls for most species. Herbicide treatments did not affect tree survival over years but exhibited potential for better growth in establishment years.

Leafing phenology of two dry-forest sites on soils of different depth (S = shallow, D = deep) at Shipstern Reserve, Belize, were compared at the start of the rainy season (April–June 2000). Trees ≥ 2.5 cm dbh were recorded weekly for 8 wk in three 0.04-ha plots per site. Ten species were analysed individually for their phenological patterns, of which the three most common were Bursera simaruba, Metopium brownei and Jatropha gaumeri. Trees were divided into those in the canopy (> 10 cm dbh) and the subcanopy (≤ 10 cm dbh). Site S had larger trees on average than site D. The proportion of trees flushing leaves at any one time was generally higher in site S than in site D, for both canopy and subcanopy trees. Leaf flush started 2 wk earlier in site S than site D for subcanopy trees, but only 0.5 wk earlier for the canopy trees. Leaf flush duration was 1.5 wk longer in site S than site D. Large trees in the subcanopy flushed leaves earlier than small ones at both sites but in the canopy just at site D. Large trees flushed leaves earlier than small ones in three species and small trees flushed leaves more rapidly in two species. Bursera and Jatropha followed the general trends but Metopium, with larger trees in site D than site S, showed the converse with onset of flushing 1 wk earlier in site D than site S. Differences in response of the canopy and subcanopy trees on each site can be accounted for by the predominance of spring-flushing or stem-succulent species in site S and a tendency for evergreen species to occur in site D. Early flushing of relatively larger trees in site D most likely requires access to deeper soil water reserves but small and large trees utilize stored tree water in site S.