• Simulated Cattle Injury to Planted Slash Pine: Combinations of Defoliation, Browsing, and Trampling

      Lewis, C. E. (Society for Range Management, 1980-09-01)
      Cattle injure young pines by defoliating, browsing, and trampling them. Little is known about how these injuries at various levels and in various combinations will affect survival and growth of planted pines. Therefore, such injuries were simulated once on slash pine at 6, 18, and 30 months after planting by (1) hand clipping to remove needles, (2) clipping off the shoots, and (3) bending the stem at a right angle to the vertical. Survival was poorest when treatments were applied to seedlings within 6 months after planting, whereas mortality was low when older seedlings were treated. Only the severest treatments, especially combinations of injury, caused extreme mortality. Seedlings treated at 6 months after planting suffered greater reductions in height growth than did the older seedlings. Only the severest combinations of injury permanently reduced height growth.
    • Simulated Cattle Injury to Planted Slash Pine: Defoliation

      Lewis, C. E. (Society for Range Management, 1980-09-01)
      Animals sometimes injure trees by eating the leaves. Little is known about the amount of removal required to harm survival and growth, particularly of southern pines. To simulate a single defoliation by livestock or wildlife, needles of slash pine were hand clipped once at 6, 18, and 30 months after planting. Survival and height growth were measured for six growing seasons after removing 0, 25, 50, 75, and 100% of the foliage. Survival was excellent except when 100% of the needles were removed 6 months after planting. Reductions in rate of height growth occurred only with the most severe levels of defoliation and were still apparent for 3 years after treatment. Even so, the greatest accumulated loss in height was less than 1 m over the 6-year period.
    • Simulated Cattle Injury to Planted Slash Pine: Girdling

      Lewis, C. E. (Society for Range Management, 1980-09-01)
      Animals are known to girdle, or partially girdle, trees and shrubs by eating the bark or by knocking off the bark with their hooves. Since girdling has been observed in slash pine plantations being grazed by cattle, this form of injury was simulated on three ages of slash pine. Survival and growth were observed for 6 years after removal of a 5.1-cm-wide band of bark from around 50, 75, and 100% of the stem near groundline. Mortality was negligible except after complete girdling; even then, some seedlings lived. Height growth was reduced by the 75% girdle, primarily on seedlings treated within 6 months after planting. Two side tests on 100% girdles helped explain how trees can survive this severe injury.