Disturbance during logging stimulates regeneration of koa

Abstract

The abundance and distribution of Acacia koa regeneration after logging were studied on a 500-acre (202-ha) tract of koa forest heavily infested with Passiflora mollissima vines on the island of Hawaii. Koa seedling density was about three times greater in disturbed areas than in undisturbed ones. Most of the koa seedlings in the sample tha t grew in response to ground disturbance during logging were established. None of those found in undisturbed areas were established. Seedlings in disturbed areas tended to be clustered near koa seed trees, with twice as many growing within 50 feet (15.2 m) of seed tree stems as beyond, Vines had just begun to climb into the crowns of oldest regeneration. They pose an imminent threat to normal growth and survival of infested trees.

Citation

Scowcroft, Paul G.; Nelson, Robert E. 1976. Disturbance during logging stimulates regeneration of koa. Res. Note PSW-RN-306. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station. 7 p