| Title: | Responses of native and invasive plant species to selective logging in an Acacia koa-Metrosideros polymorpha forest in Hawai'i. |
| Authors: | Friday, J.B.
Scowcroft, P.G.
Ares, A.
USDA, FS |
| Source: | Applied vegetation science. 2008 Dec., v. 11, issue 4, p. 471-482. |
| NALT Subjects: | Acacia koa
Metrosideros polymorpha
Fraxinus uhdei
forest trees
forest plantations
invasive species
woody weeds
logging
forest thinning
basal area
roads
Passiflora
introduced plants
Poaceae
seedlings
natural regeneration
canopy gaps
soil fertility
tropical forests
Hawaii |
| Other Subjects: | Erharta stipoides
Passiflora tarminiana |
| Issue Date: | Dec-2008 |
| Abstract: | Questions: Is the introduced timber species Fraxinus uhdei invasive in Hawai'i? Has logging disturbance facilitated the spread of Fraxinus and other alien species? Location: Windward Mauna Kea, island of Hawai'i. Methods: We surveyed 29 plots which were established before selective logging of the native tree Acacia koa in 1971 to determine if Fraxinus spread beyond the borders of an existing plantation and if other alien species increased. We created gaps in the canopy of the Fraxinus plantation and measured seed rain and regeneration, and we sampled foliar and soil nutrients inside and around the plantation. Results: Basal area of Fraxinus increased from 0.7 m2.ha-1in 1971 to 10.8 m2.ha-1 in 2000. Fraxinus was not found in plots that were located more than 500 m from those where it occurred in 1971 except along a road. Basal area of Acacia koa decreased after logging but subsequently recovered. Occurrence of the alien vine Passiflora tarminiana and alien grass Ehrharta stipoides decreased. Seedling regeneration of Fraxinus was prolific in gaps but did not occur under the canopy. Basal area of Fraxinus did not correlate with soil nutrient concentrations. Conclusions: Fraxinus was able to regenerate following logging more rapidly than native tree species. Basal area growth of Fraxinus was great enough to offset a decline in native trees and cause an increase in forest productivity. If the Fraxinus plantation is harvested, managers should plan ways of favoring regeneration of the native Acacia which is more valuable both for timber and for conservation. |
| URI: | http://hdl.handle.net/10113/29733 |
| Appears in Collections: | USDA Research and Information
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