Limits on Ecological Forest Management

Ecological forest management is not yet practiced every where in the world and limitations to its widespread application remain. Limitations include incomplete knowledge of the: effects of climate change on terrestrial ecosystem; life histories of previously noncommercial tree species and other plants and animals; the competi tion-density dynamics of mixed species forests; and the appropriate scale at which to measure ecosystem responses to silvicultural treatments. Also lacking is eco nomic knowledge about the total value of benefits derived from forests and about ways to evaluate tradeoffs among various goods and services.

Barriers also limit the application of existing knowledge. For example, the technology to apply variable density sil vicultural treatments could exist yet be cost prohibitive for a site. Depending on product markets, for example, in the temperate rainforest of North America, Douglas fir trees can be harvested from steep slopes using helicopter systems, but not western hemlock. The reason is not technological but financial; products from hemlock are not sufficiently valuable to offset the costs of a helicopter system. The potential effect of wood prices on management options is illustrated by red alder, a deciduous tree in these predomi nantly coniferous forests. For decades, alder was not favored by forest management objectives that emphasized softwood production and so it was eradicated. But alder confers eco logical benefits to a site because it has specialized roots that render atmospheric nitrogen available to other plants. In ecological forest management, alder retention also contri butes structural and compositional diversity that is now valued for bird and other wildlife habitat. As markets for its wood have been developed, more options exist for main taining it in a forest.

Other barriers to application can be political, social, and financial. Lack of forest land ownership, property rights, and tenure laws can discourage management planning that extends over decades and centuries. Politicians, not fores ters, set policies that directly or indirectly affect forest management, and political time horizons are commonly shorter than ecological ones. Further, tax policies affect forest management by influencing investments. Incentives that favor investment in regeneration and harvesting phases over intermediate treatments can make ecological forest management difficult to accomplish. Global and regional cycles of prosperity and poverty, peacetime and war influence priorities for ecological forest management and the resources dedicated to it.

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