49 



The forest ecosystem where trees are removed or destroyed under rapid climate 

 change may, in fact, not return. If the conditions for seedhng survival and success 

 are not available in the decades after the trees die, some other kind of system will 

 emerge. That system may or may not be what people need or want. Forest managers 

 need to be ready to do what it takes to restore desirable ecosystems, over larger 

 areas, with more difficulty, and higher costs. That will mean a significant increase 

 in public understanding and support, led by policymakers in Congress and the Ad- 

 ministration who understand the difficulty, and are willing to take leadership in ac- 

 quiring the necessary priority and funding to do the job. 



ECOSYSTEM RESTORATION 



The challenge posed by climate change and environmental stress, seen in the light 

 of the "new ecology" ideas, may force us to look harder at what the task to which 

 we have set ourselves when we begin to try to restore forest ecosystems. 



In the past, we would have looked at the history of the site, and tried to mimic 

 the forest system that was historically successful. Or, we might substitute a system 

 that had been proven to succeed. In many places, that still works. Douglas-fir is 

 planted on sites that supported a hemlock-fir mixture in the Pacific Northwest, and 

 Loblolly pine replaces Longleaf pine in Southern forests. In many cases, those are 



?;ood sites with excellent growth conditions, and perhaps the best successes enjoyed 

 iavorable weather for a few years. 



But the reforestation failures on many forests tell us that this can't always be 

 counted upon. And, in some places, the situation has changed so dramatically that 

 we simply can't expect an easy return to a healthy forest. Where topsoil has been 

 lost, or the lack of forest cover has changed micro-climates into harsh, dry, over- 

 heated situations, an entirely different set of challenges may be involved, and dif- 

 ferent approaches demanded. 



In those situations, ecosystem restoration may demand that we become more 

 adept at determining what can succeed on a eiven site, in light of the current and 

 future conditions likely to be critical. It may be, in many instances, that the plans 

 needed to "colonize" a degraded site may not be those that are destined for long- 

 term success. Instead, they are essential as a "bridge" to the ecosystem that can suc- 



Our Heritage Forest partners in Costa Rica, Ecuador, and Hawaii, for example, 

 are all faced with the challenge of restoring tropical forests. Primary tropical forests 

 contained hundreds of species; restoring that complexity is a tremendous challenge. 

 But there is strong evidence that it is also unnecessary. Instead, what may be need- 

 ed is to get the vertical structure of trees established, so that degraded grasslands 

 can once again become a home for the tree-climbing, tree-roosting animals and birds 

 common to the region. When those critters return, they spread the seeds of indige- 

 nous species, and a complex secondary forest begins to develop. What eventually re- 

 sults may never be exactly like the primary forest, but it can become an excellent 

 tropical forest; highly valued for its many products, goods, and services. And it will 

 be the ecosystem that has demonstrated tne ability to develop and succeed under 

 the existing conditions — a major victory compared to no forest at all. 



So our partners are planting Acacia species in many places, because it can be eas- 

 ily estabUshed, and is a successful colonizer that can compete with the coarse 

 grasses and other vegetation. It attracts the birds and tree-climbers, and thev 

 spread seed. In many places, the Acacia won't be found after 10-15 years; it will 

 have been crowded out by the profusion of native trees estabhshed on the site. But 

 it will have done its job, proviaing shade, nitrogen, and an initial structure for the 

 new forest. 



In Indiana, I have seen tree farms where the farmer has planted 6-10 species in 

 a single field. Some were planted on special areas because of soil or site consider- 

 ations. Otiiers provided early-succession shade and competition that helped longer- 

 lived trees succeed. Not all the trees — or species — will live to maturity, and the re- 

 sulting forest will have many aspects of self-selection and response to changing envi- 

 ronmental conditions. 



In Arizona, New Mexico and Oregon, riparian area forests are being re;«8tab- 

 lished as a means of restoring water flow and quaUty in streams. The species are 

 not commercial; in many areas seed or cutting must be collected from remnant 

 trees in order to get the right planting stock. The pioneer plants may or may not 

 sxirvive — a streamoank is a pretty hazardous place for a tree to try to succeed, but 

 the re-introduction of woody plants along the stream, combined with close control 

 of grazing animals and some mechanical structures to help the stream begin to heal 

 itself, are working miracles in some places to return mountain valleys to ecosystem 

 health. 



