Development of forest structure on cleared rainforest land in eastern Australia under different styles of reforestation

Rainforests in eastern Australia have been extensively cleared over the past two centuries. In recent decades, there have been increasing efforts to reforest some of these cleared lands, using a variety of methods, to meet a range of economic and environmental objectives. However, the extent to which the various styles of reforestation restore structure, composition and ecological function to cleared land is not presently understood. In this study, we develop and apply a method for quantifying the structural attributes of reforestation sites in tropical and subtropical Australia. The types of reforestation studied were plantation monocultures, mixed-species cabinet timber plots, diverse restoration plantings and unmanaged regrowth. Two age classes of reforestation were examined: 'young' (5-22 years), incorporating sites from all categories, and 'old' (30-70 years), in which only monoculture plantations and regrowth were represented. A total of 104 sites were surveyed including reference sites in intact rainforest and pasture. Intact rainforest was characterised by a suite of complex structural features including abundant special life forms (vines, epiphytes, hemi-epiphytes and strangler figs), a dense stand of trees in a range of size classes, a closed canopy, a shrubby understorey and a well-developed ground layer of leaf litter and woody debris. These features were lost on conversion to pasture. While all types of reforestation returned some elements of structural complexity to cleared land, young plantation monocultures, cabinet timber plots and young regrowth had a relatively simple structure. These sites typically had a low density of woody stems, a relatively open canopy and grassy ground cover, and lacked large trees, coarse woody debris and most special life forms. Restoration plantings and old regrowth were more complex, with a high density of woody stems, a relatively closed canopy and shrubby understorey. Old monoculture plantations in the tropics had acquired many of the structural attributes of intact forest, however this was not the case in the subtropics, where plantations were subject to more intensive management. The marked differences in structural complexity between sites suggest that the different types of reforestation practiced in eastern Australia are likely to vary considerably in their value as habitat for rainforest biota. (C) 2003 Elsevier Science B.V. All rights reserved.

The importance of considering social issues in reforestation schemes

This paper reports the results of a survey of north Queensland landholder attitudes with respect to a number of issues relating to participation in forestry. The survey explored the reasons why landholders plant trees, perceived obstacles to greater farm forestry, and attitudes to tree planting programs such as the Community Rainforest Reforestation Program (CRRP) and Private Joint Venture Scheme (PJVS). The results of the survey are discussed in the context of possible policy prescriptions that can be made at local, state and federal government levels to facilitate greater tree planting in the region. Many of the problems faced by local landholders are shared by landholders in other parts of Australia and throughout the world. This survey can thus serve as a case study, providing information on a number of issues concerning small-scale forestry policies that are of general relevance to the development of farm forestry programs.

Economic issues and lessons arising from the community rainforest reforestation program

A large number of socio-economic research projects have been conducted in north Queensland which have drawn on observations from, or been otherwise inspired by, the Community Rainforest Reforestation Program (CRRP). The research may be considered under the headings of financial performance of farm-grown timber, externalities (or environmental values), impediments to tree planting on farms, analysis of the timber supply chain including timber marketing, and facilitation of forest industry development. This paper summarises a variety of insights generated by the research, on small-scale forestry based on native tree species and on policy measures which may be adopted to promote tree growing on farms in tropical north Queensland.