Background

The aims of this project are to:

• provide guidelines for the preparation and management of seedling stock during plantation establishment;
  
  
• develop weed management systems that minimise the use of herbicides, including the use of non-competing species as cover crops;
  
  
• develop pruning, thinning and spacing systems that are suitable for converting industrial pulpwood plantations to clearwood regimes and for farm forestry;
  
  
• assess the benefits and costs of trees on farms, and the real or perceived barriers to the adoption of commercial forestry on part or all of the farm enterprise, and develop an enhanced understanding of the factors which determine regional timber supply.
  

Outcomes

• Rapid induction of cold-induced photoinhibition of E. nitens decreased photochemical efficiency and chlorophyll, and increased xanthophyll cycle conversion ratio and xanthophyll cycle pigments. Anthocyanin levels gradually increased except in non-shaded, nutrient-deprived seedlings that had high levels before the induction of photoinhibition. The findings strongly indicated that anthocyanins might provide a photoprotective role.
  
  
• Shadecloth shelters when placed around seedlings in the field to lower light intensity will alleviate cold-induced photoinhibition and maximise growth during winter, but limit growth during warmer periods and therefore overall growth.
  
  
• Eucalyptus nitens and E. globulus seedlings can adjust their leaf angle. Larger leaf angle was associated with decreased levels of incident photon flux density and also with increased levels of photoinhibition induced by nitrogen deficit. Leaf angle may play a role in photoprotection of eucalypt seedlings.
  
  
• Acacia melanoxylon (blackwood) can compensate for the removal of crown area during green pruning by increasing its photosynthetic capacity in the upper two-thirds of the crown. Form pruning that removes foliage solely from the upper reaches of the crown is likely to reduce this increase in capacity and have a greater effect than lift pruning on the growth of blackwood.
  
  
• For commercial nurse-crop species like E. nitens and Pinus radiata, closer spacing than is used conventionally can produce better blackwood form. However there is a tendency for slower blackwood growth, meaning that management of blackwood under systems such as the five-row nurse treatment must be vigilant to avoid suppression of blackwood growth.
  
  
• Lack of post-planting weed control has been a major deficiency leading to the poor success of revegetation programmes in the Midlands of Tasmania. Improved record keeping in these programmes would benefit landowners, extension officers and research scientists working in this area.
  
  
• An examination of the 'Drier Tasmanian Demonstration Areas' project indicated that it had been successful in expanding commercial plantation establishment into areas not traditionally or currently involved in the forest industries. Demonstration sites are an important element in fostering the establishment of trees on farms.
  
  
• Investment in farm forestry extension should be viewed as process for building partnerships and seeing forestry's pluralism (i.e. reliance on many and varied stakeholders) as an opportunity to engage more widely amongst communities about forestry's contribution to the social, economic and environmental fabric of society.
  

Goals

• Quantify the effects of drought and seedling size on seedling growth and mortality following planting.
  
  
• Establish four species trials and one demonstration trial in the Midlands of Tasmania using best practice techniques.
  
  
• Publish a 'Farm Forestry Technical and Business Handbook'
  
  
• Develop a process-based model of blackwood height.
  
  
• Develop a schedule for managing effluent irrigation of plantations managed for solid wood.
  
  
• Study the determinants of non-industrial private owners' timber harvest and management decisions.
  
  
• Clarify how community anxiety over forestry expansion can be replaced by cooperation between diverse stakeholders.