The black walnut financial model is a simplified decision model. It is designed to assist potential growers in making decisions about tree spacing, nut harvest, and whether to use improved (grafted) or unimproved trees. The model does not claim to accurately show tree growth characteristics at future points in time. However, it does use a simple algorithm to make estimates about future nut production and tree diameters. The model should be used to consider how certain management decisions, i.e. tree spacing, will affect the financial performance of the plantation in terms of potential increases and decreases in net present value, internal rate of return and annual equivalent value.
Research on willow (Salix spp.) as a locally produced, renewable feedstock for bioenergy and bioproducts began in New York in the mid-1980s in response to growing concerns about environmental impacts associated with fossil fuels and declining rural economies. Simultaneous and integrated activities "including research, large-scale demonstrations, outreach and education, and market development" were initiated in the mid-1990s to facilitate the commercialization of willow biomass crops. Despite technological viability and associated environmental and local economic benefits, the high price of willow biomass relative to coal has been a barrier to wide-scale deployment of this system. The cost of willow biomass is currently $3.00GJ -1 ($57.30 odt -1) compared to $1.40-1.90GJ -1 for coal. Yield improvements from traditional breeding efforts and increases in harvesting efficiency that are currently being realized promise to reduce the price differential. Recent policy changes at the federal level, including the provision to harvest bioenergy crops from Conservation Reserve Program (CRP) land and a closed-loop biomass tax credit, and state-level initiatives such as Renewable Portfolio Standards (RPS) will help to further reduce the difference and foster markets for willow biomass. Years of work on willow biomass crop research and demonstration projects have increased our understanding of the biology, ecophysiology and management of willow biomass crops. Using an adaptive management model, this information has led to the deployment of willow for other applications such as phytoremediation, living snowfences, and riparian buffers across the northeastern US.
By T.A. Volk, L.P. Abrahamson C.A. Nowak, L.B. Smart, P.J. Tharakan and E.H. White Biomass and Bioenergy Volume 30, Issues 8-9, August-September 2006, Pages 715-727
The energy efficiency and economic benefits of agroforestry systems are key issues with respect to their actual sustainability as sound agricultural practices as well as to their potential for further development. Two typical agroforestry systems in China, the Paulownia (Paulownia elongta S.Y. Hu) intercropping system in the north and the Tea (Camellia sinensis O. Ktze) intercropping system in the south were chosen as research subjects. The studies were conducted to establish the energy balance and economic benefits to farmers of these two agroforestry systems in northern and southern China. The objectives were to determine the potential of developing the Paulownia intercropping system in the north and the Tea intercropping system in the south, and their respective sustainability.
Of the five major temperate agroforestry systems silvopastoralism is probably the least researched and understood. This compendium of papers from proceedings of an International Congress held in Lugo, Spain in 2004 fills a niche and shows that there is a lot happening in this area, especially in Europe. One paper quotes "in a case study that investigated 40 pastoral systems of all the countries of the Mediterranean basin, up to eight different forage resources were present in a single case, with an average of five." An issue in many cases is convincing farmers to integrate trees into pasture systems. As some of the papers show, many silvopasture systems are a dying legacy of long held farming practices. However, there is perhaps a bright future given the multiple environmental and economic benefits, and the opportunities silvopasture provides on marginal lands. The book is divided into 5 sessions:
Silvopastoral systems: types and main design.
Silvopastoral management, productivity and quality.
Ecological implications of silvopastoral systems: biodiversity and sustainable development.
Economical, social and cultural benefits of silvopastoral systems.
Future perspectives of silvopastoral systems in a world context.
Wisely controlled browsing of Northeast woodlands by goat herds could increase revenue and reduce costs to goat owners, decrease woody plant control costs to woodlot owners and reduce the forest area treated with herbicides. This Cornell and Penn State project was initiated to determine how to enhance meat goat production while using the goats to control woody interfering plants in mature forests. Goats were placed in mature hardwood forests, with a well-developed understory of interfering woody species (i.e., American beech and striped maple).
Rowan is a Senior Lecturer in Agroforestry at the Faculty of Land and Food Resources, The University of Melbourne. With his family he is also the owner of the Bambra Agroforestry Farm in Victoria, Australia, where he practices what he preaches.
Bambra Agroforestry Farm is our private attempt at demonstrating how multipurpose forests can be integrated into a farming landscape. More than 40 commercial timber species have been incorporated into plantings for land degradation control, shelter, fire protection, shade, wildlife habitat and beautification. Since the first trees were planted in 1987, more than 4000 visitors from across Australia and overseas have taken our guided tour around the farm and witnessed demonstrations and debates about farm forestry.