Crop Tree Enhancement

Ames Staff, University of Tennessee scientists are examining an innovative approach to forest management that concentrates release and fertilization treatments on a limited number of crop trees within a stand. The study is large including more than 1,500 crop trees across a number of sites and species. The research was initiated with help from the U.S. Forest Service Experiment Station at Stoneville, Mississippi.

The research project has reached a 10-year benchmark and graduate students have examined growth response and the economic realities of the system. Initially, fertilization and release treatments increased second year diameter growth at breast height as much as 70% over control plots.

A thesis by Scott Twillman, a graduate student at the University of Tennessee, reported that the highest economic gains were in fertilization treatments. However, any release treatment of the crop trees resulted in very significant growth gains.

Continued analysis of the study is underway. Of particular interest is how the accelerated grow of white oaks into veneer affects economic models. Additionally, the aftermath of a major ice storm that hit the study during the first year of the study, creates opportunity to study risk analysis. Additionally, potentially negative effects, such as epicormic branching, are being closely monitored.

The technique may have high potential for application on public lands where multiple priorities vie for consideration. On private lands, landowner objectives such as monetary, wildlife and aesthetic priorities can be combined in a management strategy. This technique provides one piece in a management strategy for hardwoods. Combined with outplanting of improved seedlings from Ames’ orchard programs, a holistic program that can be likened to precision agriculture. Elsewhere on this website is the description of a concept labeled “Precision Forestry.”