1a. Objectives (from AD-416)
Develop a decision support tool to incorporate environmental and conservation effects into forage species placement in the landscape.
1b. Approach (from AD-416)
The choice of where to use annual vs. perennial species in the landscape, and which species to use, depends on species characteristics, soil and climatic conditions, and production and conservation goals. Tools currently exist to inform placement of species based on the effects of species and site characteristics on forage production. However, expansion of these tools is needed to incorporate conservation goals into species placement recommendations. Under this objective, existing multi-species models will be identified and reviewed to determine their suitability for use in conservation planning for northeastern USA pastures. Existing forage production and conservation effects data sets will be collected and used to identify gaps in the existing tools, and research strategies for filling those gaps will be identified. This research will lay a sound foundation for development of a robust and defensible decision support tool that incorporates conservation goals into species placement.
3. Progress Report
A post-doctoral research associate was hired, and a study comparing three models developed for grassland systems was developed. The three models, ALMANAC, PHYGROW, and APSIM (two US rangeland and one Australian pasture model), were parameterized for a research farm in central Pennsylvania, and tested against several years of on-farm data on species composition and biomass. While ALMANAC and PHYGROW work well in rangelands, processes crucial to modeling temperate humid pastures are not well-characterized, in particular rotational grazing management and nutrient cycling. APSIM, designed as a pasture model, was more effective at simulating conditions on the test farm, although licensing requirements may prevent its wide adoption within the USDA. The report prepared on this work will guide the development of pasture modeling capabilities within the USDA-NRCS Grazingland CEAP context. Progress was monitored through email and conference calls.