Tall Fescue Online Monograph

Abstract

Tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] is one of the most widely grown temperate, perennial grasses in the world. Its adaptation and suitability are limited by extremes of temperature, soil water availability, and physical and chemical aspects of soils. Adaptation refers to the ability of tall fescue to persist through the normal fluctuation of environmental conditions prevailing in an area, while suitability for tall fescue refers to its potential to contribute significant annual yield to plant communities managed for forage within an area of adaptation. Traditional approaches to plant species suitability mapping have been based on hand-drawn maps involving a graphic artist and a plant specialist to define qualitative, highly generalized zones using minimum temperature as the primary criterion. Advanced spatial analysis approaches involving Geographic Information System (GIS) software now allow creation of quantitative, highly detailed and increasingly accurate species suitability maps based on biophysical characteristics of the region and plant characteristics. Sophisticated climate modeling software (PRISM; http://prism.oregonstate.edu/, verified 19 Mar. 2010) was used to create climatic grids for the United States and China, and digital soils information for these areas was integrated into a mapping application. Thus, data for these countries provide a demonstration of a new approach to species suitability mapping. The approach is described in this chapter, demonstrating the process of developing landscape-level tall fescue suitability maps based on published and expert estimates of climatic and soil factor tolerances for tall fescue used as forage.

Keywords: climate, edaphic, geography, GIS, persistence, soil, mapping techniques, computer mapping, PRISM, spatial analysis modeling.

Abbreviations: CIRAD, Centre de Coopération Internationale en Recherche Agronomique pour le Développement; GIS, geographic information systems; PRISM, Parameter‑elevation Regressions on Independent Slopes Model; STATSGO, State Soil Geographies; UNEP, United Nations Environment Programme.