Optimal selection of plants for a particular use and combination of climate and soil conditions requires knowledge of plant tolerances. This section describes plant classification, principal plant families of importance for forage, soil conservation, and beautification, describes how quantitative plant tolerances can be mapped using GIS techniques, and provides links to the various plant types (grasses, legumes, forbs, and shrubs).

Classification Systems

Although there are several plant classification systems and little agreement among botanists, for the purposes of the SSIS there are relatively few classification system problems, since we are dealing only with flowering plants (angiosperms) and principally two families; grasses (Poacea, previously Gramineae) and legumes (Fabacea, previously Leguminosae). Other important forage, soil conservation, and landscape plants can be grouped into forbs and shrubs.

Carolus Linnaeus

Scientific Names

For "creating order out of the chaos"" of common names, each plant is known by its scientific name - composed of a genus and a species. The scientific name is followed by the name of the person who correctly named the species. Thus, Medicago sativa L. means that this species (with common names of alfalfa or lucerne) was name by the Swedish botanist Linnaeus.

Principal Forage Plant Families

Grasses are members of the Poaceae plant family, monocotyledonous, annual or perennial, mostly herbaceous, with jointed culms, sheathed leaves, and parallel veination.

Legumes are members of the Fabaceae plant family, dicotyledenous, annual, biennial, or perennial, with pods that dehisce on both sutures, and capable of biological nitrogen fixation when grown in association with the appropriate symbiotic bacteria.

Forbs are typically defined as herbaceous (non-woody), non-legume, dicotyledonous plants.

Trees and shrubs (woody plants) also contribute to nutritional requirements of browsing animals, reduce soil erosion and beautify the landscape.

Quantitative Tolerances
To describe accurately where each plant species (and cultivar) can be grown, quantitative tolerances must be defined for climate, soil, and pest stress factors. These values are not well established in the scientific literature, so they are being developed in this project by a combination of expert knowledge and experience and journal publication data and crop simulation research. Validation of this "best guess" approach is accomplished by gleaning information from field trial data and specific experiments designed to test values.

Maps developed by creating rules from quantitative tolerances and applying them against spatial data layers for climate and soil information are provided in this web segment for selected species. An internet map server "dynamic mapping" application is also available for creating new maps.


Order from Chaos: Linnaeus Disposes