Class 6
Vegetation Groupings

By looking in detail at the plants that occur in different areas certain patterns emerge. Certain plants frequently grow together. These groupings are related to environmental conditions and can be described in varying degrees of resolution. Ecological Vegetation Classes are a relatively new broad descriptor, Communities are a common method of describing the types of plants that may be present and sub-communities allow for further division which allows for local variations.

Vegetation groupings are usually defined in terms of the common overstorey plants, density or cover of these plants and the mixture and characteristics of other species present.

Environmental conditions (abiotic factors) and the influences of other plants and animals (biotic factors) influence vegetation groupings.
Abiotic
Soil - type, structure and chemistry
Climate - temperature, rainfall, evaporation, humidity, wind, amount of direct sunlight, seasonal variations
Location - aspect, elevation
Fire - timing, intensity, extent

Biotic
These are caused by other plants and animals and may include
Predation, parasitism, mutualism (symbiotic relationships, pollination, dispersal), competition

Ecological Vegetation Classes (EVCs)
EVCs were developed to classify groups of plants that share a range of environmental and ecological characters. ECVs are based on soils and geology, life forms, rainfall, elevation, aspect, topography and a range of other environmental characters. Floristics, or the types of plants present, is only one of the many factors taken into account.
EVCs typically cover a large area and may be used for broad management purposes, however they may not provide sufficient detail for on ground works, especially for small areas. They are ecologically based, using statistically repeatable information and so may be used to predict where ECVs will be.

Communities
Plant communities are the traditional method of grouping vegetation. Although there are rules associated with naming plant communities there is often confusion associated with plant community names. This is often brought about by confusing naming systems, using abbreviations and the amount of work done in an area. Two of the most common systems will be outlined.

1. Structural
This system emphasises the vegetation structure, particularly the life-form and height of the tallest element. For example Forest indicates the dominance of tall trees, Open and Closed are used to indicate the canopy cover. Other grouping include Woodlands, Shrublands, Scrubs, Heathlands, Grasslands and Sedgelands.
This system was used extensively in the past to describe broad groupings. If used today it is usually modified to include a descriptor of the environment e.g. Sand Heathland, Swamp Scrub, Coastal Grassy forest.

2. Floristic
This system uses the plant name of the dominant species (sometimes 2 or 3 names are includes where there are co-dominant species) in addition to the structural name. Used mostly for working in small or very specific areas.
Example include:
Heath Tea-tree (Leptospermum myrsinoides) Heath
Scrub Sheoke (Allocasuarina paludosa) Heath
Coast Manna-gum (Eucalyptus pryoriana) Heathy Woodland
Messmate-Stringybark (Eucalyptus obliqua) - Narrow-leaf Peppermint (E. radiata) Sclerophyll Forest