From
the abstracts of the "Victorian Rainforest Symposium"
17-11-1991
A Concise Definition of Rainforest for Victoria
Rainforest is defined by a combination of ecological, floristic and structural attributes. In the event of ambiguity, ecological criteria are to be given precedence over floristic and structural criteria and floristic criteria are to be given precedence over structural criteria.
Rainforest is defined ecologically as fire-sensitive forest composed
of or dominated by primary or secondary rainforest species. Fire-sensitive
forest is defined as a forest which exhibits a combination of fireproof
site characteristics with fireresistant or fire-retardant vegetation
characteristics which minimize the risk of destruction of the rainforest
canopy by running crown Fire. The ecological definition includes transitional
(ecotonal) and seral (Secondary or mixed) communities once they have
developed a 
recognizable
understorey canopy of rainforest species below an overstorey of sclerophyll
emergents. Primary rainforest species are defined as shade-tolerant
species which are able to establish or perpetuate themselves (either
vegetatively or from seed), in the absence of fire, below an undisturbed
canopy, or in minor canopy gaps resulting from endogenous processes
of renewal within the rainforest ecosystem, such as isolated windthrow
or endemic forest pathology. Such species are not dependent on fire
for their regeneration. 
Rainforest is defined floristically as vegetation with a characteristic composition which is consistent with that of rainforest communities or sub-communities described on the basis of a complete regional or statewide floristic analysis of reliable quadrat data. Rainforest may be recognized in the field using floristic field keys based on differential species. Rainforest is defined structurally as forest vegetation with a rainforest canopy which provides the habitat for a characteristic diversity of dependent life forms. The rainforest canopy is defined as a more or less continuous closed canopy composed of primary and/or secondary species. Most primary rainforest species are broad-leaved and evergreen.
Photos of Merrimans Ck. in the Strzelecki Ranges.