Naturalized subterranean clover (Trifolium subterraneum L.) in Western Australia: the strains, their distributions, characteistics, and possible origins

Abstract

Seventy-two previously undescribed strains of subterranean clover were collected around Perth and in older Western Australian farming districts during 1960-1962. These are briefly described and their observed distributions listed. A few of them could have arisen in situ by natural crossing and mutation, but the majority appeared to have been introduced.

A study of their observed distributions, together with a consideration of historical factors, suggests that many of the strains were introduced as early as the 1830's or 1840's. Because this was before the opening of the Suez Canal, it seems likely that they originated in England, Portugal, Madeira, or the Canary Islands, rather than throughout the Mediterranean as has been previously suggested.

The commoner strains showed distinct patterns of colonization in one area, followed by varying amounts of spread along transport routes, probably by stock as undigested seeds. Indirect evidence suggested, however, that this mode of transport could not have accounted for the original transport of strains from the coast to inland areas, where many of them appear first to have become established. It is concluded that most of these must have been carried inland directly in imported hay or similar materials.