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Summary

Many restoration guidelines strongly recommend the use of local sources of seed in

native plant revegetation projects. These recommendations are based on assumptions

that the species used for revegetation are cross-pollinated and woody, and were

originally developed for overstorey vegetation in the northern hemisphere. We

challenge their validity with respect to replacing or enhancing the native Australian

grass component of degraded rangelands. Firstly, obligatory cross pollination has not

been recorded in any Australian native grasses except for a few dioecious species.

Indeed the majority of Australian native grasses so far studied have revealed

complicated breeding systems that provide flexibility allowing reproduction and

genotypes to be matched to the variable Australian environment. Secondly, we argue

that the genetic dissimilarity among populations of a species is not proportional to the

distance between them but is more related to the environmental stresses that have been

placed on those populations in the past. We therefore conclude that there is little

justification for the recommendation that only local sources of seed of Australian

native grasses should be used particularly for large-scale revegetation programs. We

provide some general guidelines for deciding on the seed sources to use depending on

the purpose of the revegetation and characteristics of the species of choice.