This document addresses the biology of Trifolium repens L. (referred to as white clover) with particular reference to the Australian environment, cultivation and use. Information included relates to the taxonomy and origin of white clover, general descriptions of its morphology, reproductive biology, biochemistry, and biotic and abiotic interactions. This document also addresses the potential for white clover to transfer genes via pollen and seed movement and for weediness. It should be noted that due to the large number of white clover cultivars as well as the highly heterozygous nature of white clover populations which results in many genotypes, it has been necessary to generalise much of the information provided in this document, and exceptions may be common. The purpose of this document is to provide baseline information about the parent organism for use in risk assessments of genetically modified (GM) Trifolium repens L. that may be released into the Australian environment.