Pollia
Pollia crispata is a ground cover that is related to the introduced weed trad, Tradescantia fluminensis. In fact, it rather looks like a giant form of trad. However, despite its robust appearance and ability to thrive in damp, moist and shady habitats, it is rather local, and absent from many apparently suitable habitats. A possible reason is that cattle used to be released into such areas in times of drought. They graze on it, as do wallabies and, possibly, wombats.
Pollia is the largest of the four native relatives of the serious introduced weed trad (Tradescantia fluminensis).
Pollia crispata colonises shaded sites but, like its relatives, dies out in deep shade. It has white flowers that don't seem to set seed on our site, perhaps because our plants are single clone and many members of this family are not self-fertile.
Pollia crispata spreads by growing horizontal shoots that produce roots at every node. In this way, a single plant can colonise a large area. This results in thousands of plants that are genetically a single clone, that is, a group of genetically identical individuals.
Like its weedy relative trad, Pollia crispata is self-incompatible, that is, it does not set seed with its own pollen. This presumably explains why no seedlings are found in many places where a carpet of adult plants grow. However, occasionally a clonal population expands to meet a different clonal population. Then, the plants pollinate each other, set seed, and produce seedlings like the ones shown below.
Producing seed in this way is important for two main reasons - seed can last over droughts and fire that might destroy the parent plants, and the resulting seedlings have a varying genetic makeup,
