Recent genetic testing has confirmed the existence of three distinct forms, but as of 2005 these have no taxonomic status. Distribution and habitat Banksia brownii occurs between Albany (35°S) and the Stirling Range (34°24'S) in the southwest of Western Australia, at the juncture of the Esperance Plains, Warren and Jarrah Forest biogeographic regions. This is the taxonomically richest area for Banksia, with 19 species, of which six are endemic, including B. brownii itself. It is cool and wet, with temperatures between four and 30 °C (39–86 °F) and rainfall of around 800 millimetres (31 in). The species occurs there in two distinct population clusters: southern populations occur among low woodland of Eucalyptus marginata (jarrah) in shallow, nutrient-poor white or grey sand over laterite; Stirling Range populations occur at altitudes of between 500 and 1100 metres (1640–3960 ft), among heath on rocky mountain slopes and tops, and in shale in gullies. There are 27 known populations within this region, but only nine of these populations contain more than 10 individual plants, and only five populations have more than 100. Ten populations are now presumed extinct. The total number of plants is estimated at around 1000. Ecology Coastal plants begin to flower at around five years from seed, but plants in the Stirling Range take much longer to mature. In one Stirling Range population, only 15% of plants had flowered after eight years. Flowering time is highly variable, but in general it occurs between March and August, with a peak around June. More flowers open during the day than at night. As with other Banksia species, B. brownii is a heavy producer of nectar, and serves as a food source for a range of nectariferous birds, mammals and insects. Honeyeaters such as Phylidonyris novaehollandiae (New Holland honeyeater), Acanthorhynchus superciliosus (western spinebill) and Anthochaera carunculata (red wattlebird) are frequent visitors that often carry heavy pollen loads, making them important pollinators. Nocturnal mammals such as Rattus fuscipes (bush rat) and Tarsipes rostratus (honey possum) also carry heavy pollen loads, but the foraging behaviour of bush rats suggests that these may transfer pollen only over very short distances. Invertebrate visitors include the introduced Apis mellifera (western honeybee), native bees, flies and ants; bees appear to be effective pollinators, but ants and flies forage only at the base of flowers and do not come in contact with plant pollen. The species is partly self-compatible, as some