Banksia spinulosa
The hairpin banksia ("Banksia spinulosa") is a species of woody shrub, of the genus "Banksia" in the family Proteaceae, native to eastern Australia. Widely distributed, it is found as an understorey plant in open dry forest or heathland from Victoria to northern Queensland, generally on sandstone though sometimes also clay soils. It generally grows as a small shrub to in height, though can be a straggly tree to . It has long narrow leaves with inflorescences which can vary considerably in coloration; while the spikes are gold or less commonly yellowish, the emergent styles may be a wide range of colours – from black, purple, red, orange or yellow.
Banksia menziesii
Along with "Banksia attenuata", "Banksia menziesii" is a facultative phreatophyte. The two species are less strictly tied to the water table and hence able to grow in a wider variety of places within banksia woodland habitat around Perth than the co-occurring "Banksia ilicifolia" and "Banksia littoralis". Recent falls of the water table on the Swan Coastal Plain from use of the Gnangara Mound aquifer for Perth's water supply as well as years of below average rainfall have caused a drop in the population and vigour of "Banksia menziesii" since the mid-1960s. A 2009 Spanish study showed "Banksia menziesii" seedlings to be moderately sensitive to salinity. It is also sensitive to sulfur dioxide. A 1994 study by Byron Lamont and colleagues from Curtin University found that "Banksia menziesii" plants within of road verges had crowns two and a half times bigger, and set three times as many seeds as plants further away from the road, and that this was likely due to increased availability of nutrients and water from runoff.