Blackboy Hill, was named after the Xanthorrhoea preissii, which dominated the site and is now absorbed into Greenmount, Western Australia.
Its occurrence is a characteristic of two other Marri (Corymbia calophylla) communities, but the Marri/Xanthorrhoea community is distinguished by the drier soils of the communities range along the eastern edge of the Swan Coastal Plain.
Xanthorrhoea | Xanthorrhoea preissii | ''Rhagodia preissii'' subsp. ''obovata'' | Xanthorrhoea australis | Callitris preissii |
The granite areas have two types one is an area covered by Xanthorrhoea preissii, Gastrolobium calycinum with a Borya herbfield and the other is dominated by Melaleuca, Dodonaea also with a herbfield of Borya.