15 October 2009

Lobe-fruited Mallee - Eucalyptus preissiana subsp. lobata

Click image to enlarge

Lobe-fruited Mallee - Eucalyptus preissiana subsp. lobata

Described in 1995, this subspecies occurs in a handful of locations to the west of Esperance, with the main one 55km or 34 miles away at Quagi Beach. Here it is very common and grows as impenetrable thickets over several hectares on shallow white sand over limestone. Mostly the multi-trunk (mallee) shrub-like eucalypts are around 1.5 metres (5') in height, but in hollows or sheltered from strong coastal winds can growth to twice that height.

Eucalyptus preissiana subsp. preissiana also grows in the region, but has smaller flowers and the shape of the fruit (seed pod) is radically different, with subspecies lobata having large protruding lobes, whereas subspecies preissiana has much smaller ones that are sunken within an inward sloping disc. Usually these subspecies do not grow together, although a little inland on acid soils towards Salvation Harbour, there is a colony of subspecies preissiana with a handful of subspecies lobata on the western end.

The large greenish yellow flowers (5 cm or 2" diameter) are quite spectacular and mass towards the outer branches. Depending on the reliability of seasonal rainfall they can bloom from August to November, with odd flowers blooming at other times too. The above photographs were taken during the latter part of September.

Eucalyptus preissiana subsp. lobata has a Priority Four - Rare Taxa rating, which means although it is rare, it is not threatened by any identifiable factors.