Dryandra is a genus of 135 species in the Protea family (Proteaceae) and all occur naturally only in south-western Australia. The genus was created by the botanist Robert Brown based on specimens collected by him at King George Sound in December 1801 and was named in honour of Jonas Dryander, a botanist and librarian. For many years there has been confusion in the taxonomy of Dryandra with many species having no scientific name and others being known by incorrect names. This situation was resolved in 1996 when the genus was revised by Alex George. More recently, The Dryandra Book (2006) has documented all of George's species as well as additional species described since.

Characteristics

Within the Proteaceae, Dryandra is most closely related to Banksia although the latter genus has a wider distribution and is found in all Australian States and Territories. The relationship is so close that some botanists believe that the two genera should be combined. This view appears to be gaining wider acceptance and it is possible that Dryandra will be subsumed into Banksia in the future (see box). The Western Australian herbarium has adopted the new classification (2008).

Irrespective of the final outcome of the botanical classification of Banksia and Dryandra, the latter form a distinctive group horticulturally and no doubt will still be commonly referred to as "dryandras".

Like Banksia, the individual flowers of Dryandra are quite small and occur in dense clusters which can number several hundred individuals. The flowers are arranged in cone-shaped clusters, a feature which differs from the majority of banksias which have the flowers arranged around a vertical axis, giving the familiar cylindrical inflorescence (Banksia subgenus Banksia). The flower spike of Dryandra is superficially similar to the three Banksia species in the sub-genus Isostylis which would not be recognised as banksias by most people. These three species may be an evolutionary link between the two genera.

The flower heads are also surrounded by overlapping, scale-like bracts which often form a conspicuous part of the inflorescence. These bracts are absent in Banksia.

The bracts surrounding the flower heads of Dryandra species may be a conspicuous part of the inflorescence (left - Dryandra ferruginea) or confined to the base of the inflorescence (right - Dryandra formosa) Photos: Margaret Pieroni, Jan Hopgood

The flower clusters of most Dryandra species are cream, yellow, brown or orange in colour. There are one or two species where the inflorescence can have a pink colour in certain forms (eg. D.praemorsa, D.fraseri).

The flowers are followed by more or less woody follicles each containing one or two seeds. Unlike Banksia, where the follicles develop on large cones, the follicles in Dryandra are hidden within the spent flower clusters. In the majority of species these follicles remain tightly closed unless stimulated to open by heat, such as following a bushfire, or on the death of the plant. With a few species, the seed is released annually. The seeds themselves have papery wings which allows them to be distributed by wind.

Most dryandras are small to medium shrubs but there are many which are prostrate with underground stems. At least one species (D.arborea) is of tree proportions. A number of species have a "lignotuber", a woody swelling at or below ground level from which regeneration of the plant can occur if the above ground stems are destroyed.