Dillwynia trichopoda

A prostrate to spreading shrub to 1 metre tall, to less than 1 metre wide, with stems with small hairs.

It occurs naturally in NSW and Qld; growing on the coast of NSW as far south as the Clyde River (Batemans Bay), extending north through the central coast subdivision, to as far west as Lithgow and Kandos, then extending north mainly along the coast to south-east of Gympie in Queensland. There are also some disjunct records inland from Bundaberg.

It grows in dry forest and woodland, sometimes on coastal headlands, on shallow sandstone soils.

Dillwynia is a member of the “pea” family. This generally means that leaves are alternate with stipules at the base of the petioles. Dillwynia have simple and alternate leaves, with stipules present and minute, or absent.

Leaves can be flat, terete or triangular in cross-section and often twisted.

In this species, leaves are to 5 mm long, and about 1 mm wide, spirally twisted, with the tips curved and pointed, smooth to warty with hairs coming out of the tubercules (warts), or hairless, mid to dark green in colour.

Flowers are, of course, pea-shaped (a term sometimes used is papilionate), with 5 petals in a fixed arrangement; the main back petal is called the “standard”, two lateral petals called “wings” and two fused petals at the bottom called the “keel” (in which the anthers and one carpel tend to be hidden).

In Dillwynia, flowers are yellow, or red and yellow (or orange/yellow) and are usually arranged singly or in small groups in leaf axils or on the ends of branchlets. The upper two of five sepal lobes are joined in a single “lip”. The standard petal is typically wider than high (a useful identification feature), and the keel is the same length as the wings. There are very small leafy bracts present on the common peduncle (which can fall early or be persistent) and bracteoles on flower pedicels (below the calyx).

In this species, flowers are borne singularly or up to clusters of 6 in terminal umbels, orange-yellow to yellow in colour, with the standard to 6 mm long and with striking red markings. The keel may also be red.

The fruit of all peas is a pod. In this species, they are approximately 5 mm long with a reticulate pattern on the seeds.