Zieria involucrata

A narrow and erect shrub, growing to a height to 2 metres, with an overall green-grey appearance.

It has a very restricted distribution, growing in the north and west of Sydney, in areas such as Marramarra National Park near Maroota, Canoelands; Parr State Conservation Area north of Colo and west of St Albans and further north; then around Kurrajong, Springwood/Faulconbridge and north of Wentworth Falls.

It is typically found in dry and wet sclerophyll woodland and forest, on Hawkesbury sandstone and Narrabeen Group sandstone soils, as well as Quaternary alluvium in some cases, usually in gullies.

It is a listed threatened species in the wild.

The branches are covered in hairs which give a velvet-texture.

Zieria spp. have leaves arranged in opposite pairs, compound with three leaflets (tri-foliolate) or one leaflet (uni-foliolate). When tri-foliolate, the leaflets are often similar in shape with the middle leaflet often larger, and with leaves usually strongly odorous, green to grey-green.
In this species, the leaves can be a mixture of tri-foliolate and uni-foliolate leaves, in varying ratios (sometimes most leaves uni-foliolate), densely covered with hairs which form a soft, velvety covering (tomentum); to 55 mm long and to 15 mm wide; upper surface mid to dark-green, lower surface grey-green.

Zieria spp. have flowers arranged in groups (cymose clusters) in the leaf axils and have four sepals joined at the base and four petals, alternating with the sepals. There are four stamens and four fused carpels. In this species, the flower clusters consist of up to 25 flowers, with clusters shorter than the leaves, white with pink tinges, and slightly hairy, occurring from August to October. The flower clusters are surrounded by small bracts.

Zieria have a fruit described as a schizocarp-capsule which splits into segments called cocci (singular coccus). Fruit generally have four cocci, each containing one or two seeds. In this species, the cocci are hairy, lacking an oil body (elaisome).