Large Duck-orchid

Spring is hearing the first Oriole to arrive, catching a glimpse of a Monarch in a fern gully and coming across a stand of the Large Duck-orchid.

These unusual terrestrial orchids are native to the south-east of Australia and prefer heathy or open woodland. Although widespread throughout much of Victoria they are uncommon. In West and South Gippsland they are mostly found in coastal woodlands.

Found widely throughout Victoria in a variety of habitats

Duck-orchids can be hard to spot – they are quite tiny and their red-brown flowers often disappear into the background of leaf litter.

Duck-orchids attract insects such as sawflies which pollinate the plant through a process of pseudocopulation. The male sawfly sees the Duck-orchid as a female sawfly. The ‘head’ and ‘beak’ of the duck are the labellum of the flower and when an insect is attracted to enter the throat, the labellum snaps shut. The trapped insect struggles to escape and so deposits any pollen it might be carrying and picks up more from the plant. After a short while, the labellum ‘opens’ and the insect ‘escapes’ and flies to the next plant, so continuing the essential pollination process enabling fertilization and the production of seed. 

The closed labellum is obvious in the bottom flower

The evolution of such a process and the infrastructure to support it is astounding.

Duck-orchids are extremely difficult to propagate. Despite the availability of so-called duck-orchid seed from disreputable sources, the species requires a very specific symbiotic relationship with particular fungi species found principally in the soils of heathy-eucalypt woodlands.

The Large Duck-orchid, Caleana major was named in honour of George Caley, an early English botanist appointed by Sir Joseph Banks as a botanical collector in NSW in 1798.