Echidnas and Honeysuckle
When we compare plants and animals, it can appear that plants are stationary, passively soaking up the sunlight, in comparison to the way animals move and actively seek food and shelter.
Echidnas and their scratchings can be seen alongside most tracks in the Reserve. This one was moving agilely along the logs, fixated to the point it seemed happy to get on with feeding if you just stood still.
Plants are amazingly competitive, though.
You can smell the flowering honeysuckle, an introduced species, for example. It grows to quickly fill the space and to move towards the light which is why it is described as invasive – it takes up space, crowding out the competition. It also entices pollinators with its scent and a nectar reward.
The following plants are also active in the competition for pollinators, to ensure they can reproduce and spread, moving towards more ground.
Grass Trigger plant, Stylidium graminifolium
This plant is quite tall among the grass and can be seen almost everywhere in the Reserve this Spring. It has pink flowers arranged in a raceme, and a rosette of long narrow leaves at the base.
When an insect visits the Stylidium graminifolium, a column resting against one of the petals of the flower is triggered upwards and pollen adheres to the insect. When it visits another flower, the pollen is then transferred when that trigger activates.
This strategy ensure pollination is successful – a combination of nectar reward and pollen transfer.
Purple beard- orchid, Calochilus robertsonii
The Calochilus robertsonii flowers from September to January (although, that seems too broad for the ones in the Reserve), responding to the heat by opening widely during the day. Unlike its relatives, the sun-orchids, it doesn’t close completely in cooler conditions or at night.
The beard-orchid produces a scent – like the bird-orchids – that attracts a male wasp. The wasp thinks the labellum is a female and in the attempt to mate, he collects pollen. He then passes this on to the next orchid.
In this case, the plant uses the strategy of pollination by deception. The plant also self-pollinates, another strategy of survival.
Tall sun-orchid, Thelymitra media
Like the beard-orchids, the Thelymitra media attracts a pollinator but doesn’t provide a reward.
The sun-orchid’s colouring, appearance and pseudo-pollen attracts pollen- gathering bees and flies. The orchid’s pollonia is transferred by the insect to other orchids.
This sun-orchid flowers at the same time as lilies and flags, in the Reserve, which do provide a pollination reward for visiting insects. It also seems to remain open for a longer time than some of its relatives (such as T.paucifolia), which would also increase the chances of cross- pollination.
Flowering in the Reserve, at present, this orchid can be found in the south western section.
The Gastrodia sesamoides attracts native bees through scent and by providing a starchy pseudo-pollen reward for the insect’s pollen- collecting activity.
The other survival strategy this plant uses is to draw on fungus –saprotrophic – to provide a source of nutrients, since it does not photosynthesise, itself.
References and further resources
Bishop, T. (2000) Field guide to the orchids of New South Wales and Victoria. UNSW Press: Sydney
Dearnaley, J. D.W. & Bougoure, J.J. (2010) Isotopic and molecular evidence for saprotrophic Marasmiaceae mycobionts in rhizomes of Gastrodia sesamoides. Fungal Ecology, 3, 288-294.
Jeanes, J. & Backhouse, G. (2006) Wild orchids of Victoria Australia. Aquatic Photographics: Seaford.
Mayfield, E. (2010) Flora of the Otway Plain and Ranges 1. CSIRO Publishing; Collingwood.
Mayfield, E. (2013) Flora of the Otway Plain and Ranges 2. CSIRO Publishing; Collingwood.