Part One covered hints for photographing orchids so as to be able to identify the plant. Part Two gives an example with Cyrtostylis robusta (Winter Gnat Orchid) and C. reniformis (Small Gnat Orchid).
Although the flowering times are different – C reniformis is spring flowering and C. robusta is winter flowering – there is a slight overlap in August when it is possible for both to be flowering at the same time and in the same place.
The flowers are very similar but major difference between the two species is the leaf. Both leaves are roughly kidney shape but C. robusta is pale green with pale , almost undistinguished veins, silvery underneath whilst C. reniformis is heavily veined, blue-green above and green below.
The other differences are more subtle.
C. reniformis has dark buds and the apex of the labellum tends to be rounded rather than pointed
C. robusta has pale reddish buds and larger flowers, labellum crenulated (slightly wavy) and a fine point at the apex.
Consequently, it is important that photographs of the flowers clearly show the labellum – pointed labellum apex for C. robusta compared with the rounded labellum tip of C. reniformis.
The following article is from the April 2016 Journal of the Native Orchid Society of South Australia. The article is complete in itself but Part Two of this post will illustrate how images can help with images of Crytostylis robusta and C. reniformis.
Orchids are beautiful plants and many of us like to capture that beauty on photographs. And there are many beautiful pictures around.
Many times NOSSA, the Herbarium and other specialist groups receive images requesting identification but the vital information is missing.
When photographing for identification, it is necessary to take more than one image, particularly if you are unable to easily return to the site for more images. When in doubt, take several shots from many different angles highlighting different features of the plant and its habitat.
Another very important point to remember is, when there are several of the same plant, to photograph the orchid that is most representative of the group, not the atypical or unusual plant.
As a general guide, it is helpful to take a picture of each of the following
individual flower – both from the front and the side, occasionally the back.
leaf or leaves
Other helpful things to consider photographing are:
capsules of the finished flower – sometimes it can yield useful information.
for some genera, the stem can also be a helpful feature as between some species there can be a difference in the hairiness of the stem.
It is also worth including in a photograph an indication of whether the plants are growing in colonies with others or as scattered individual plants.
Importance of Size
It is also good to give an idea of size, this can be as simple as using a thumb or hand, a coin (show the reverse not the head) or any item that had an easily recognized size. It is important to have the object next to the feature being photographed. For example, a coin on the ground next to a leaf or a hand immediately behind the flower gives a clear indication of size. Remember to take another photo without the hand or coin.
Some Specific Identifying Features
Some species are distinctive and easily recognised, eg the Flying Duck Orchid, but others are not and it is helpful to know what part of the plant to photograph as different genera will have different identifying features.
Spider orchids – the tips of the segments (petals and sepals) and details of the labellum are important
Sun orchids – the column in the middle, the ovary at the base of the flower, and the number of bracts (leaf-like growth) on the stems
Pink fingers – the length of the leaf in comparison with the length of the flower stalk; also the back of the flower is helpful
Gnat orchid – the leaf is the best identifying feature, but also the bud can be helpful
Hyacinth orchid (of the Adelaide Hills) – labellum
Mosquito, Mayfly and Helmet orchids when not in flower – both sides of the leaf
Gastrodia – the flower spike
Rufoushoods – side view of the flower and close up of the labellum as the hairs on or surrounding the labellum are important features.
Leek Orchids – the labellum is very important, as well as part if not all of the flower spike as the distance between the individual flowers aids identification
Greenhoods – if present, the non-flowering rosette of leaves
The Australian Virtual Herbarium has some good tips for photographing flower. Click here to visit the site
This image lacks the ends of the segments to determine the identification. The presence or absence of clubs on the ends of the segments (petals and sepals) can often be the distinguishing feature with many of the Arachnorchis (Spider Orchids).
These leaves are an unusual shape and by themselves are not suitable for identification