Botany Photo of the Day

Two folks from British Columbia contributed today's images, both submitted via BPotD Flickr Group Pool. Lotus J., aka ngawangchodron@Flickr submitted the first image (original image) and Brettf@Flickr submitted the second (original image). Thank you to both of you, much appreciated.

Both photographs demonstrate a member of the genus Cladonia, or cup lichens. One of the distinguishing features of Cladonia is a two-part body consisting of primary thalli and podetia. Primary thalli and podetia are present in both images; the thalli are the “flat little crusty green bits” (most of what can be seen in the first photograph, but not as ubiquitous in the second) while the podetia are the stalked structures. The red parts on the end of some of the podetia are apothecia, a particular type of spore-bearing structure.

Identification of Cladonia can be difficult, and I haven't spent a lot of time attempting to identify the one in the second photograph, though it should be possible with the podetia present. Identifying Cladonia before the podetia are developed, however, is difficult beyond recognizing that it is a Cladonia. As Trevor Goward writes in Plants of Coastal British Columbia: “Though easy to recognize as a group, the cladonia scales are notoriously difficult to identify to species. Still, it can be ‘fun’ trying (consult a technical manual such as Thomson 1967).”

Photography resource link: Photography Locations via The Luminous Landscape. Finding where to photograph can be difficult (especially when travelling), so resources like these are very helpful. I only wish such a thing existed for wildflowers, since this resource concentrates on landscapes.