Botany Photo of the Day

It's early March, so it's time for my mind to drift to thoughts of visiting California for wildflowers and gardens. This photograph is from my 2008 foray, when I visited the Arboretum at the University of California Santa Cruz.

The UCSC Arboretum is famed for its extensive southern hemisphere collections. Accordingly, this vine / climber is a species from Western Australia, Kennedia nigricans, variously known as black kennedia, black coral-pea, black-bean or snakevine. As Wikipedia notes, Kennedia nigricans is a "vigorous" plant used for covering embankments or structures (and this was the case at UCSC Arboretum, where it enveloped a trellis if I recall correctly). As noted by Rodger Elliot, though, in Australian Plants Online: Australian Climbing Plants: "...it is worth considering...using climbers by letting them wander through other plants. There are many Australian climbers which are not overly vigorous which are ideal for this purpose but you need to be selective. If you try this with Kennedia nigricans, K.retrorsa or K.rubicunda you'll find that not only will other plants in the garden be swamped but your fence may also be overcome and end up lying horizontal! I've seen K.nigricans kill a forest oak (Allocasuarina torulosa) just by smothering it." Given that individuals can reach at least 4m high and have a spread of 6m, it seems a species to be judiciously used in cultivated situations.

Nearly 80% of the world's antibiotics (including antibacterials and antifungals) are derived from soil-borne bacteria, primarily from the genus Streptomyces. However, it is also known that some streptomycetes can live within plants as endophytic bacteria. Not all plant species have endophytic streptomycetes, and the minority that do typically only have one or two species. In one survey of Kennedia nigricans, though, thirty-nine species were discovered: Scanning electron microscopy of some endophytic streptomycetes in snakevine - Kennedia nigricans (Castillo et. al., 2006, doi:10.1002/sca.4950270606). Of the thirty-nine, seven were found to have antibacterial or antifungal properties.