Friday, December 21, 2012

Kusamaki: the Arhat Pine

Species name: Podocarpus macrophyllus

Common name: Buddhist pine

Location: UWO Greenhouse

Podocarps are native to a region from China all the way south to the northern tip of Australia. This particular species is native to a small region in China and Japan, but is incredibly abundant there even now. Since the name "Buddhist Pine" is incredibly misleading (this plant is not a pine!), the traditional Japanese name is being favoured by English-speaking countries as the new common name of this plant: Kusamaki. In nature this tree can reach up to 20 meters in height, but in a greenhouse it rarely reaches more than a couple meters.

When mature, the Kusamaki produces berry-like structures that are used to disperse seeds, much like the yew (which you can read about HERE and HERE). They are toxic to humans (definitely won't kill you, but certainly will make you regret your decision to consume them), but quite delicious to birds who eat the fleshy coating of the seeds and disperse the seeds themselves in their poo. This phenomenon a very common bird-plant relationship, with many species of plants actually requiring their seeds to pass through a bird's digestive tract in order to germinate. While in the bird's gizzard, the sand that they consume to help grind their food to a paste also lightly scours the seed coat, which allows  it to pop open once exposed once again to sunlight, organic material and water. This is called ornithochory (ornitho- for "bird" and -chory for "to spread/disperse").

The Japanese rely very heavily on this plant as a building material, as many traditional Japanese houses are still made out of wood and must be resistant to rain and strong against wind. The wood of this plant is very rot resistant, and has its own waterproofing. The other desirable characteristic about this plant is that it is very resistant to termites, a huge problem for some prefectures or states in Japan. In Hong Kong, the Kusamaki is regarded as one of the most prized trees for feng shui, which means it is very valuable for sale and trade. In some areas in Hong Kong, the tree has been hunted to near extirpation due to the high market value for mature specimens.