The left-behind tree

Pyrenaria spectabilis (common tutcheria) is a rare local species that is now legally protected. It is dispersed by ‘scatter-hoarding’ rodents that collect and store fruits to eat later. The seeds often germinate when the rodent fails to retrieve the fruit.

The bad news: these rodents no longer survive in Hong Kong and, as a consequence, tree species with this dispersal mechanism are rare and noticeably absent from secondary forests. This is in striking contrast with the closely related species, Polyspora axillaris, which produces winged seeds that hitch a ride on passing breezes. As a result, Polyspora axillaris is far more common in Hong Kong, and is regarded as a pioneer species that is able to colonise disturbed areas and often dominates early-stage secondary forests.

Hero image: Sally Grace Bunker