Eats Wood.

Star (Christchurch), Volume LXVI, Issue 20359, 17 July 1934, Page 6

Eats Wood.

Nature Notes.

By

James Drummond,

F.L.S., F.Z.S.

THREADED as a destroyer in harbours is a little crustacean, the gribble, Limnoria. It looks like a woodlouse, but is only one-eighth or one-sixth of an inch long. Its burrows in timber in the water arc about one-twentieth of an inch in diameter. To make its home, it gnaws wood and swallows it, and, probably, digests it. There is no record of any other food it takes. In Otago Harbour it is troublesome on floating harbour-plant made of New Zealand timbers, and in wharves. It demands attention in Lyttelton Harbour. Wellington wharves have to be protected against it. In Auckland it ranks as a very troublesome pest. Associated with it in Auckland Harbour is another wood-boring crustacean, Chelura terebrans. An allied species, Sphasroma terebrans, has been reported from New Zealand, Australia. Florida, Brazil, South Africa, India and Ceylon. Some timbers resist the gribble and the shipworm better than other timbers do. Dr W. T. Caiman, an expert on the staff of the British Museum, attributes the greater resistance of some timbers not to their hardness but to their essential oils or to their alkaloids. The best resisters on his list are the South American greenheart, the Australian jarrah, the Australian turpentine and the New Zealand totara. Dr Caiman does not express absolute faith in any protective measures tried. One difficulty is that sufficient young borers may get into the interior of timber through a very - small, unprotected space. Once in they begin to destroy. His conclusion is that the shipworm and the wood-boring crustaceans ere indifferent to the hardness of timbers. Resistance is only temporary. Every timber commercially available is attacked sooner or later. There is evidence that the shipworm riddled part of Drake's Golden Hind, which was planked with oak.