Devils Bridge, North Otago.

Devils Bridge is a limestone ridge just inland from Oamaru. It is undercut by a stream. The stream has been damned creating a large reservoir on the northern side which is surrounded by a planted area that has been covenanted. A few old broadleaf (Griselinia littoralis) trees exist within coarse talus rolled off a second connecting limestone ridge and some outcrop with a rock art site is also present. Swamp nettle (Urtica perconfusa) occurs around the waterline. On the southern side, the stream emerges into a gully enclosing a fragment of natural forest that contains a stand of large, old kowhais (Sophora microphylla) together with cabbage tree (Cordyline australis) and broadleaf (Griselinia littoralis). The understorey vegetation consists of various ferns and herbaceous species that are tolerant of the underlying limestone substrate. Such forest remnants are very rare coastal North Otago as most of the land has been developed for agriculture. We plant to visit both these Covenants and possibly a third, in this geologically interesting landscape.

We will meet at the Botany Department carpark at 8.00 am and travel to Weston (just south of Oamaru) and then on to Devils Bridge. Bring lunch, warm clothing, rain gear and suitable footwear. Distance from Dunedin to Weston is approximately 120 km with a travel time of 1 and a half hours. Suggested carpool contribution $48. Contact David Lyttle (email djl1yttle@gmail.com Ph (03) 454 5470).