Lygodium japonicum (SCHIZAEACEAE) Japanese Climbing Fern, Kani-kusa, Tsuru-shinobu

Weeds to Whack

Lygodium japonicum has been observed at Walton Bridge Reserve The Gap, directly under the bridge, growing on and amongst Native Ginger. There is a local native Lygodium microphyllum Climbing Snake Fern in rainforest, swamp forest or open forest; not common, north from Iluka, NSW. “Lygodium japonicum is a vine-like fern with a highly developed ability to climb herbs, shurbs, and trees. Its invasiveness arises from its ability climb to heights of 30 m and smothers all vegetation by forming dense mats, which displace native species, alters fire ecology, and impacts rare, threatened, and endangered species,” according to the Global Invasive Species Database. Known [as native in Australia] only from Darwin, Northern Territory; probably a garden escape. Reported from Osbourne Island, northern WA but these specimens are a form of L. flexuosum. Introduced in Queensland and NSW. PlantNet on this species: Rachis sparsely pubescent, subterete, flattened on 1 side with ridged edges; primary rachis branches c. 2 mm long; secondary pinnae broadly lanceolate-triangular, 10-17 cm long, 7-17 cm wide, often broader than long, 3-pinnate; pinnule stalks reducing in length towards pinna apex; basal tertiary pinnules 3-8 cm long, 2.5-8 cm wide; ultimate pinnules ovate, lanceolate to triangular; sterile ones fused, palmately-lobed; terminal lobe much longer, membranous, sparsely pubescent; base + hastate; margins entire or crenulate; veins free; sporogenous pinnules smaller and more finely dissected than sterile ones. Sporogenous lobes 1-5 mm long.

Photo: Robert Whyte