29 November 2012

Agrostocrinum scabrum subsp. scabrum – False Blind Grass

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Agrostocrinum scabrum subsp. scabrum – False Blind Grass

This tufted perennial is commonly confused with Blind Grass (Stypandra glauca), as they both have a similar tussock-like appearance, blue flowers and in WA their distribution overlaps. However if you know what to look for, they are easy to tell apart. The WA endemic Agrostocrinum scabrum subsp. scabrum have only partially grasping leaf bases, whereas with Stypandra glauca they encircle the stem.

The blue flowers also differ especially the anthers and filaments (anther stem), with the (False Blind Grass) having thick, bent, white filaments and brown to black anthers. The other plant (Blind Grass, Stypandra glauca) has thin yellow filaments and thick yellow anthers. Other less obvious differences exist, but despite S. glauca being highly variable over its several State distribution, those mentioned above are reasonably consistent.

There are two Agrostocrinum scabrum subspecies, the other Agrostocrinum scabrum subsp. littorale is coastal and only occurs further west around Albany; it is a short spreading rhizomatous plant to 15 cm (6”) in height. Whereas the tufted Agrostocrinum scabrum subsp. scabrum can grow to 1.5 metres (5’) in height, although locally is usually around half that size.

Agrostocrinum scabrum subsp. scabrum occurs from NE of Perth to the western edge of the Nullarbor, plus most of the South West; it grows in a variety of non-calcareous soils, particularly in winter-wet locations and seepage areas. The bright blue flowers are around 2.5 cm (1”) diameter and depending on rainfall, will flower between September and December, although locally due to less rain and slightly warmer conditions are mostly finished by the end of November.

In WA the Agrostocrinum genus is placed in the Hemerocallidaceae family along with Caesia and Stypandra, but maybe listed elsewhere when other classification systems are used.