what is the opposite of contractile?

Jane McGary janemcgary@earthlink.net
Wed, 19 Sep 2007 10:54:28 PDT
Max asked about Drimia maritima and its tendency to rise to the surface.

Possibly bulbs that "push" themselves out of the soil evolved in situations 
of highly mobile soils, such as dunes or repeatedly flooded zones, and this 
strategy keeps the bulb at an optimal level where it will not be buried too 
deeply and have to expend too much stored energy extending its leaves and 
scape to the increasingly distant surface.

This would apply to Drimia maritima in one of its habitats, coastal dunes, 
but it also grows in rocky situations that appear quite stable. Because 
sheep and goats don't eat it, it probably has spread into habitats that 
would have been occupied by other plants before human activity changed the 

Other geophytes found in very mobile situations, such as riverbanks and 
scree, often reproduce vegetatively by stolons or very elongated bulbs 
(e.g., certain riparian Lilium species).

Jane McGary
Northwestern Oregon, USA

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