Wilkesia hobdyi
Introduction '''''Wilkesia hobdyi''''', the '''dwarf iliau''', is a species of flowering plant in the family Asteraceae that is endemic to the island of Kauai in Hawaii. It was first collected in 1968, and was not formally described until 1971.The number of living plants is estimated at fewer than 300.It is considered Critically Imperiled in global rank which means it is at very high risk of extinction. It has been a federally protected species since 1992.The genus ''Wilkesia'' is one of three genera constituting the silversword alliance, a group of highly diverse yet genetically exceedingly closely related species, all thought to be descended from a colonizing ancestor related to the tarweed of North America.
Description ''Wilkesia hobdyi'' is a perennial shrub with branches reaching a length of  extending vertically from the base. Branch tips yield whorl, rather than spirals, of narrow, flat, grass-like, somewhat thick leaves around  long. Cream-colored flowers are produced in inflorescences  in diameter. Flowering has been observed most often in the winter months, butalso during June. This species is probably pollinated through outcrossing and is probably self-incompatible. Insects are the most likely pollinators. ''Wilkesia'' die after flowering.
Habitat ''Wilkesia hobdyi'' inhabits dry, nearly vertical rock outcroppings in the western part of the island at elevations of . Rainfall in these sites is less than 1,200 ml per year.Terrain typical of W. hobdyi habitat, western Kauai
Threats The primary threat to the species is grazing by feral goats. Native species evolved in the absence of grazing animals and thus did not develop any mechanism for protection. When goats were introduced in the 18th century, many native species were devastated. The existing plants are found only on nearly vertical cliffs which even goats cannot climb. The species is also threatened by encroachment by alien plant species, especially grasses which can smother the plants. Alien grasses also pose fire hazards which endanger the plants. The other species making up the ''Wilkesia'' genus, ''W. gymnoxiphium'', is not officially endangered, though it is also found only on Kaua'i and is not common there.
Associated plants Associated plants include ''āhinahina'' (''Artemisia'' spp.) ''iliau'' (''Wilkesia gymnoxiphium''), ''nehe'' (''Lipochaeta connata''), ''Lobelia niihauensis'', ''makou'' (''Peucedanum sandwicense''), ''kokio ula'' (''Hibiscus kokio''), ''alahee'' (''Psydrax odorata''), ''alaala wai nui'' (''Peperomia'' spp. ), naio (''Myoporum sandwicense''), ''ilima'' (''Sida fallax''), ''uhaloa'' (''Waltheria indica''), ''aalii'' (''Dodonaea viscosa''), and ''kāwelu'' (''Eragrostis variabilis'').
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