When the sudden appearance of an endangered flower halted a controversial housing project in the heart of California's wine country, the developer, Scott Schellinger, suspected he was the victim of a set-up.

Now, after calling in experts from the state's fish and game commission, who have backed his findings, he is claiming that the "discovery" of rare and protected Sebastopol meadowfoam on the eight-hectare site near San Francisco was the work of opponents who transplanted the flowers from elsewhere.

"It looked like a bad toupee," said one botanist, who observed the small, white flowers - latin name Limnanthes vinculans - growing through clods of "alien" soil.