spikeweed noun1 •Any of several annual herbaceous plants native to California, belonging to the genus Centromadia (family Asteraceae), characterized by spiny involucral bracts and typically found in seasonally dry or disturbed habitats.The northern plain was formerly dominated by Casuarina trees and a carpet of Spikeweed. Once the Spikeweed had been removed, a ground cover of indigenous Little sticky seed soon developed. — 2010 formsspikeweeds
