Mycorrhizae in a California serpentine grassland community

The grassland community on serpentine soil was found to have vesicular–arbuscular mycorrhizae. Twenty-seven species made up the herbaceous cover; 23 were annuals. Two annual species were from nonmycorrhizal families, but one had some colonization. Twenty-five species had colonization in over half the length of the roots. Annuals had especially heavy colonization, which frequently filled the cortex of the root. Of the herbaceous cover in the community 98% was mycorrhizal; 97% was colonized in over half the length of the roots; and 91% was colonized in over three-fourths the length of the roots. The common fungal symbionts were Glomus fasciculatum and Glomus tenue.