Restoring native grasses is key to reestablishing healthy ecosystems, and land managers need species-specific information to determine whether or not to incorporate mycorrhizae into restoration plans. This thesis provides specific information regarding the effects of mycorrhizae collected from a California coastal prairie on two native perennial grasses, California brome (Bromus carinatus) and purple needle grass ( Nassella pulchra), and one non-native annual grass, soft chess ( Bromus hordeaceus).

Competition experiments were set up between seedlings growing in the presence or absence of mycorrhizal inoculum in native soils under relatively controlled conditions within a greenhouse. Mycorrhizal inoculation caused greater and faster seedling emergence in all three grasses. Only Nassella pulchra demonstrated a significant positive growth response to inoculation, which persisted when in competition with and at the expense of Bromus hordeaceus. Inoculated Bromus hordeaceus plants, however, produced significantly more seed and more viable seed when grown alone and in competition.