There are two types of marsh lands in San Diego County; freshwater marsh and coastal salt marsh. Both of these communities are very important for wildlife, and both have had extensive reductions due to channelization, dredging and vegetation removal.
Coastal Salt Marsh
Coastal salt marsh is found within the tidal zone on the edge of lagoons and bays. The major locations of this community are the Tijuana Estuary, Penasquitos Lagoon and the mouth of the Santa Margarita River. Dominant plants in coastal salt marsh are glasswort (Salicornia spp.), alkali heath (Frankenia salina), salt grass (Distichlis spicata) and cordgrass (Spartina foliosa).
Freshwater marsh land is found along stream courses and near riparian wetland areas. It is found near natural springs and ponded areas within the major stream channels. However, it has been affected by channelization and clearing of vegetation within stream channels. Freshwater marsh is found in small isolated areas along the major stream courses: San Diego, San Dieguito, San Luis Rey, and Santa Margarita as well as the upper ends of the major lagoons. Dominant plants within freshwater marsh include rushes (Juncus spp.), cattails (Typha angustifolia), bulrushes (or tules) (Scirpus spp.) and several species of small willows (Salix spp.).
Although marsh lands may not be as directly susceptible to fire as other types of vegetation due to the wetter conditions, they may suffer the indirect impacts of sedimentation and reduced water quality that occurs in areas burned upstream or upland. Loss of vegetation in upland or upstream areas can cause erosion and nutrient leaching that ultimately ends up in marsh lands.