At each point, we recorded the hydrology/substrate (flowing water, standing water, saturated mud, firm mud, dry wetland), water depth and dominant vegetation using nine broad vegetation groups: cattails (Typhaceae), cutgrass (Leersia oryzoides), forbs, hardstem bulrush (Scirpus acutus), Himalayan blackberry (Rubus discolor), other grasses (Poaceae), other sedges (Cyperaceae), rushes (Juncaceae) and willows (Salix spp.
The nine most-common plant species found in 20 PEM1 wetlands in the northern Sierra foothills were (not in order of prevalence) (A) common rush, (B) water smartweed, (C) sand spikerush, (D) rice cutgrass, (E) Baltic rush, (F) dallis grass, (G) common spikerush, (H) cattail and (I) willowherb.
Four species, including dallis grass (Paspalum dilatatum), common spikerush (Eleocharis macrostachya), willowherb (Epilobium ciliatum) and rice cutgrass (Leersia oryzoides) each occurred at between 5% and 10% of the points sampled, while all other species occurred at less than 5% of the points sampled.
Based on the random-point data collected from 184 PEM1 wetlands in 2008, the percent coverage by broad vegetation classes was, on average, 26% grasses (excluding rice cutgrass), 24% rushes, 12% cattails, 12% sedges (excluding hardstem bulrush), 7% Himalayan blackberry, 6% forbs, 5% hardstem bulrush, 3% willows and 1% rice cutgrass.
Most were obtained from an onsite nursery, but three species (pickerelweed, Pontederia cordata; softstem bulrush, Scirpus validus; and giant cutgrass, Zizaniopois miliacea) were imported from a Florida nursery (Duckworth-Cole, Inc.
Giant cutgrass dominates the perimeter shores of the open-water cell where bluefin killifish were collected, and the species may have been introduced into the wetland as eggs attached to plants imported from Florida.