Isoetes (bolanderi, echinospora, howellii, nuttallii, occidentalis) Provisional Herbaceous Alliance
- Primary Life FormHerb
- Elevation0-1500 m
- State RarityS3?
- Global RarityG3
- DistributionCAN: BC. USA: CA, OR, WA (NatureServe)
- Endemic to CaliforniaNo
- Endemic to California Floristic Province and DesertsNo
- Date Added1995/11/01
Isoetes bolanderi, Isoetes echinospora, Isoetes howellii, Isoetes nuttallii or Isoetes occidentalis is dominant or co-dominant in the herbaceous layer with Torreyochloa erecta.
Herbs < 25 cm; cover is open to continuous.
Submerged beds at permanently flooded and seasonally flooded margins of lakes, ponds, and streams. The USFWS Wetland Inventory (1996 national list) recognizes all Isoetes species as OBL plants.
Other Habitat, Alliance, and Community Groupings
|MCV (1995)||Quillwort series|
|NVCS (2009)||Isoetes (bolanderi, tenella, occidentalis, nuttallii) permanently flooded herbaceous alliance|
|Calveg||Wet grasses and forbs, Water|
|Holland||Coastal and valley freshwater marsh, Transmontane freshwater marsh, Montane freshwater marsh, Vernal marsh|
|WHR||Fresh emergent wetland|
|CDFW CA Code||52.109.00|
Isoetes plants arise from bulb-like bases developing grasslike, hollow leaves that taper to a pointed tip. Plants are perennials with evergreen or deciduous leaves. Quillworts reproduce by spores in the leaf bases. Identification to species level requires mature, dry female spores found in the decaying leaf bases or the soil (Hickman 1993, Taylor et al. 1993).
The alliance is a commonly seen but little sampled type; it occurs in mountain lakes and flooded ponds throughout cismontane California. Three stands at Harvey Monroe Hall RNA (Taylor 1984, see Cheng 2004) in the Sierra Nevada (M261E) include a bed of Isoetes occidentalis and another of I. occidentalis with Torreyochloa erecta. Other observed beds of I. occidentalis occur in shallow lakes in the Klamath Mountains (M261A), and beds of I. howellii are dominant in long-saturated parts of vernal pools of the Great Valley (262A). We need additional sampling and analysis to characterize better this apparently widespread alliance.
- Mason, H.L. 1957
- Taylor, W.C.;Luebke, N.T.;Britton, D.M.;Hickey, R.J.;Brunton, D.F. 1993