The Alaska Vegetation Classification - Alaska Geobotany Center ...

Successlonal status-In some cases, these communities extend into ponds,replacing aquatic or emergent (marsh) communities. In other cases, they occupy bogpools brought into existence by various bog processes. As the peat mat thickens,many herb bog meadow communities gradually will be replaced by sedge bog orsedge-moss bog communities.Closely related types-Herb bog meadows are similar to herb wet meadows butoccur on peat substrates and are usually dominated by different species (commonlyMenyanthes trifoliata). They also are similar to herb marshes but have a peat substrateand are never dominated by Equisetum fluviatile. Herb bog meadows aresimilar to sedge bog meadows and sedge-moss bog meadows but have few sedges.Photographs-Dachnowski-Stokes 1941, figure 10; Tande 1983, plate 23; figure 71,this publication.Primary references-Dachnowski-Stokes 1941, Griggs 1936, Racine 1978b, Ritchieand others 1981, Tande 1983.Communltles-Menyanthes trifoliata (Dachnowski-Stokes 1941, Griggs 1936,Palmer 1942, Ritchie and others 1981, Rosenberg 1986, Young and Racine 1976).Menyanthes trifoliatalSphagnum spp. (Racine 1978b, Scheierl and Meyer 1977,Seguin 1977). Menyanthes frifoliata-Ranunculus pallasii (Webber and others 1978).Menyanthes trif~/iata-Potentilla palusrris (Griggs 1936, Tande 1983). Hippurisvulgaris-Menyanthes trifoliata (Cooper 1942). Viola /angsdorffii/Sphagnumgirgensohnii-Rh~idiadel~hus friquetrus (Bank 1951).111.8.3.4. Halophytic Herb Wet MeadowDescrlptlon-These communities are dominated by halophytic herbs such asTriglochin maritimum, Plantago maritima, Honckenya peploides, Meltensia maritima,Atriplexspp., and Cochlearia officinalis (fig. 72). Scattered halophytic grasses(usually Puccinellia spp.) or sedges may be present. Woody plants, mosses, andlichens generally are absent. Scattered shrubs may be present in some sloughlevee halophylic herb communities, along with scattered representatives of otherless halophytic species such as Poa eminens, Festuca rubra, and flymus arenarius.Plant cover often is open. A relatively dense stand of Triglochin maritimum andPotentilla egediiin upper Cook Inlet had a peak standing crop of 412 k 63 grams persquare meter (3,675 f 560 Iblacre) (Vince and Snow 1984).Distribution and site characteristics-Halophytic herb communities occur throughoutthe State at the seaward edges of beaches and coastal marshes, on gentleswales and backslopes within coastal marshes, and on coastal slough levees. Thesubstrate consists of tidally deposited silts, sands, or pebbles and is inundated atleast a few times per month by high tides. As the tides recede, water runs rapidly offthe surface leaving it firm, but silt substrates remain saturated below the upper 1 or2 centimeters (0.5 to 1 in). Measured substrate salinity and pH range from 6 to 13parts per thousand and pH 6.4 to 8.6. respectively.Successional status-These are early successional communities; on progradingbeaches and marshes, most will be replaced gradually on marshes by halophyticsedge meadows (usually Carex lyngbyaei, C. subspathacea, or C. ramenski,) and onbeaches by Elymus arenarius communities.