Wet meadows in the Southern Rocky Mountains are herbaceous wetlands with mineral soils and a fluctuating water table. These wetlands are found throughout both the Rocky Mountain and Intermountain regions, occurring at elevations from the montane to the alpine (2,130-3,960 m or 7,000-13,000 ft). Wet meadows occupy wet sites with low-velocity surface and subsurface flows, typically on flat areas or gentle slopes, but they also may be found on sub-irrigated sites with slopes up to 10%. In montane and subalpine valleys, these wetlands occur as large open meadows, at the base of toeslope seeps, and as narrow strips bordering ponds, lakes, and streams. In the alpine, these wetlands typically occupy small depressions located below late-melting snow patches or snowbeds. Dwarf shrublands, typically dominated by willow (Salix spp.), often occur adjacent to or ring these alpine depressional wetlands, reflecting a change in the snowmelt regime. Wet meadow soil are mineral, but may have a top layer of organic matter known as a histic epipedon. In either case, soils show typical hydric soil characteristics, including high organic content and/or low chroma and redoximorphic features. This system often occurs as a mosaic of several plant associations, and may be found adjacent to a variety of shrub communities. Wet meadows are often dominated by graminoids, although forb cover may be substantial in areas at higher elevations. Characteristic species at the highest elevations include mountain sedge (Carex scopulorum), sheep sedge (C. illota), hair-like sedge (C. capillaris), black alpine sedge (C. nigricans), Drummond's rush (Juncus drummondii), marsh marigold (Caltha leptosepala), and brook saxifrage (Saxifraga odontoloma). At subalpine to upper montane elevations, water sedge (Carex aquatilis), and beaked sedge (C. utriculata), either separately or in combination, form a broadly distributed characteristic community. Other common species of this zone include smallwing sedge (C. microptera), analogue sedge (C. simulata), tufted hairgrass (Deschampsia cespitosa), fewflower spikerush (Eleocharis quinqueflora), bluejoint reedgrass (Calamagrostis canadensis), heartleaf bittercress (Cardamine cordifolia), tall fringed bluebells (Mertensia ciliata), arrowleaf ragwort (Senecio triangularis), elephanthead lousewort (Pedicularis groenlandica), and large leaf avens (Geum macrophyllum). At mid to lower montane elevations, clustered field sedge (Carex praegracilis), Nebraska sedge (C. nebrascensis), woolly sedge (C. pellita), common spikerush (Eleocharis palustris), and mountain rush (Juncus balticus var. montanus) are typical dominants.

Hydrologic regime is a key factor defining wet meadows and distinguishing them from other wetland types. Wet meadows occur were the soil is seasonally saturated and may be seasonally flooded, but high water tables do not persist throughout the growing season. Water tables are typically high early in the growing season and draw down by the end of the season. Thus wet meadows lack the perennially high water tables and organic soils found in fens and the large seasonal and inter-annual water table fluctuations characteristic of marshes. Wet meadows can be found in riparian corridors and on floodplains and may be hydrologically connected to the stream. However, they lack the influence of high velocity surface flows, scouring, and sediment deposition that characterizes the active riparian zone.

Rocky Mountain Alpine-Montane Wet Meadow systems occur throughout the Rocky Mountains and Intermountain West regions, ranging in elevation from montane to alpine (1000-3600 m). Colorado occurrences are generally found in the mountainous central portion of the state, including the intermontane valleys.

Rocky Mountain Alpine-Montane Wet Meadow is a small patch system.

In Colorado, wet meadow systems are largely confined to the Southern Rocky Mountain and Intermountain regions, landscapes of generally high topographic relief shaped by glaciation, moving water, and mass wasting. These processes have strongly influenced the geomorphology of the landscape, providing the settings for wet meadow development. Sites occupied by wet meadows include large open meadows in high montane valleys; small openings in subalpine willow carrs or coniferous forests; saturated soils near lakes, low-order streams, and backwater areas of larger rivers; in and near running water of headwater streams, seeps, and springs; as narrow strips bordering ponds and streams at lower elevations; and small depressions located below late-melting alpine snow patches or snowbeds.

Wet meadow systems span a wide elevational range (7,000-13,000 feet) and occur in a wide variety of geomorphic settings, but always occupy wetter sites with very low-velocity surface and subsurface flows. Wet meadows have seasonally saturated conditions and most are supported, in part, by groundwater. Thus wet meadows are found in landscape settings where groundwater levels are near the soil surface. Water sources for wet meadows include surface water, groundwater, and direct precipitation, with the relative importance of each varying among individual wetlands. Generally, direct precipitation is the least important hydrologic input while groundwater is the most important contributor. The Rocky Mountain climate is continental and semi-arid with warm, with dry summers and cold winters. Average annual temperature ranges from 25o to 60o F, while average precipitation ranges from approximately 20 inches in the montane zone to 60 inches at higher elevations. Most precipitation occurs as snowfall during the winter months. The interaction of climate and geomorphology has a strong influence on local hydrological processes in wetlands. Snowmelt at high elevations contributes a large proportion of water to most wetland types through its influence on groundwater and surface water dynamics. Wet meadows are closely associated with snowmelt, which maintains a high water table, and are typically not subjected to high disturbance events such as flooding. In alpine tundra wet meadows, snowdepth and timing of melt are the most important determinants of vegetation patterns. Alternatively montane wet meadows may be seasonally flooded by overbank flooding or beaver activity.

Salinity and alkalinity are generally low due to the frequent flushing of moisture through meadows. Soils typically possess a high proportion of organic matter, but this may vary considerably depending on the frequency and magnitude of alluvial deposition and water table depth. Organic composition of the soil often includes a thin layer near the soil surface. Because high water tables do not persist throughout the growing season, organic matter accumulation in wet meadows is always less than 40 cm. Anaerobic conditions lead to the formation of hydric soils which may exhibit gleying and/or mottling and oxidized root channels. These features can be used to delineate wet meadows from dry meadows.

Wet meadows are characterized by herbaceous communities. They are often dominated by graminoids, although forb cover may be substantial, especially at higher elevations. Wet meadow can occur as part of riparian mosaics, interspersed with shrublands, or as large shrubless meadows. Plant communities in wetland meadow systems are adapted to soils that may be flooded or saturated throughout the growing season. They may also occur on areas with soils that are only saturated early in the growing season, or intermittently.

Because wet meadows occupy wide range of elevational and environmental gradients, plant communites and species composition is highly variable. While some communites and species are confined to the alpine, others are found only at montane elevations, and still others span the entire elevational range. Characteristic species in the alpine and upper subalpine include mountain sedge (Carex scopulorum), sheep sedge (C. illota), hair-like sedge (C. capillaris), black alpine sedge (C. nigricans), Drummond's rush (Juncus drummondii), marsh marigold (Caltha leptosepala),brook saxifrage (Saxifraga odontoloma), Parry's clover (Trifolium parryi) and icegrass (Phippsia algida). At subalpine to upper montane elevations, water sedge (Carex aquatilis), and beaked sedge (C. utriculata), either separately or in combination, form a broadly distributed characteristic community. Other common species of this zone include smallwing sedge (C. microptera), analogue sedge (C. simulata), tufted hairgrass (Deschampsia cespitosa), fewflower spikerush (Eleocharis quinqueflora), and bluejoint reedgrass (Calamagrostis canadensis). Combinations of heartleaf bittercress (Cardamine cordifolia), tall fringed bluebells (Mertensia cilliata), and/or arrowleaf ragwort (Senecio triangularis) form a common forb assosciation. Other characteristic forbs include elephanthead lousewort (Pedicularis groenlandica), American globe-flower (Trollius laxus), American speedwell (Veronica americana), fringed grasss of Parnassus (Parnassia fimbriata), American bistort (Polygonum bistortoides) and large leaf avens (Geum macrophyllum). Typical dominants at mid to lower montane elevations include clustered field sedge (Carex praegracilis), Nebraska sedge (C. nebrascensis), woolly sedge (C. pellita), common spikerush (Eleocharis palustris), mountain rush (Juncus balticus var. montanus). Low growing shrubby cinquefoil (Dasiphora fruticosa ssp. floribunda or Pentaphylloides floribunda) is one shrub that can represent significant cover within wet meadows.

Animal species reported for this wetland system include Nokomis Fritillary (Speyeria Nokomis), Wood Frog (Rana sylvatica),Western chorus frog (Pseudacris triseriata), Boreal toad (Bufo boreas), Sora (Porzana Carolina), Virginia Rail (Rallus limicola), common snipe (Gallinago gallinago), Northern Harrier (Circus cyaneus), Willet (Catoptrophorus semipalmatus), meadow vole (Microtus pennsylvanicus), western jumping mouse (Zapus princeps), masked shrew (Sorex cinereus), montane shrew (S. monticolus) and water shrew (S. palustris).

Hydrologic regime is generally the most important factor influencing vegetation patterns and dynamics in wet meadows. Wet meadow development along riparian areas is driven by the magnitude and frequency of flooding, valley and substrate type, and beaver, while in other areas, development is mostly driven by the presence of a seasonally high water table. Flooding disturbance can alter channel morphology through erosion and deposition of sediment to produce floodplain landforms that can either eliminate or provide the template that influences wet meadow system development. Disturbances from animals can also have significant ecological influence on wet meadows. Livestock grazing can alter competitive interactions between plant species resulting in altered community composition. Beaver activity in broad valleys influences vegetation structure and composition and system hydrology. By impounding surface flows in dams, Beaver create open water habitat that is colonized by herbaceous vegetation. Depending on the duration of saturation and flooding these vegetation types are either marshes or wet meadows.

Non-native species can displace native species, alter hydrology, alter structure, and affect food web dynamics by changing the quantity, type, and accessibility to food for fauna. Wetland dominated by non-native, invasive species typically support fewer native animals. Wet meadows are susceptible to invasion by many non-native species, especially pasture grasses such as Kentucky bluegrass (Poa pratensis) and timothy (Phleum pratense) as well as exotics species common to other wetland types such as Canada thistle (Cirsium arvense) and dandelion (Taraxacum officinale). Reed canary grass (Phalaris arundinacea) and giant reed (Phragmites communis) are also common exotics in wet meadows. Native increasers such as mountain rush (Juncus arcticus), wild iris (Iris missouriensis), silverweed (Argentea anserina), and shrubby cinquefoil (Dasiphora floribunda) often increase with overgrazing and or changes in the water table.

Threats include hydrologic and vegetation alteration and landscape fragmentation. Anthropogenic activities that result in increased or decreased drainage, vegetation clearing, mining, excessive livestock grazing, and nutrient inputs all may diminish the condition of the wet meadow system. Activities that fragment the landscape, altering the movement of water or organisms through the system, disconnect wet meadows from their surrounding landscape and may change system composition, structure and function. Wet meadows are often highly vulnerable to invasion by nonnative plant species and are hotspots of exotic species richness Additionally, hydrologic or physical site disturbances, such as may occur from overgrazing, may result in an increase in species such as mountain rush (Juncus balticus var. montanus) and shrubby-cinquefoil (Dasiphora fruticosa ssp. floribunda). Beaver are important drivers of hydrologic function. Their loss from trapping or habitat degradation can lead to significant changes in hydrology and vegetation.

Global climate change is altering the snowmelt-driven hydrology of both mountain and intermountain basins. Snowmelt at high elevations contributes a large proportion of water to most wetland types through its influence on groundwater and surface water dynamics. Climate change is resulting in unprecedented snowpack declines, springtime warming, more precipitation falling now as rain rather than snow and earlier snowmelt. These changes may signal a fundamental shift from precipitation to temperature as the dominant influence on western snowpack. The increasing role of warming on large-scale snowpack variability and trends foreshadows fundamental impacts on streamflow and water supplies across the western United States.