Algific talus slopes comprise a very rare, fragile

ecosystem An ecosystem (or ecological system) is a system formed by Organism, organisms in interaction with their Biophysical environment, environment. The Biotic material, biotic and abiotic components are linked together through nutrient cycles and en ...

and

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

initially believed to exist only in the

Driftless Area The Driftless Area, also known as Bluff Country and the Paleozoic Plateau, is a topographic and cultural region in the Midwestern United States that comprises southwestern Wisconsin, southeastern Minnesota, northeastern Iowa, and the extreme ...

Minnesota Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the so ...

Wisconsin Wisconsin ( ) is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest of the United States. It borders Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michig ...

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...

, and especially,

Iowa Iowa ( ) is a U.S. state, state in the upper Midwestern United States, Midwestern region of the United States. It borders the Mississippi River to the east and the Missouri River and Big Sioux River to the west; Wisconsin to the northeast, Ill ...

.Cliff/Talus System: Southern Floristic Region

Minnesota Department of Natural Resources The Minnesota Department of Natural Resources, or Minnesota DNR, is the agency of the U.S. state of Minnesota charged with conserving and managing the state's natural resources. The agency maintains areas such as state parks, state forests, rec ...

, Retrieved July 24, 2007 More recently, other algific talus slopes have been identified in the

Allegheny Mountains The Allegheny Mountain Range ( ) — also spelled Alleghany or Allegany, less formally the Alleghenies — is part of the vast Appalachian Mountain Range of the Eastern United States and Canada. Historically it represented a significant barr ...

West Virginia West Virginia is a mountainous U.S. state, state in the Southern United States, Southern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States.The United States Census Bureau, Census Bureau and the Association of American ...

. It has been suggested that close comparison with similar sites worldwide may enlarge the distribution, or that the term may become restricted to the flora and fauna characteristic of these zones within the Driftless Area.

Description

''Algific'' means "cold producing" while "

talus slope Scree is a collection of broken rock fragments at the base of a cliff or other steep rocky mass that has accumulated through periodic rockfall. Landforms associated with these materials are often called talus deposits. The term ''scree'' is ap ...

" refers to a collection of talus or broken rock which rests near the surface it detached from. A related term is maderate cliff, which is an algific slope lacking talus. They were first described in the early 1980s.Driftless Area National Wildlife Refuge Comprehensive Conservation Plan

United States Fish and Wildlife Service The United States Fish and Wildlife Service (USFWS or FWS) is a List of federal agencies in the United States, U.S. federal government agency within the United States Department of the Interior which oversees the management of fish, wildlife, ...

, Retrieved July 24, 2007 (This is very good source, but can take a long time to download) These ecosystems can only exist in regions displaying

karst topography Karst () is a topography formed from the dissolution of soluble carbonate rocks such as limestone and Dolomite (rock), dolomite. It is characterized by features like poljes above and drainage systems with sinkholes and caves underground. Ther ...

. Algific talus slopes are found mainly on north-facing slopes of ridges and canyons and are characterized by crumbly, heavily fissured, and porous exposed bedrock, with an overburden of talus remaining ''in situ'' from where it detached from its underlying bedrock; it may also display

scree Scree is a collection of broken rock fragments at the base of a cliff or other steep rocky mass that has accumulated through periodic rockfall. Landforms associated with these materials are often called talus deposits. The term ''scree'' is ap ...

, which is talus finding its narrowest

angle of repose The angle of repose, or critical angle of repose, of a granular material is the steepest angle of descent or Strike and dip, dip relative to the horizontal plane on which the material can be piled without slumping. At this angle, the material ...

down-canyon. This is a "unique system involving ridgetop

sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are also known as shakeholes, and to openings where surface water ...

s and subterranean

ice cave An ice cave is any type of natural cave (most commonly lava tubes or limestone caves) that contains significant amounts of perennial (year-round) ice. At least a portion of the cave must have a temperature below 0 °C (32 °F) all ye ...

s; this system also supports Maderate Cliffs." The valleys in which they occur tend to be very steep, and often have dense forest cover.

Climate

In summer, the cooler talus-covered slopes power an air exchange with sinkholes atop the ridge, with warm air entering the sinkhole to an ice cave. The air is cooled and vented on the algific slope. In winter, the airflow is reversed. Cool or cold air is drawn through the algific talus into the ice cave, with flowing water or atmospheric humidity being turned to ice. The air temperature on these slopes ranges from "30 degrees F to 55 degrees F spring to fall". This causes a cooler, more moist summer environment than that which may occur a relatively short distance away. The result is a rather

boreal ecosystem A boreal ecosystem is an ecosystem with a subarctic climate located in the Northern Hemisphere, approximately between 50° and 70°N latitude. These ecosystems are commonly known as taiga and are located in parts of North America, Europe, and Asia ...

more associated with that found to the north at the Canada–US border. It can also host relict populations not found elsewhere locally. "The vegetative community on algific talus slopes is different than the surrounding forest and typically contains ferns, mosses,

liverwort Liverworts are a group of non-vascular land plants forming the division Marchantiophyta (). They may also be referred to as hepatics. Like mosses and hornworts, they have a gametophyte-dominant life cycle, in which cells of the plant carry ...

s, evergreen species such as

Canada yew ''Taxus canadensis'', the Canada yew or Canadian yew, is a conifer native to central and eastern North America, thriving in swampy woods, ravines, riverbanks and on lake shores. Locally called simply as "yew", this species is also referred to as ...

and

balsam fir ''Abies balsamea'' or balsam fir is a North American fir, native to most of eastern and central Canada (Newfoundland west to central Alberta) and the northeastern United States (Minnesota east to Maine, and south in the Appalachian Mountains to ...

birch A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech- oak family Fagaceae. The genus ''Betula'' contains 3 ...

basswood ''Tilia americana'' is a species of tree in the family Malvaceae, native to eastern North America, from southeast Manitoba east to New Brunswick, southwest to northeast Oklahoma, southeast to South Carolina, and west along the Niobrara River to ...

, and

sugar maple ''Acer saccharum'', the sugar maple, is a species of flowering plant in the soapberry and lychee family Sapindaceae. It is native to the hardwood forests of eastern Canada and the eastern United States. Sugar maple is best known for being the ...

, and boreal disjunct herbs and ferns."

Distribution

The only sites in Wisconsin are "the Western Coulee and Ridges Ecological Landscape in western Grant County and are within a few miles of the Mississippi River". The great majority of the protected sites are closed to the general public, and in fact, are notably undocumented on the net, in order to keep them out of the eye of those who would vandalize them. One place that can be visited, however, is

Bixby State Preserve Bixby State Preserve is a nature reserve located in southwestern Clayton County, Iowa, in the midwestern United States. It is located north of Edgewood. It is operated by the Iowa Department of Natural Resources as one of the Iowa state pres ...

, in southwestern

Clayton County, Iowa Clayton County is a County (United States), county located in the U.S. state of Iowa. As of the 2020 United States census, 2020 census, the population was 17,043. Its county seat is Elkader, Iowa, Elkader. The county was established in 1837 and ...

Endangered and threatened species

The Iowa Pleistocene Snail was believed extinct until it was discovered on algific talus slopes in northeast Iowa in 1955. Placed on the

Endangered Species List On 29 January 2010, the IUCN Red List of Threatened Species identified 5220 (2754 animals, 1 fungus, 2464 plant, 1 protist) endangered species, subspecies and varieties, stocks and sub-populations. For IUCN lists of endangered species by kingdo ...

in 1977, Congress created the

Driftless Area National Wildlife Refuge Driftless Area National Wildlife Refuge is a United States National Wildlife Refuge in northeastern Iowa, southwestern Wisconsin and northwestern Illinois. It is a collection of non-contiguous parcels in the vicinity of the Upper Mississippi ...

in 1989 to protect this species, as well as other threatened and relict species. Much of this refuge was carved out of pre-existing protected areas, most notably the

Upper Mississippi River National Wildlife and Fish Refuge The Upper Mississippi River National Wildlife and Fish Refuge is a , See also * Izaak Walton League * List of National Wildlife Refuges *Trempealeau National Wildlife Refuge Trempealeau National Wildlife Refuge is a National Wildlife Refuge ...

. The Northern monkshood is a threatened wildflower in the buttercup family (

Ranunculaceae Ranunculaceae (, buttercup or crowfoot family; Latin "little frog", from "frog") is a family (biology), family of over 2,000 known species of flowering plants in 43 genera, distributed worldwide. The largest genera are ''Ranunculus'' (600 spec ...

) occurring in the Driftless Area as well as in New York State and receives similar protection. Algific talus slopes have also been posited to harbor rare lichen species.

References

{{Reflist

External links

Algific Talus Slope

Wisconsin Department of Natural Resources The Wisconsin Department of Natural Resources (WDNR) is a government agency of the U.S. state of Wisconsin charged with conserving and managing Wisconsin's natural resources. The Wisconsin Natural Resources Board has the authority to set polic ...

, Retrieved July 24, 2007
Mountain Maple Hollow
The

Nature Conservancy The Nature Conservancy (TNC) is a global environmental organization headquartered in Arlington, Virginia, United States. it works via affiliates or branches in 79 countries and territories, as well as across every state in the US. Founded in ...

of Iowa, Retrieved July 24, 2007 *Bill Witt
"An ecosystem frozen in time"
Iowa Natural Heritage Foundation, Retrieved July 24, 2007
The Ice Age Persists in the Upper Midwest, Where the Hills Breathe, Atlas Obscura
, Retrieved May 21, 2021 +Algific Driftless Area">+Algific Taiga and boreal forests in the United States Ecoregions of the United States">Taiga and boreal forests in the United States">Driftless Area">+Algific Taiga and boreal forests in the United States Ecoregions of the United States Rock formations of Minnesota Rock formations of Wisconsin Landforms of Iowa Landforms of Illinois Rock formations of West Virginia