"Cranberry cultivation has the potential to result in loss and degradation of wetlands, lakes and streams and their associated wildlife, fish and other aquatic life." [1]
Commercialized
cranberry farming comes at a high price for the ecosystem surrounding
the bog. Through the clearing and draining of wetlands and
woodlands,
dam, reservoir, ditch, and dike construction, and application of
herbicides, insecticides, and fungicides, area flora and fauna suffer
from loss of
habitat and targeting. Thus, the overall ability of the ecosystem
to perform vital functions and services is threatened by commercial
cranberry farming.
Clearing & Draining of Wetlands and Woodlands:
[2]
[3]
"Cranberry beds currently occupy approximately 15,000 acres of former wetlands in Wisconsin. The industry has about 23,000 acres of reservoirs statewide, and much of this acreage is former wetland." [4] Cranberries are a water-intense crop. An estimated six acre-feet per year per acre of vine is necessary for productivity, making land with high water tables (wetland and woodland acreage) the most economical sites for bogs.[5] On the St. Croix, it is a combination of the two. Wetlands and woodlands near the river are cleared, and the river serves as the main body of water used for flooding the bogs. As you can see, vegetation is literally "cleared of vegetation, scalped, and leveled approximately two feet below the existing grade of the soil," [6] instigating a chain of events that bring down the function of the ecosystem: ecosystem services (especially natural filtration, which is the crucial serivice of wetlands) are no longer provided due primarily to lack of flora that mitigates nutrient usage, topsoil is left vunerable to wind and water (implying the consequences of runoff wherever it happens to be carried), and area fauna (including deer, geese, beavers, otters, mink, squirrels, turtles, owls, insects, etc) are at a loss for food and habitat. In essence, 38,000 acres of healthy and vital ecosystem service has been forfeited to the commerical cranberry industry.
Dam, Reservoir, Ditch, and Dike Construction
[7]
[8]
[2]
[3] "Cranberry beds currently occupy approximately 15,000 acres of former wetlands in Wisconsin. The industry has about 23,000 acres of reservoirs statewide, and much of this acreage is former wetland." [4] Cranberries are a water-intense crop. An estimated six acre-feet per year per acre of vine is necessary for productivity, making land with high water tables (wetland and woodland acreage) the most economical sites for bogs.[5] On the St. Croix, it is a combination of the two. Wetlands and woodlands near the river are cleared, and the river serves as the main body of water used for flooding the bogs. As you can see, vegetation is literally "cleared of vegetation, scalped, and leveled approximately two feet below the existing grade of the soil," [6] instigating a chain of events that bring down the function of the ecosystem: ecosystem services (especially natural filtration, which is the crucial serivice of wetlands) are no longer provided due primarily to lack of flora that mitigates nutrient usage, topsoil is left vunerable to wind and water (implying the consequences of runoff wherever it happens to be carried), and area fauna (including deer, geese, beavers, otters, mink, squirrels, turtles, owls, insects, etc) are at a loss for food and habitat. In essence, 38,000 acres of healthy and vital ecosystem service has been forfeited to the commerical cranberry industry.
Dam, Reservoir, Ditch, and Dike Construction
[7]
[8] "...Because
the primary purpose of the reservoir is to provide water for cranberry
cultivation, water level fluctuations may occur which may be harmful to
aquatic and wildlife species." [9] It doesn't just rain enough
that six acre-feet per year per acre of vine of water is available for
commercial cranberry farming in any given area along the St. Croix.
Instead, water is drawn from the (approximately) 53 St. Croix
River dams and managed in reservoirs built by the cranberry farmers
with state permits. The environmental impacts of such dams,
reservoirs, and ditches (shown in the right picture) are well known.
Upstream, dam construction leads to loss of habitat for
terrestrial flora and fauna, as the seasonal fooding regime is altered
due to the reservoir. Both aquatically and terrestrially,
the environment offered by a reservoir (lake-like) provides
conditions for an extremely limited variety of species, as opposed to
the natural regime (river-like) that offers a much more diverse set of
conditions that can foster greater biodiversity. Additionally,
the temperature changes and sediment control that are implicit with
reservoirs affect the downstream health of the river. For example
and among other things, fish spawning cycles are threatened, and
sediment builds up in the reservoir such that it's a strong pollutant
while downstream ecosystems suffer from the lack thereof.
Collectively, these events lead
to decreased stability of the food chain and, thus, declining health of
the ecosystem in and around the river. Comprehensively, each dam
and reservoir constructed for commercial cranberry farming along the
St. Croix has had these effects on its surrounding environment.
Ditches and dikes constructed by cranberry farmers have many of
the same implications (loss of vegetation, instability of the food
chain, decreased biodiversity, and plummeting effectiveness and health
of the ecosystem), as they, too, alter the natural state of an
ecosystem.
Application of Chemicals: 
[10]
[11]
[12]
“Native and introduced plant species are considered weeds when they invade managed cranberry beds." Unfortunately for the flora and fauna of cranberry bogs, herbicides, insecticides and fungicides are implicit for commerical cranberry farming. Herbicides are defined as "chemical substances used to destroy or inhibit the growth of plants," while insecticides, and fungicides are defined as "chemical substances used to destroy or inhibt the growth of insects [and fungi]," respectively. For maximum productivity, cranberry bogs must be virtually free of any species of flora or fauna that may inhabit a bog. Otherwise, up to eighty percent of productivity could be sacrificed. [13] To avoid this, farmers run a rigid schedule of chemical spraying. However, even under the watchful eye of the WDNR, the Wisconsin Integrated Pest Management Program, the Wisconsin Department of Agriculture, Trade, and Consumer Protection (DATCP), the EPA, and others, chemical use has raised concerns because Wisconsin studies have repeatedly published frightening results. For instance, one "found elevated concentrations of lead, arsenic, cadmium, selenium, and other toxic metals in cranberry bog discharges, and there are approximately twenty-two pesticides commonly used on cranberries, including napropromide, norflurazon, dichlovenil, 2, 4-D, carbaryl, diazinon, chlorpyrifos, and azinphos-methyl." [14] (For a complete list, see link below.) By inhibiting the growth of all plant species other than the cranberry, farmers are ensuring a lack of food supply for area fauna. Furthermore, farmers are directly reducing that food source by killing off insects and worms in their bogs, even those that are native! An additional concern is bioaccumulation of those chemicals in species that do encounter them and survive (killdeer, loons, rabbits, etc). Again, by hindering the growth of vegetation, ecosystem effectiveness and health declines. Below are a few pictures of the most common fauna destroyed by cranberry farmers, the most prominent along the St. Croix being Goldenrod.
[10]
[11]
[12]“Native and introduced plant species are considered weeds when they invade managed cranberry beds." Unfortunately for the flora and fauna of cranberry bogs, herbicides, insecticides and fungicides are implicit for commerical cranberry farming. Herbicides are defined as "chemical substances used to destroy or inhibit the growth of plants," while insecticides, and fungicides are defined as "chemical substances used to destroy or inhibt the growth of insects [and fungi]," respectively. For maximum productivity, cranberry bogs must be virtually free of any species of flora or fauna that may inhabit a bog. Otherwise, up to eighty percent of productivity could be sacrificed. [13] To avoid this, farmers run a rigid schedule of chemical spraying. However, even under the watchful eye of the WDNR, the Wisconsin Integrated Pest Management Program, the Wisconsin Department of Agriculture, Trade, and Consumer Protection (DATCP), the EPA, and others, chemical use has raised concerns because Wisconsin studies have repeatedly published frightening results. For instance, one "found elevated concentrations of lead, arsenic, cadmium, selenium, and other toxic metals in cranberry bog discharges, and there are approximately twenty-two pesticides commonly used on cranberries, including napropromide, norflurazon, dichlovenil, 2, 4-D, carbaryl, diazinon, chlorpyrifos, and azinphos-methyl." [14] (For a complete list, see link below.) By inhibiting the growth of all plant species other than the cranberry, farmers are ensuring a lack of food supply for area fauna. Furthermore, farmers are directly reducing that food source by killing off insects and worms in their bogs, even those that are native! An additional concern is bioaccumulation of those chemicals in species that do encounter them and survive (killdeer, loons, rabbits, etc). Again, by hindering the growth of vegetation, ecosystem effectiveness and health declines. Below are a few pictures of the most common fauna destroyed by cranberry farmers, the most prominent along the St. Croix being Goldenrod.
Reed Canary Grass Squirrel Tail Grass Bog Laurel Quaking Aspen Goldenrod Narrow Leaved Cattail Devil's Beggartick
Links:
Environmental Issues Related to Cranberry Production in Wisconsin
http://www.library.wisc.edu/guides/agnic/cranberry/documents/dnrpaper.html
Wisconsin Cranberry Weeds
http://www.hort.wisc.edu/cran/mgt_articles/articles_pest_mgt/weeds/cranweeds.html
Pesticides Approved for Cranberry Industry in the state of Wisconsin
http://www.hort.wisc.edu/cran/PestWeb/Cranberry%20Labels/Cranberry%20Chemicals.htm
Environmental Issues Related to Cranberry Production in Wisconsin
http://www.library.wisc.edu/guides/agnic/cranberry/documents/dnrpaper.html
Wisconsin Cranberry Weeds
http://www.hort.wisc.edu/cran/mgt_articles/articles_pest_mgt/weeds/cranweeds.html
Pesticides Approved for Cranberry Industry in the state of Wisconsin
http://www.hort.wisc.edu/cran/PestWeb/Cranberry%20Labels/Cranberry%20Chemicals.htm
