VALUE AND USE
SPECIES: Carex aquatilis | Water Sedge 



WOOD PRODUCTS VALUE : 
NO-ENTRY


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
Water sedge is grazed by many ungulates, including moose, caribou, and
elk, but it is not a major component of their diet.  Due to the swampy
habitat of water sedge, grazing by most ungulates is limited [43,49,31].
Domestic livestock do not readily graze water sedge areas until the soil
surface dries in late summer [30].  Water sedge is resistant to grazing.

Water sedge habitat provides cover for some birds, waterfowl, and small
mammals [30].  Some particular birds associated with water sedge
habitats include the green-winged teal, the sandhill crane, the common
snipe, the common yellowthroat, the red-winged blackbird, and the song
sparrow [23].


PALATABILITY : 
Palatability of water sedge is good for horses, cattle, and sheep [8];
and fair for white-tailed deer and elk [30].  Palatability for
undomesticated ungulates varies seasonally and ranges from good to poor,
as shown below [16,19,43,49].

    species             palatability             season

Black-tailed deer       fair to poor       March to May
Caribou                 fair               early to midwinter
Musk-ox                 good to fair       summer
Moose                   good to fair       summer and early to midwinter
                                                

For grazing animals, food value of water sedge is generally fair.  Water
sedge and other sedges compose 70 to 80 percent of winter forage for
bison in northern Canada [3].  In Montana, the food value or degree of
use in upland game birds is poor, but fair for waterfowl, small nongame
birds, and small mammals [8,30].  A study of a water sedge community
showed that 40 percent of all water sedge shoots were eaten by lemmings
[3].


NUTRITIONAL VALUE : 
Water sedge serves as excellent forage in arctic areas.  It equals
clover in nutritional value and exceeds it in protein content [31].
Water sedge has also been reported to have fair energy and protein
values.  It is consumed in the winter months by lichen foragers, and
serves as a carbohydrate source [3].  Waterfowl eat the seeds of water
sedge, but they are probably not a major food source [23].

For one growing season, the mean nutrient concentration was measured.
The following are averaged measurements through the growing season [1].
The P/Ca ratio is fair, but the high concentration of calcium rates as
poor.

  Element                  mg per g of dry tissue weight
     K                                13.72
     N                                11.53
     Ca                                4.565
     Mg                                1.385
     P                                 1.256
     Na                                0.618
     Fe                                0.095
     Mn                                0.089
     Zn                                0.058
     Cu                                0.007

In Alaska, water sedge was found to have 5.4 percent protein and 53
percent carbohydrate in May [43].  For caribou, water sedge is a
semiessential dietary item, providing nutrients not present in lichens
[49].


COVER VALUE : 
Water sedge provides poor cover for elk and white-tailed deer [8].
Along streambanks, it provides fair cover for small mammals [48,30], and
water sedge bogs provide fair cover for waterfowl and small nongame
birds.  Waterfowl also use water sedge habitats for nesting cover [30].
The overhanging, rhizomatous masses of sod formed by water sedge on
streambanks provide shade and cover for fish [30].


VALUE FOR REHABILITATION OF DISTURBED SITES : 
Water sedge colonizes disturbed areas including firelines, vehicle
tracks in tundra, and oil spills [7,12,37,47,60].  One year after the
Wickersham fire in 1971 in Alaska, water sedge became abundant in the
firelines but was not found in the burned area.  The dense rhizomatous
mat formed by water sedge helps it withstand winter vehicle traffic and
recover quickly from summer traffic.  Offroad vehicles can cause serious
long-term damage to taiga and other watersedge habitats [7].

Water sedge's potential for erosion control has been rated as medium, as
has its potential for short- and long-term revegetation [8].  Studies
regarding traffic and oil spills have been conducted.  Water sedge
invaded oil-damaged areas well compared with other vascular plants, and
it appeared to have some tolerance to the toxic effects of crude oil
[7,37].  Natural succession at other disturbed sites, including
firelines, and burned and overgrazed areas, occurs rapidly, and sowing
exotic grasses is likely to interfere with, rather than promote, native
plant establishment.  The only exception to this would be where surface
erosion is severe [12].  Herbaceous cover may prevent erosion but will
do little to slow the thawing of underlying permafrost (where present)
[60].

Water sedge responds well to phosphorous fertilizer [47].


OTHER USES AND VALUES : 
NO-ENTRY


MANAGEMENT CONSIDERATIONS : 
Potential biomass production for water sedge is high [8].  Water sedge
is resistant to grazing, but grazing in swampy habitat may result in
soil damage.  Livestock use often results in an increase in hummocking
and pitting of associated soils [52].  When packstock and hiker use
occurs on wet soil, formation of ruts can be severe.  New trails should
be built on adjacent uplands [8].

Related categories for Species: Carex aquatilis | Water Sedge