VALUE AND USE
SPECIES: Polystichum munitum | Western Sword Fern 



WOOD PRODUCTS VALUE : 
NO-ENTRY


IMPORTANCE TO LIVESTOCK AND WILDLIFE : 
Wildlife:  Western sword fern provides forage for elk, deer, and black
bear [28].  In coastal Oregon forests it is one of the ten most
frequently used foods of Roosevelt elk [6,24].  On the Olympic peninsula
of Washington, the fronds are eaten yearlong and are of medium
importance to Roosevelt elk.  Its use is moderately heavy in winter when
snow depth permits grazing.  In one study, it was found in eight of nine
Roosevelt elk stomachs sampled and accounted for 9.2 percent of the
total food volume eaten [60].  In Oregon western sword fern is a
preferred food of mountain beaver [44].

Livestock:  Ferns are a very minor part (<2%) of sheep diets in western
Oregon [47].


PALATABILITY : 
The palatability of western sword fern is rated as fair for Roosevelt elk
on the Olympic Peninsula of Washington [60].


NUTRITIONAL VALUE : 
Western sword fern has particularly high levels of potassium and
nitrogen when it occurs as an understory plant in seral red alder (Alnus
rubra) stands.  Calcium, phosphorus, and magnesium levels are higher in
the understory of seral red alder stands than in the understory of
Douglas-fir stands [13,76].


COVER VALUE : 
NO-ENTRY


VALUE FOR REHABILITATION OF DISTURBED SITES : 
NO-ENTRY


OTHER USES AND VALUES : 
Western sword fern is cultivated as an ornamental plant and is well
suited to a variety of garden situations.  Its fronds are harvested in
quantity for florists to use as background greenery [19,40].  The fronds
are edible when very young [17].


MANAGEMENT CONSIDERATIONS : 
Western sword fern is not generally considered a serious competitor for
conifers.  However, in localized areas where it is particularly abundant
and vigorous, it can interfere with conifer regeneration and growth.
Reduction or removal of western sword fern may reduce competition for
moisture and light in these situations [28].  In laboratory and field
trials, it did not allelopathically inhibit other plants [15].

In coastal Douglas-fir forests western sword fern cover is greatly
reduced by accumulations of heavy slash and soil disturbance during
logging [6,24].  Western sword fern dominated only undisturbed
microsites following clearcutting in western hemlock (Tsuga
heterophylla), Douglas-fir, and western red-cedar (Thuja plicata)
forests with western sword fern-Oregon oxalis (Oxalis oregana)
understories.  On disturbed plots western sword fern cover was under 10
percent for the first 5 years and then began to increase.  Following
burning, cover was reduced to 0.5 percent [6].  In Sitka spruce (Picea
sitchensis)-hemlock (Tsuga spp.) forests, overall cover of western sword
fern generally increased on thinned plots [3].

Western sword fern is resistant to most herbicides, although its
response is intermediate to high glyphosate concentrations [10].
Western sword fern cover was reduced but still abundant following
various treatments in Oregon.  The treatments included applications of
2,4,5-T and picloram followed by crushing in one area and burning in
another.  It also recovered well following spraying with glyphosate;
however, it almost disappeared from plots that were severely scarified
[44].  Dicamba and bromacil are effective herbicides on western sword
fern, although dicamba will cause injury to trees [49,67].  Late spring
is the most efficient time to treat it with dicamba, as twice as much
dicamba is needed in midsummer.

In Oregon presence of western sword fern is one of the indicators used
to predict the relative difficulty of conifer regeneration.  A range of
1 to 14 has been developed, with higher values indicating better
regeneration.  After clearcutting in Oregon, western sword fern presence
had an indicator value of 11, while after partial cuting its value was
2.  This same scale is used to indicate relative temperature conditions
in undisturbed stands [26].  In southwestern British Columbia western
sword fern is an indicator species in two associations used to estimate
Douglas-fir site index.  These associations indicate moderately dry to
wet and generally nutrient-rich sites [27].  In western hemlock forests
of Idaho's Clearwater National Forest, clusters of western sword fern or
patches of mixed ferns may indicate areas of excess soil moisture and/or
mass soil movement [58].

Related categories for Species: Polystichum munitum | Western Sword Fern