Spring has arrived. The cheerful song
of the American Robin wakes me up each morning, their is enough daylight for late afternoon frivolities, and the Western Chorus frogs are
calling so jubilantly into the night now that they would put me to sleep if I
wasn’t so excited to hear them. I open the window and cock my ear to the side
to take in the sound that is occasionally audible over the constant grumble of the highway! In the
woods the Bigleaf Maple flowers are popping out of their over-sized buds and the
birches have given their last drops of sweet water. Like the leggy frogs that
leap enthusiastically in the warm air after a winter burrowed in frigid mud,
the plants too seem to be springing from the ground. Nettles grow visibly
between my every-other day harvests and an often overlooking edible—Giant Horsetail—claims
its place in the front of the seasonal line-up of tasty shoot vegetables.
In the Pacific Northwest we have
several species of horsetail. Two are edible, three are useful as sandpaper,
and the remaining are neither useful to humans, nor common (limited to sloughs
and marshes). Following are descriptions of the edible species.
Giant Horsetail
(Equisetum telmateia) description
Giant Horsetail is an herbaceous
clonal species. New shoots emerge from an underground network of rhizomes
beginning in early to mid-March. There are two types of shoots, the fertile
(spore bearing) shoots appearing a week ahead of the vegetative shoots.
Fertile shoots are ½-3/4” (1.5-2 cm) wide and 1-2’ (30-60 cm) tall. The stems elongate
between nodes which are covered with papery brown bracts. At the top of each
fertile shoot is a cone-like structure (strobilus) that changes from green to
white and eventually matures to brown when it begins releasing spores. The
vegetative shoots are slightly narrower and taller at 3/16-3/4” (5-20 mm) wide
and 1.5-4’ (50-120 cm) tall. The nodes of the vegetative shoots are also surrounded
by brown papery bracts, but they smaller giving room for the rings of needle
like leave that give the plant its namesake appearance. The features that
distinguish Giant Horsetail are most easily noticed in cross-section. A cross
section of the vegetative shoots shows a large hollow center that is much wider
than twice the thickness of the walls, and a cross section of the needle like
leaves shows that they are rounded. |
| This oddball has both photosynthetic branches and a reproductive strobilus |
Giant Horsetails grow at low
elevations in loose, damp soil. They are found from Bella Coola and Haida Gwaii
in British Columbia southward along the coast to Southern California. Their
eastward range is limited by the Coast Range in BC, and the Cascades in
Washington and Oregon, except for a few isolated inland populations in the
Columbia River watershed. This pattern continues into California where they flourish
along the Coast Range but have only limited distribution in the Sierra
foothills.
Edibility
 |
| Still OK (center); too old (right) |
 |
| Perfect stage (left) |
The fertile shoots of Giant
Horsetails are best picked between March 15th and April 15th.
At this time they are 4-8” (5-10 cm) tall and the cones are still whitish.
Before this time they are hard to see and too small to be worth the effort, and
after this time they become stringy. Palatability plummets after the cones brown.
Pluck shoots at ground level and carefully peel off the coarse bract that surrounds
each node. These bracts are filled with silicates that will sand away at your
teeth, an anti-herbivory adaptation that usually keeps the deer from eating them
unless they are really hungry. Once you have peeled the shoots, discard the strobilus,
rinse off any dirt, and enjoy them fresh. Their mild flavor and juiciness is
similar to celery, but they lack the annoying fibers. I didn’t learn to eat Giant
Horsetails until nine years ago when my friend Trent picked one at the Outback
Farm ate it. They have been among my favorite wild shoot vegetables ever since.
 |
| Unprocessed vegetative shoots (left) and fertile shoots (right) |
 |
| Perfectly ripe and peeled |
The vegetative shoots of Giant
Horsetail are also edible, but much more work for a product that is not as
tasty. You must pick them before the needle like leaves have started to extend
horizontally. Remove both the bracts (as above) and the leaves since the leaves contain the same silicate grazing defense
as the bracts.
Ethnobotany
Closely related species often are
used in very similar ways. Most Rubus fruits
are choice edibles and most willows provide good withes for basket weaving. So
too is the ethnobotany of horsetails. When I skimmed through Daniel Moerman’s “Native
American Ethnobotany” I quickly realized that Indigenous societies across the
continent traditionally use E. arvensis,
E. telmateia, and E. hymenale for similar things such as skin
poultices, tonics for internal organs and sandpaper. However, a few accounts
such suggest that the very coarse stems of Scouring Rush (E. hymenale) where traditionally eaten
as medicine, and I suspect that this is a case of mistaken identity on the
part of the ethnobotanist. The plants all share similar habitat and appearance,
making identification without a reference specimen challenging.
The fertile shoots of Giant Horsetail
are traditionally pealed and eaten by Indigenous groups from the Yurok in
California to the Nuu-chah-nulth on the West Coast of Vancouver Island, and
several in between (Moerman). Further north along the coast, the plant is less
common; while it is still recognized, it is apparently not eaten (see Turner
2010; Turner and Bell 1973). The Makah (Gill 1983), Nitinaht, Nuu-chah-nulth (Turner
et al. 1983; but see Turner and Efrat 1872), and Clallam (Gunther 1973) eat
both the fertile and vegetative shoots. The Makah also eat the young strobilus
after boiling it for 10 minutes, and have a special name for the reproductive
shoots that reflects the “head” on the top (Gill 1983). In earlier times, the
tubers were evidently collected later in the season and eaten raw by the Makah
(Swan 1870), Cowlitz, and Swinomish (Gunther 1973), or boiled and served with
grease by the Makah, Clallam, Quinault, Cowlitz, and Lower Chinook (Gunther
1973; Fleisher 1980). The early naturalist and ethnographer George Gibbs (1863) provides a name for horsetail roots in Clallam and Lummi. Gibbs (1877) also gives a name in Nisqually and Skykomish with the translation "ground grape (the tuber of a species of Equisetum)." The Cowlitz also pulverized the dried cones to mix with
salmon eggs (Gunther 1973). The shoots are universally
regarded as juicy and thirst quenching but I can find no descriptions of the taste of the tubers (and have not yet seen or tried them myself).
The name horsetail aptly reflects
the similarity in appearance of the vegetative shoots to a horse’s tail. This
resemblance is also captured in the genus name which means “horse bristle” in
Latin. The species epithet comes from the Greek word telmat which means “wetland,” where the plants are often found. A
geographically distinct subspecies of Giant Horsetail is found in Europe,
Western Asia, and North Africa and retains the subspecies name telmateia whereas our western North
American taxon goes by the subspecies name braunii
(in honor of the German botanist Alexander Carl Heinrich Braun,
1805-1877, who specialized in spermophytes).
 |
| A week too late |
Related
species: Common Horsetail (Equisetum
arvense)
Common Horsetails are widespread
throughout North America. From a distance, they can be
distinguished from Giant Horsetail by their smaller size, more kinked needles,
and longer primary (inner most) leaf segments on each branch. In cross section,
the needle like leaves are angled so strongly that they appear winged, and the
void in the middle of the main stem is equal to or less than twice the wall
thickness. The fastidious will also find that Giant Horsetails have 20-40
ridges around the stem while the Common variety have 10-15. At harvest time, the
shoot thickness and wall to central void ratio are the most discernible
differences. Fertile shoots of Common Horsetail can be peeled and eaten in the
same manner as Giant Horsetail. They are more work for less reward, and I find
them to also be less tasty. The young vegetative shoots may well be edible as
above, but frankly, I can’t see how they would be worth the trouble when the
fertile shoots are available.
 |
| E. telmateia x-section |
 |
| E. arvense x-section |
The species epithet arvense comes from the Latin adjective “in the field,”
an apt name for this common agricultural “weed.”
Bibliography
Fleisher, Mark 1980. The
Ethnobotany of the Clallam Indians of Western Washington. Washington State
University.
Gibbs, George 1863. Alphebetical vocabulary of the Clallam and Lummi.
Gibbs, George 1877. Tribes of Western Washington.
Gibbs, George 1863. Alphebetical vocabulary of the Clallam and Lummi.
Gibbs, George 1877. Tribes of Western Washington.
Gill, Steven 1983. Ethnobotany of
the Makah and Ozette People, Olympic Peninsula, Washington. Washington State
University, PhD. Thesis.
Gunther, Erna 1973. Ethnobotany
of Western Washington. University of Washington Press, Seattle WA.
Moerman, Danielle. Native American Ethnobotany database.
University of Michigan, Deerborn.
Swan, James 1880. The Indians of
Cape Flattery, at the Entrance to the Straight of Fuca, Washington Territory.
Smithsonian Contributions to Knowledge, Collins Printer, Philadelphia PA.
Turner, Nancy J. 2010. Plants of
Haida Gwaii. Sononis Press, Winlaw BC.
Turner, Nancy J. and Barbara
Efrat 1982. Ethnobotany of the Hesquiate Indians of Vancouver Island. Cultural
Recovery Papers No. 2, British Columbia Provincial Museum.
Turner, Nancy J., John Thomas,
Barry F. Carlson, and Robert T. Obilvie 1983. Ethnobotany of the Nitinaht
Indians of Vancouver Island. Occasional Papers Series No. 24, British Columbia
Provincial Museum.
Turner, Nancy J. and Marcus Bell
1973. Ethnobotany of the Southern Kwakiutl Indians. Economic Botany, Vol 2, No
3.
