Beach Pea, An Enigmatic Edible

Ripe Beach Peas in the half shell

I first learned that Beach Peas (Lathyrus japonicus) were edible from my college friend Joe as we were walking along the south shore of Lake Superior. I was a little cautious, having heard the oft repeated admonition that “wild peas are poisonous” but they were ripe and I trusted him, so I picked a few and ate them on the spot. Nothing ill came of it, but having only eaten one, I still always had a question in my mind about just how edible they really are. 

I grew up in the Pacific Northwest only miles from the salt-chuck, but I failed to notice Beach Peas as a part of our regional flora until I moved to Victoria for graduate school. Beach Peas thrive along surf swept shorelines of sand and pebble, and there are many more suitable beaches on Vancouver Island than in Bellingham Bay (though I have since found them scattered throughout the Salish Sea).

Description

Flowers and young Beach Peas

Beach Peas are trailing herbaceous perennial vines that are usually no taller than 18 inches, but can form extensive patches. The leaves are pinnately compound with 3-5 pairs of ovate leaflets, and a terminal tendril that is sometimes branched. Leaflets are usually smooth margined with a mucrinate tip, the upper surface of the leaflets are light green to bluish green and the lower sides are whitish green. A large sagittate stipule surrounds the stem at the base of each leaf. Both leaves and stems are hairless. The stems are somewhat angular but strongly compressed or winged like in some other members of the Lathyrus genus. Pea-like flowers are born in racemes on upright peduncles that usually rise above the surrounding leaves. Each raceme contains 3-5 pairs of light purple to dark pink flowers that begin to bloom in May. Depending on the availability of moisture, flowering can continue into September. Pea pods begin to form as the weather dries out and the first ripe pods are often available in the Puget Sound from mid-late June. Young pods are hairy and green or red with green tips. As the single row of peas mature, the pods blend to a reddish green. Each pod contains 6-10 spherical peas that are about ¼” wide.

Young Beach Pea flowers

Mature pods

Beach Peas are also called Sea Pea, Sea Peavine, and as all variations of the name suggests, are strictly maritime. I typically find them growing in sand or gravel among driftwood, on dunes among the seaward extent of the Dune Grass (Leymus mollis), or more rarely on headlands. They can be found from Alaska to California, across the Arctic, the North Atlantic, and even the Great Lakes, as well Eastern Asia from China northward. Such a broad range is explained by the plant's use of ocean currents for dispersal. The seeds float and can remain viable in salt water for up to 5 years (Ohtsuki et al 2011).

Beach Pea typically grows among driftwood on surf swept shorelines

Edibility

Shelled Beach peas ready to cook

Reputable foragers that say it is safe to eat Beach Pea in small quantities include Euell Gibbons (1964), Sam Thayer (Personal Communication 2014), and Hank Shaw (2013).  Shaw writes that the young shoots, flowers, and peas of a variety of species in the genus Lathyrus are edible. He goes on to explain that the rumors of toxicity can be attributed to Chickling Vetch (L. sativa), a cultivated species of the Old World. Scientific Studies have shown that people that rely on Chickling Vetch for a major part of their diet for several months (such as in times of famine) are prone to a muscle wasting disease called Lathyrism. Shaw concludes that Lathyrus peas when properly prepared and eaten as part of a balanced diet are perfectly safe.

To harvest the peas, bring a good pair of scissors since the stems holding the pea pods are often stronger than the roots, making it easy to accidentally pull the entire plants from their loose substrate when trying to break the pods from the stem. Once you’ve filled your basket, find a shady place to shell peas and enjoy the sound of the waves crashing on the beach. Though small, the peas can be efficiently shelled by tearing off the tip and “unzipping” one side by pulling downward on the strong fiber that runs from the stem to the tip; twist the pod slightly and it will pop open.

Boiled Beach Peas with fresh garnish

My first experience cooking Beach Peas turned out to be a success. I boiled the peas in water for 5 minutes, and then changed the water because I thought it smelled of volatile phytochemicals. After another 5 minutes they were soft and smelled more food-like, so I strained and rinsed them.  Desiring an authentic taste, I ate them plain. They have a thick, mushy texture and mild flavor that is more similar to split peas than sweet peas. Beyond their texture, there is nothing disagreeable about them and I think that they would be delicious with a little butter and salt, or honey on a knife (Anonymous).

Ethnobotany

Flowers and young pods

Interestingly (and contrary to the suggestion by Shaw that they were “used by all sorts of groups… from the Eskimo to the Iroquois) the traditional use of Beach Peas for food by Indigenous Peoples in the Pacific Northwest is poorly documented in the ethnographic literature. Perhaps the best reference comes from one collaborator in Steven Gill’s work with the Makah and Ozette. Makah elder Jim Tollerud said that immature seeds are eaten as peas (Gill 1983, pg. 281). Unfortunately no further details are provided. Erna Gunther did not even mention the plant in the Ethnobotany of Western Washington. Nancy Turner provided a short account in her work with the Haida (2010), Hesquiat (Turner and Efrat 1982), and Dididaht (Turner et al. 1983), but in all cases it was lumped with Giant Vetch (Vicia gigantea) by both name and use, and was poorly regarded as a food. She wrote, “The ‘peas’ of these wild plants were not generally considered to be edible, although Newcombe (1897, 1901) reported that the seeds of young Giant Vetch were eaten, and Norton (1981) said that several of her Kaigani consultants boiled and ate the peas [of Giant Vetch] after the pods were dried, although one woman said that they were dangerous. Some Kwakwaka’wakw were also said to eat [Giant Vetch] (Turner 2010). 

I could only find a few ethnobotanical references in other parts of the plant’s range. The peas are sometimes collected and eaten by the Ainus in Japan (Batchelor and Miyabe 1898) and the Iroquois traditionally ate the stalks in the spring (Parker 1910 in Native American Ethnobotany). However, Shaw’s reference to the use of Beach Pea among the Eskimo is doubtful. Following citations back from Shaw to Moerman, I finally came to Anore Jone’s research with the In͂upiaq. In her book “Nauriat Nigin͂aqtuat, Plants That We Eat,” she cites no In͂upiaq use of Beach Pea as a food and cautions against eating it. However, she does reference Euell Gibbons’ edibility claim, but suggests he is talking about a different species (Jones 1983, pg. 141).

Discussion
As an ethnobotanist, I trust the cultural traditions that have evolved through careful observation and stewardship of specific plants, landscapes, and watersheds for thousands of years. With very few exceptions, the plants that were traditionally relished by Indigenous cultures, I enjoy eating, and those considered poisonous, are substantiated by chemical analysis. But what am I to do when a plant was ignored?

A Beach Pea vine on coarse sand

The cultural cold shoulder of edible organisms isn’t without precedence among Indigenous societies in the Pacific Northwest. Tasty mushrooms like chanterelles, morels, boletes, and virtually every other edible fungi in our region were traditionally eschewed as food. Some theorize that mushrooms were avoided because of the danger of accidentally eating a poisonous one, but analogous dangers can be found in the plant world. Two members of the carrot family present a poignant case in point. The roots of Water Parsnip (Sium suave) were traditionally eaten, yet the plants look very similar to deadly poisonous Water Hemlock (Cicuta douglasii). Similarly, grains were almost universally avoided in the traditional cuisine. The closest things to grains that were eaten in this region are hazelnuts, acorns, and pine-nuts. 

Very young Beach Pea pods

We are left with a number of possible directions for exploring why the ethnographic record of Beach Pea is so scarce in this region. Was Beach Pea ignored because it produces seeds, and cultural groups along the Northwest Coast were typically not a seed-eaters (as I suggested above)? Was it ignored because it is mildly toxic, or not very tasty (as others have suggested and Hank Shaw disputes)? Or was it actually used, but of such minor importance that it suffered an early death to the forces of colonialism (like many root vegetables)? But what if Beach Pea isn’t actually native to the Pacific Northwest? Indulge me as I explore the antiquity of Beach Peas in our region.

Nearly every taxonomic authority in the Pacific Northwest assumes Beach Pea to be native to the West Coast but they have all drawn from the limited and haphazard nature of herbarium data. In fact, the first wave of botanists to explore the region did not observe Beach Pea. Archibald Menzies, the naturalist aboard Captain Vancouver’s ship, did not note the plant during his extensive travels through the Puget Sound, around Vancouver Island, and further northward along the Coast in the 1790s (Newcombe 1923). Similarly, Lewis and Clark, who spent a considerable amount of time on the Pacific Coast making salt during the winter of 1805-06, made no mention or collection of Beach Pea (Moulton 1999). The first possible written records come from David Douglas (1914, pgs 139 and 282) in 1825 and 1827, and these are a little problematic as he just labels them “Lathyrus sp.” and mentions “thick rhizomes that were eaten by the Natives,” which doesn’t quite fit this plant and is almost certainly Lathyrus littoralis. It wasn’t until 1854 or 1855 that the ethnographer George Gibbs noted the plant (Suckley and Cooper 1860), and the last quarter of the 19^th Century that botanists such as Howell, Suksdorf, and Piper made collections of Beach Pea (WTU Herbarium). We can’t conclusively say if it was absent prior to 1850, but there is certainly room for speculation.

A Beach Pea vine on gravel

Indigenous societies in the region are in a much better position than roving botanists to observe changes in plant communities. Their cultural traditions are strongly rooted in place and tied to the environment, and have been for countless generation. My experience with elders such as my mentor Clan Chief Kwaxsistalla (Adam Dick) has given me respect for both the depth and breadth of Traditional Ecological Knowledge. Not only can Kwaxsistalla identify in two languages the fish, wildlife, and plants of his homeland, but he also knows their life histories, anatomies, and habitat preferences through personal experience and cultural teachings. His knowledge is certainly better than any foreign naturalist ever could hope to acquire over the course of a short expedition.

Probing these sorts of deeply embedded ethnographic sources does hint at answers to our question. Nancy Turner, in her work with the Hesquiat noted that her consultants only began seeing Beach Peas in relatively recent times. They noticed that it came to their beaches on driftwood from logging operations. Furthermore, the naming pattern of Beach Pea in aboriginal languages is consistent with newly introduced plants. Recently arrived plants are often given “cognate” or names that are related to plants that they look like or are used in a similar way. Using English examples, early settlers called many of the root vegetables that were used by Native Americans “Indian potato” because the use and appearance of the vegetable was similar to that of the potato. In the case of Beach Pea (and in some cases also garden pea), it was given the same name as Giant Vetch (Vicia gigantea) by the Haida (Turner 2010), Dididaht (Turner et. al 1983) and Hesquiat (Turner and Efrat 1982). Perhaps the Hesquiats’ observation is true for our entire region and Beach Pea is not actually native to Pacific Northwest, but introduced early in the historic period.

Whatever the case, I aim to continue experimenting with Beach Peas wherever I find them.

Bibliography

Anonymous, date unknown. “I Eat My Peas with Honey,” a poem. http://www.poetryfoundation.org/poem/171639

 

Batchelor, John and Kingo Miyabe 1898. Ainu economic plants. Transactions of the Asiatic Society of Japan, Vol. 21, R. Meiklejohn & Co., Yokohama. http://books.google.com/books?id=RrYUAAAAYAAJ&pg=PA199&lpg=PA199&dq=Ainu+economic+plants&source=bl&ots=eaq5NIZpew&sig=jOQj2AhJWckns8u11ZHTA_kiOuY&hl=en&sa=X&ei=IR7IU4rrJ4-IogThyIKYCw&ved=0CFgQ6AEwCg#v=onepage&q=Lathyrus&f=false

Douglas, David 1914. Journal Kept by David Douglas during his travels in North America 1823-1827. Royal Horticultural Society, William Welsey & Son, London. 

Gibbons, Euell 1964. Stalking the Blue-eyed Scallop. David McKay Company Inc., New York.

Jones, Anore 1983. Nauriat Nigin͂aqtuat, The Plant That We Eat. Traditional Nutrition Project, Maniilaq Association, Kotzebue AK.

Moulton, Gary E. 1999. The Journals of the Lewis and Clark Expedition, Volume 12, Herbarium of the Lewis and Clark Expedition.” University of Nebraska Press. 

Newcombe, Charles ed. 1923. Menzies’ Journal of Vancouver’s Voyage, April to October 1792. Archives of British Columbia, Memoir No. V. Victoria BC.

Ohtsuki, Tatsuo, Yuko Kaneko, and Hiroaki Setuguchi 2011.  Isolated history of the coastal plant Lathyrus japonicus (Leguminosae) in Lake Biwa, and ancient freshwater lake. AoB Plants http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3176521/

Suckley, Goerge and James Graham Cooper 1860. "The Natural History of Washington Territory and Oregon, with much relating to Minnesota, Nebraska, Kansas, Utah, and California, being those parts of the final reports on the Survey of the Northern Pacific Railroad Route, relating to the Natural History of the Regions Explored, with Full Catalogues and Descriptions. Bailliere Brothers, New York 

Turner, Nancy J. 2010. Plants of Haida Gwai. Sononis Press, Winlaw BC.

Turner, Nancy J. and Marcus Bell 1973. The Ethnobotany of the Southern Kwakiutl Indians of British Columbia. Economic Botany 81(2):283-293.

Turner, Nancy J. and Barbara S. Efrat 1982. Ethnobotany of the Hesquiat Indians of Vancouver Island. Cultural Recorvery Paper No. 2, British Columbia Provincial Museum, Victoria BC.

Turner, Nancy J. John Thomas, B.F. Carlson, and R.T. Ogilvie 1983. Ethnobotany of the Nitinaht Indians of Vancouver Island. Occasional Paper No. 23, British Columbia Provincial Museum, Victoria BC.

WTU Herbarium. Internet search of the WTU Herbarium located at the University of Washington, Burke Museum. http://www.burkemuseum.org/herbarium