Pickleweed

Pickleweed is a name applied to several plants in the genera Salicornia and Arthrocnemum. Our most common pickleweed (S. pacifica), also called Pacific swampfire or glasswort, is a low growing, succulent plant that dominates the mid-elevations of the salt marsh. Throughout the summer, its low, bright-green appearance gives the marsh a golf-course-like appearance. By autumn, most pickleweeds are more red than green.

More than 100 years ago, Parsons ³⁹⁹ wrote “Though a humble enough plant in itself, the samphire, or glasswort, is the source of a wonderful glory in our marshes in the autumn. Great stretches of tide-land . . . are covered by it, showing the most gorgeous blendings of crimson, purple, olives and bronzes,which. seen with all the added charm of shifting and changing atmospheric effects, far outrival any Oriental rug . . . ”

Description ^2,4,59

Pickleweed is a low-growing, succulent, perennial subshrub. The main stems are horizontal, the lateral stems vertical, generally less than 3 feet (1 m) in height. Stems appear jointed, joints are barrel shaped, usually less than 3/8 inch (1 cm) in length; the lower, older joints are larger. The senescent portions of stems turn rose-red, especially in late summer and fall. Plants may go dormant and turn brown in the winter.

Leaves are reduced to scale-like structures clasping the stems.

Flowers on a pickleweed are small and inconspicuous, mostly concealed in the fleshy tissue of the node. Most obvious are the stamens and pistil that look like small flecks of dandruff. These are are greenish-white and arise from junctions between stem segments. At each junction, there are two clusters of three flowers, each contiguous in a horizontal line. Each flower has two stamens and one pistil. Flowers appear July – November.¹ They are wind pollinated.

There is one tiny seed per flower, about 1/16 inch (1-1.5 mm) in length.

Classification  

Pickleweed is a dicot angiosperm in the goosefoot family, Chenopodiaceae.² Plants in this family are often succulent or scaley; many appear weedy; many are salt tolerant. Typical flowers are tiny, greenish and lack petals.^11,34,44

Well known members of the goosefoot family include beets and spinach.

Familiar goosefoot species in the Reserve include the large shrub, Brewer’s saltbush (Atriplex lentiformis ssp. breweri) and  fat hen (A. prostrata), which helps pickleweed give the marsh its reddish fall color.

There is one other species of Salicornia in the Reserve: the annual slender glasswort (S. depressa).⁴⁸  A similar but somewhat shrubbier species is also found; this was recently moved into a different genus and the current scientific name is Arthrocnemum subterminale.

Until recently, S. pacifica was considered conspecific with S. virginica, the common pickleweed in the east.²

Ecology  

Like other saltmarsh plants, pickleweed has special adaptations that allow it to use seawater as a primary source of water. Pickleweed is an “accumulator”. As saltwater is taken up, the salt is removed and stored as concentrated brine solution in special chambers (vacuoles) in the terminal segments. As vacuoles become full of brine, that segment become red and drops off the plant, removing the salt.^31,174

Salt accumulation involves internal storage of water like cactus and other plants of arid regions. Thus, salt accumulators, including pickleweed, generally have a succulent appearance.³¹

Although pickleweed can withstand short periods of flooding, it will die under prolonged immersion – as when the estuary mouth closes and the salt marsh floods. The natural circulation cycle of San Elijo Lagoon included such periods of flooding. Unfortunately, with the encroachment of houses and transportation corridors, the natural circulation cycle no longer operates. To avoid stagnation, Nature Collective has attempted to maintain an open channel to the ocean since 1996. This has reduced the frequency of flooding in Central Basin, and during that time the pickleweed has increased dramatically. Unfortunately, this has occurred at the expense of our tidal mudflats, which are important habitats for shorebirds.

Human Uses  

Kumeyaay chewed the raw stalks for salt.¹⁶

In parts of Europe, pickleweed has a long history as a food plant. The British call the stalks “sea beans”, “sea asparagus” or “sampire”. Sea beans are eaten raw (e.g. in salads), pickled or cooked as a vegetable.^28,29

In the 18th century, pickleweed was a source of soda ash for early glass making, which is why species in this genus are sometimes called “glasswort”.⁴¹

An atmospheric physicist is experimenting with seawater-based Salicornia farms in Mexico. Crops may be used for food and for biofuel, and may eventually help combat climate change.³⁰

Interesting Facts  

Pickleweed (S. pacifica) is the preferred habitat for the endangered Belding’s Savannah Sparrow, which feeds and nests in pickleweed.^34,40

Pickleweed is one of the hosts of the saltmarsh dodder (Cuscuta pacifica), which parasitizes pickleweed during the summer. The dodder is an annual plant and pickleweed is perennial. Thus, unless the dodder is extremely abundant, chances are good that any one pickleweed will be parasitized for a single year only, giving it time to recover during the following year.