and Korea, the bracken fern Pteridium
aequilinum, has been found to contain a potent
DNA-damaging chemical (p. 259). It should
be avoided. Stalks of the ostrich fern, various
species of Matteuccia, are thought to be safer
to eat.
Rhubarb Rhubarb, the leaf stalks of a large
perennial herb, is unusual for containing a
high concentration of oxalic acid. Its main use
in the West is as a tart stand-in for fruit, so I
describe it in the next chapter (p. 367).
Sea Beans Sea beans are the small, fleshy
stems and branches of salt-tolerant and salty
seacoast plants in the genus Salicornia, which
is in the beet family. They are known under
many other names, including samphire (a
name they share with a seacoast plant in the
carrot family), glasswort, pick-leweed, and
poussepierre. Young plants are crisp and
tender and can be eaten raw or briefly
blanched for their fresh, briny flavor; older