Viscum album, the only native British mistletoe, is rich in associated folklore, and commercially important for the Christmas markets and its
medicinal uses. Like all mistletoes, it is a hemiparasite, photosynthetic, and attached only to the host xylem, initial contact with which stimulates hypertrophy of the host tissue. It is hence a gallcauser, inducing variable but often marked and conspicuous swelling of the host.
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