Ivy Broomrape

Appearance

Its yellowish to purplish stems are usually strongly swollen at the base and 15–60 cm by 0.3–0.8 cm. They are covered in short soft glandular hairs. Leaves are acute and oblong to lance-shaped. It's calyx are 10–15 mm with free segments that are entire or unequally bifid.

Its dull-cream to reddish purple corolla is 10–22 mm. They are almost hairless and upright spreading to more or less patent. Filaments are inserted 3–4 mm above the base of the corolla. They are usually hairless but rarely somewhat hairy below. Fruit are 10–12 mm capsules.

In Mediterranean climates it flowers from late April to mid July.

Naming

"Orobanche" is derived from Greek, and means 'bitter vetch strangler'. This name originates from the species "Orobanche rapum-genistae", which parasitizes legumes. The name "hederae" means 'of ivy', in reference to its host plant, "Hedera".

Common names in English include ivy broomrape and chokeweed. It is also called "erva-toira da hera" in Portuguese and "orobanche du lierre" in French.

Distribution

Its native distribution matches that of its host, ivy, so it is mainly found in central and Northern Europe.

In the US, the only place it's been observed is in a patch of ivy at the University of California, Berkeley. It's speculated that a botany student purposely planted it there since ivy is very invasive in California.