Scientific name: Blackstonia perfoliata (L.) Huds.
Common name: Yellow-wort
Description
Habit: A hairless annual, to 50 cm high.
Stems: Erect, sparingly branched.
Leaves: Undivided, pale bluish green, entire, oval, opposite and united at the base.
Flowers: Yellow, actinomorphic, hermaphrodite, 15 mm across; calyx fused, deeply divided with 8 linear lobes; corolla fused with 8 spreading lobes, tube shorter than lobes; stamens attached to the corolla and alternate with the corolla lobes; ovary superior.
Fruits: A globular capsule.
Habitat: Dry grassland, sand-dunes, limestone pavement, stony places.Distribution: Wide distribution on limestone, very rare elsewhere.
Native status: Native
Of conservation interest: No