Chloe Boone
Eryngium alpinum is a hemicryptophyte, its overwintering buds are situated just below the soil surface and the floral axis more or less erect with a few leaves. The roots are deep and robust.
The stems are solitary and erect, usually with three branches on the apex and with longitudinal purple stripes. This plant generally reaches about 30–70 centimetres (12–28 in) in height, with a maximum of 100 centimetres (39 in). The basal leaves are oval or heart-shaped, 10–15 centimetres (3.9–5.9 in) wide and 13–17 centimetres (5.1–6.7 in) long, with toothed hedges and a long petiole. The cauline leaves are sessile and progressively more divided.[
The inflorescences are dense umbels at the top of the main branches. They are bright green at the bases and the stiff, bristly bracts are blue. They are about 4 cm long and 2 cm diameter and the bracts are up to 25 centimetres (9.8 in) long. The flowers inside are about 2 mm long. The peripheral flowers are sterile and the internal flowers are hermaphroditic. Both types are actinomorphic and pentamerous, with five petals. Flowering occurs in July through September. The flowers are -insect-pollinated. The fruit is a spiny achene about half a centimeter wide.
The stems are solitary and erect, usually with three branches on the apex and with longitudinal purple stripes. This plant generally reaches about 30–70 centimetres (12–28 in) in height, with a maximum of 100 centimetres (39 in). The basal leaves are oval or heart-shaped, 10–15 centimetres (3.9–5.9 in) wide and 13–17 centimetres (5.1–6.7 in) long, with toothed hedges and a long petiole. The cauline leaves are sessile and progressively more divided.[
The inflorescences are dense umbels at the top of the main branches. They are bright green at the bases and the stiff, bristly bracts are blue. They are about 4 cm long and 2 cm diameter and the bracts are up to 25 centimetres (9.8 in) long. The flowers inside are about 2 mm long. The peripheral flowers are sterile and the internal flowers are hermaphroditic. Both types are actinomorphic and pentamerous, with five petals. Flowering occurs in July through September. The flowers are -insect-pollinated. The fruit is a spiny achene about half a centimeter wide.
