Lagarosiphon major is a perennial, submerged aquatic plant that can grow in dense mats up to 6.6-9.8 ft. (2-3 m) thick.
Foliage
The stems, which can reach the surface, are brittle and sparsely branched, 0.12-0.2 in. (3-5 mm) in diameter and curved towards the base (J-shaped). The leaves are 0.2-0.8 in. (5-20 mm) long and 0.08-0.12 in. (2-3 mm) wide, and occur in alternate spirals along the stem.
Flowers
The flowers have three petals and are very small 0.01 in. (0.25 mm) in diameter and up to 2.4 in. (6 cm) long, and clear-white to pink on the surface.
Fruit
The fruit capsule is beaked with seeds 0.13 in. (0.32 cm) long, averaging nine to a fruit. Lagarosiphon major can also reproduce by stem fragments.
Ecological Threat
Lagarosiphon major is fast-growing and may completely fill the volume of a large shallow lake up to 9.8 in. (3 m) deep. It is native to southern Africa.