pronounced: VY-teks try-FOH-lee-uh
Vitex was the Roman name for the Chaste Tree, now known botanically as Vitex agnus-castus; trifolia means 3-leafed. The actual Latin word vitex came from vitilis, made by plaiting; the flexible branches of the Chaste Tree being used for plaiting wattle fences, much the same as willow branches are still used today.
This is a large coastal shrub or small tree, less than 5 m high, with the stems covered in small hairs. The trifoliate leaves are oppositely arranged along the stems and are usually compound, composed of 3 linear leaflets, with entire margins, anything up to 12 cm long, with the terminal leaflet usually the largest. Sometimes only one leaflet is present. The upper surface of the leaves is green, and the lower surface greyish green.
The flowers are borne in panicles up to 18 cm in length. Individual flowers have purple to violet 2-lipped corollas that are approximately 5 mm long. The stamens are in 2 pairs, and the ovary is superior, developing above the corolla. Coastal Vitex flowers throughout the year, but most prolifically in spring and summer.
The fleshy fruits are about 6 mm in diameter, turning yellowish red and finally blue or black, and contain 4 small seeds.
This plant is naturally found along coastlines from tropical East Africa as far east as French Polynesia. It grows right along the Queensland coastline, and down into Northern NSW as far south as Ballina. When it grows on exposed coastal dunes, it is usually a low sprawling shrub. In protected situations it has a more erect habit and grows taller. It has sprawling, radiating stems that are often covered by wind-blown sand. The stems produce adventitious roots at nodes along their length, and this helps the plant to bind the sand. The shrub also produces short, erect flowering branches at nodes along the stem.
This plant can withstand a moderate amount of salt spray and wind blast, but usually grows best behind the crest of the frontal dunes, where it can form dense stands. It can also tolerate partial burial under wind-blown sand, and plants have been found growing on dunes with only the upright flowering branches showing above the sand surface. It is a useful secondary sand-stabilizing species.
The leaves are used in the Cook Islands to treat female ailments, and also used to relieve fever in Samoa. In the latter country, they also burn the dried leaves to deter mosquitos.
