At this time of the year Leonard does as lot of grumbling about the noxious weeds that spread onto our property from neighboring fields and pastures. A large number of the invaders are native to the Mediterranean, arriving with the earliest explorers and mission builders and continuing even today escaping from ornamental gardens. North America is not the only continent to suffer with naturalized, unwanted, alien plants. We also “export” our share of native species that then become weeds in other parts of the world. I found a good example of a native North American flower invading an empty lot in Sakaide, Kagawa Japan.
Panicled tick clover (Desmodium paniculatum) is native to Eastern United States and Eastern Canada. This member of the Legume or Pea Family (Fabaceae) has spread into many countries where it is now considered a noxious weed. A perennial, panicled tick clover arises from an elongated caudex (root stock) with fibrous roots. The stems are not hairy and are spreading.
The compound, alternate leaves occur at intervals along the stems and have three leaflets and a long petiole (stalk) with a tiny, deciduous stipule at the base. Each leaflet has entire edges, tapers to a blunt point and extends horizonally to the ground. . Panicled tick clover leaves are not hairy, but the undersides may have very minute hairs.
The upper stems of panicled tick clover terminate in an inflorescence composed of pink to purple flowers. The flowers are pea-like with five petals and a single-styled ovary. The ten stamens are hidden.
Panicled tick clover fruits are legumes with constrictions forming 2 to 6 segments. The fruits are covered with small hooked hairs. Each fruit segment, more rounded at the bottom than the top, contains one seed and breaks apart at the constriction, but does not split open when dry.
Panicled tick clover inhabits forests and woodlands, abandoned fields, roadsides and other disturbed areas with sandy to rocky soil.
Although it is considered a weed, panicled tick clover can be a good source of fodder for deer and other hoofed mammals. Its seeds are eaten by upland game birds and small rodents. Bees visit the flowers for pollen and other insects, especially caterpillars, eat the leaves, flowers and seeds.
Tree clover, beggar lice and hitch hikers are other colloquial names for D Paniculatum.