Bidens alba
Bidens alba, which belongs to the family Asteraceae, is most commonly known as shepherd's needles, beggarticks, Spanish needles or butterfly needles. "Bidens" means two- toothed, describing the two projections found at the top of the seeds, and "alba" refers to the white ray florets. This plant is found in tropical and subtropical regions of North America, Asia, South America, and Africa, situated in gardens, road sides, farm fields and disturbed sites. "B. alba" is an annual or short-lived perennial, which is considered a weed in the United States. However, "B. alba" leaves are edible and can  be used as medicinal remedies. Description. "Bidens alba" is a vascular plant. It has a similar root and stem system to others in the dicot family "Asteraceae". After germinating, the roots progress into a tap root that grows vertically in the ground. The primary tissue of the apical meristems increases the length of the plant and the secondary roots of the lateral meristems give rise to the width. "B. alba" grows to a height of approximately five feet. The stem of "B. alba" plant emerges from the taproot, yet the bent stem at the base also has the ability to  grow into roots at the lower nodes. Stems are mostly hairless and green to purplish in color. The vascular bundle provides nutrients throughout the plant, with the xylem transporting water from the roots and the phloem obtaining food from the leaves. "Bidens alba" leaves, which are simple on the opposite side and compound on the underneath, are long and wide. The underside leaf is hairy, and has toothed edges. The leaves may be lobed, depending on the species. Some have teeth and some do not; each node produces two leaves along the stem. Each flowering head of "B. alba", which  is small, appears in radial symmetry. The flowers on this plant are depicted as daisy-like due to the larger white petals and the very small yellow flowers which are located at the end of the branches. Colors of the flower-heads of "Bidens alba" vary depending on the subspecies; some "B. alba" have yellow, tubular central blossoms and others may have flower-heads with white or cream petals ( long); eventually they form black linear seeds, yielding approximately 1200 seeds per plant. Cultivation. "Bidens alba" is a fast-growing, fast-spreading weed due to its enormous number of seeds and  the ability to re-grow from stems. In sub-tropical to tropical conditions, "B. alba" can grow almost everywhere in full sun with little or no moisture. The most growth occurs in organic matter with loose soil; however, they can also propagate well on sand and lime-rocks in non-irrigated habitats. The seeds are dispersed mainly by animals or humans, although some are also carried by wind and water. Uses. "Bidens alba" provide a nectar source for butterflies and honey-bees. Bidens is a nutrient dense wild plant, boasting a similar nutrient profile to kale - high in fiber and  proteins, carotenes, folate, and magnesium. People in South Africa, Zulus, and Indians consume the fresh or dried leaves by boiling them. Young leaves of "B. alba" may also be eaten as a salad. "Bidens alba" contains saponins, so older leaves may be unpleasant to the taste and may upset the stomach. A list of claimed medicinal actions include “antibacterial, antidiabetic, antidysenteric, anti-inflammatory, antimalarial, antimicrobial, antiseptic, astringent, blood tonic, carminative, galactagogue, hepatoprotective, hypoglycemic, hypotensive, immunomodulant, mucous membrane tonic, neuroprotectant, prostaglandin synthesis inhibitor, styptic, vulnerary”. Bidens is considered by some as a broad spectrum antimicrobial, useful particularly against infections that are  inflammatory to the mucous membranes. A poultice of leaves can be used topically to treat MRSA and other infections of the skin. Research has shown that the antimicrobial properties are best accessed through the fresh plant or alcohol tinctures of the fresh plant. The dried leaves of the B. Alba also make a good tobacco substitute.