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DescriptionThis adventive or introduced annual plant is 1-3' tall, branching frequently and often having a bushy appearance. The round stems are initially dull green, but become light brown with age. Young stems have abundant white hairs, while older stems become more glabrous with age. The alternate leaves are up to 3½" long and 1" across. They are ovate or obovate, glabrous, smooth along the margins, and sessile or nearly so. The upper surface of the leaves often has a white margin of varying width; this white margin has a tendency to become broader and more conspicuous as the leaves approach the flowers. The leaves (or leafy bracts) immediately below the flowers are smaller in size and often opposite or whorled, otherwise they are similar to the other leaves. As a plant matures, there is a tendency for the lower leaves to turn yellow and fall off the stems, particularly during dry weather. The upper stems terminate in small clusters of flowers. The structure of these flowers is typical of members in the Spurge family, although their size is larger than average. Both the male and female flowers develop within a cyathium, which is about ¼" long and shaped like a cup. This cyathium is covered with white hairs on the outside and has 5 glandular appendages along its rim at the top. Each petal-like appendage is white and more broad than long. The male flowers are without sepals or petals, consisting of stamens with anthers that are not exerted significantly from the cyathium. Each female flower is without sepals or petals, consisting of a 3-valved pistil with 3 divided styles. The pistil of the female flower is about 1/3" across and is strongly exerted from the cyathium from a short stalk that is either nodding or erect. Like the cyathium, the pistil is covered with white hairs, and its valves are well-rounded. The blooming period occurs from mid-summer to early fall and lasts about 2-3 months. There is no noticeable floral scent. Both the cyathia and male flowers wither away, while each female flower becomes a 3-celled seed capsule. Each of these cells contains a single seed. The seeds are oval in shape, and their surface is reticulate and rather bumpy (tuberculate). They can be flung several feet from the mother plant by mechanical ejection. The root system consists of a stout taproot. This plant spreads by reseeding itself.