Jerusalem Artichoke 

Flowering heads have from 10 to 20 yellow ray flowers that surround a central cluster of immature, greenish disc flowers, or mature, yellow disc flowers, or a combination of both. Leaves are are attached to the stem in pairs, except near the top, where they may occur individually. Leaves are up to 30 cm long and 10 wide, and have three prominent veins which emerge from a common point near the leaf base. Leaf margins have shallow teeth which terminate in small, sharp points, at intervals of 0.6 to 2.0 cm. The broadly lanceolate leaves have a recurved base, which narrows as it tapers down each side of the petiole to meet the stem (winged petiole). The upper surface of the leaf is sandpaper-like. The stem is rough. Found in woods and woodland edges from August through October. Helianthus tuberosus differs from H. strumosus in having larger leaves, and rough, rather than smooth, stems. Two forms of H. tuberosus exist: a larger form, usually 2.0 meters or more in height, and a smaller form, having a height of about l.0 meter. Both forms appear to be present at Saylorville Lake. Native to N. A.