Pteridophytes

Equisetaceae
Horsetail Family

• Sterile Stem: perennial; from an underground stem; 6” to 2’ tall; jointed; highly branched with whorls of branches at the stem nodes; branches 3” long, jointed; stems are green with a rough surface and with tiny ribs; sheath of tiny leaves encircling each node, with 1/16” points.
• Fertile Stem: from an underground stem; 6” to 8” tall; without branches; whitish; appearing before the sterile stems in the spring and withering within a few weeks; sheath of leaves at each node with 1/2” tips.
• Cone: at the tip of the fertile stem; 1” long by 3/16” in diameter, pointed toward the tip, drooping at maturity, light brown; producing spores from tiny capsules (sporangia) underneath the shieldlike plates of the cone; spore production is completed before mid-May.
• Habitat: common in moist to dry, open places, often with some disturbance, such as roadsides or railroad embankments; frequent on prairies; usually growing in patches.
• Bibliography from Biodiversity Heritage Library
• Vascular Plants of Iowa