Equisetaceae “Horsetail Family” 1 genus and 15 species

Water Horsetail Equisetum fluviatile Leaves-whorls 4-9 mm long black-tipped scales along the stem. Stem- dark green, stem pulls apart at the joints. Hollow Flower- No flowers, but a cone-like spore-producing structure develops at the end of the fertile stems. Fruit- produces a spore instead of fruit. Root- rhizome with deep roots.

Field Horsetail Equisetum arvense Stems- Short, succulent, yellowish shoots. The stem never turns green. Root- At the base of the lateral branch buds, rhizomes and shoots. No leaves Fruit- spores not fruit

Field Horsetail

Meadow Horsetail Equisetum pratense Stems- have fertile and sterile stems. Hollow and 1-4 mm thick. Leaves- small scales fused into pale sheaths, 2 - 6 mm long, with 8 - 10 brown, white- edged teeth. Fruit- spore cones. 3-sided branches.

Woodland Horsetail Equisetum sylvaticum Stems- Die each year, hollow. Fertile- unbranched at first then compound; green with 10-18 spiny branches. Leaves- scales fused into sheaths around the stem, 3-5 brown teeth. Spore clusters- single, long-stalked, cones at fertile stem tips.

Woodland Horsetail

References http://www.ecy.wa.gov/programs/wq/plants/plantid2/descriptions/equflu.html http://www.rook.org/earl/bwca/nature/ferns/equisetumarv.html http://www.borealforest.org/ferns/fern5.htm http://www.borealforest.org/ferns/fern6.htm