Lythraceae, the Loosestrife Family
Herbs or shrubs, with opposite or alternate entire leaves; receptacle cup-shape or tubular, bearing the 5-7 petals and sepals at its margin, and the 6-12 stamens on its inner surface; ovary superior.
| 1a. Stem shrubby (aquatic, stems 1-3 m. long; flowers pink, summer) | Water Loosestrife, Decodon verticillatus. |
| 1b. Stem herbaceous (4-10 dm. high; flowers purple, summer) — 2. | |
| 2a. Flowers solitary in the axils; leaves mostly alternate | Loosestrife, Lythrum alatum. |
| 2b. Flowers in terminal panicles; leaves opposite or whorled | Loosestrife, Lythrum salicaria. |