Poaceae (poh-AY-see-ee)
Iconic Features
- Hollow stems
- Usually narrow, sheathing leaves
- Small, petalless, pale flowers
- Fruit a grain
Description (Jepson)
- Annuals or herbaceous perennials
- Monocotyledons (monocots) – monocots are a major lineage of flowering, mostly herbaceous plants, generally characterized by
- Single seed leaf (cotyledon)
- Linear or oblong leaves with parallel venation
- Flower parts in threes
- Pollen grains with a single pore
- Vascular bundles scattered in stem
- Fibrous root system
- Leaves
- Usually narrow leaves sheathing the stem
- Sheaths usually with a small appendage called a ligule
- Alternate (1 leaf at each junction with stem)
- Flowers
- Small, generally bisexual, petalless flowers in spikelets
- Wind pollinated
- Fruit a grain (a dry, one-seeded fruit with a fused seed coat)
Notes
- Approximately 10,550 species worldwide
- Includes wild and cultivated species of wheat, rice, corn, rye, fescue, brome, oats, barley, and bamboo
- Greatest economic importance of any plant family
- Grasses, oaks, and silk tassels are examples of plants at Edgewood that are wind pollinated
- About 12% of flowering plants and most conifers are wind-pollinated (US Forest Service)
- These plants do not waste energy on flower features that attract animal pollinators; instead, their flowers generally have these characteristics
- Minute, inconspicuous, petalless flowers
- No nectar
- Stamen (male flower part) and stigma (pollen receiving structure of female flower part) are exposed to air currents
- Male flowers produce a great deal of pollen, which is very small, dry, and easily airborne, as all allergy sufferers know!
- Scientific name from the included genus Poa, from the Greek for “fodder”
- Represented by 56 species at Edgewood
Specific References
Abrams, L.R. and Ferris, R.S. 1940-1960. Illustrations. Illustrated Flora of the Pacific States, Washington, Oregon and California (IFPS). Four volumes. Stanford University Press, Stanford, California. Public Domain.
US Forest Service. Celebrating Flowers: Wind and Water Pollination. United States Department of Agriculture.
