Identifying Grass Weeds Stem/culm Node Leaf Sheath Collar Blade Midrib
Vernation Vernation is a term used to describe how the youngest grass leaves are arranged in the shoot Folded vernation Leaves that are folded in the shoot and appear V- shaped in shoots that are cut in half across the width (cross-sectioned) Rolled vernation Leaves are circular or “rolled" in the shoot and do not have folds Determining vernation: Roll test Cross-section
Ligules and Auricles Ligules are membranous or hairy tissues located at the junction of the leaf blade and leaf sheath Ligules can be membranous, a fringe of hairs, or absent Auricles are slender extensions of the collar and are located at the junction of the leaf blade and leaf sheath Auricles can be long and clasp around the stem or shoot, small or rudimentary, or absent
Growth habit and inflorescence (seed head) PanicleSpike Raceme Rhizomatous Bunch Stoloniferous
Green foxtail Scientific name: Setaria viridis Family: Poaceae Life cycle: Annual Where found: Cropland Physical description: Seed: 1-2 mm, pale lemma covering seed Seedling blade: broad and arched Leaf blades mostly hairless Vernation: round Ligule: hairy Inflorescence: compact panicle Fibrous root system Interesting facts: Latin name describes inflorescence Seta =bristle, viridis =green Also called green bristlegrass
Jointed goatgrass Scientific name: Aegilops cyclindra Family: Poaceae Life cycle: Annual Where found: Cropland Physical description: Seed: attaches firmly to lemma and palea at each joint Seedling blade: first blade tall, narrow and vertical Leaf blades with long hairs on margins of blade and collar Vernation: round Ligule: membranous with toothed margin Inflorescence: columnar spikelet with distinctive joints Fibrous root system Interesting facts: May behave as a winter annual in some areas Known to hybridize with wheat
Quackgrass Scientific name: Agropyron repens ( aka Elytrigia repens) Family: Poaceae Life cycle: Perennial Where found: Range, Cropland Physical description: Seed: resemble wheat; slender, elongate, tan Seedling blade: first blade tall, narrow and vertical Leaf blades mostly hairless, often constricted at the tip Vernation: round Ligule: short, membranous Clasping auricle Inflorescence: spike Aggressive, rhizomatous root system Interesting facts: Latin name describes resemblance to wheat and creeping root systems Agropyron =wild wheat; repens =creeping Also called couchgrass
Wild oat Scientific name: Avena fatua Family: Poaceae Life cycle: Annual Where found: Cropland Physical description: Seed: long with twisted awn attached to lemma Seedling blade: first blade tall, narrow, vertical Older leaf blades have long hairs on margins of blade and collar; stems nearly hairless Vernation: round Ligule: membranous, tall, slightly toothed Inflorescence: open panicle with drooping spikelets Fibrous root system Interesting facts: Awn helps plants twist into the soil Twisted when dry, straightens when wet Plant may grow 4 feet tall