Integrated Pest Management
Large Crabgrass
Digitaria sanguinalis
Large crabgrass growth habit (Doug Doohan, The Ohio State University, Bugwood.org)
Large crabgrass (Steve Dewey, Utah State University, Bugwood.org)
Description
- clumping grass with horizontal growth (when mowed) or upward growth up to 2 feet tall (when un-mowed)
- coarse and hairy leaf blades commonly tinged with purple; ligule is very short, jagged and membranous
- flowers and seeds are produced on whorled spikes (2 to 16 spikes per stalk) and are 2 – 6 inches long
Location
- commonly grows in lawn areas and planting beds
Life Cycle
- summer annual, warm season grass; seedlings germinate when temperatures reach 55°F and continue to germinate throughout the growing season
- flowers and seeds appear from mid-summer to first frost
IPM Recommendations
- Hand-pull plants in planting beds prior to seed maturation.\
- Effective control must target both aboveground and underground plant structures; manually remove underground structures to prevent re-sprouting.
- Shallow tillage or hoeing will control young plants in planting beds. Do not till established plants; root fragments will produce new plants.
- Apply an appropriate post-emergent herbicide directly to target weeds.