Yellow Woodsorrel
Oxalis stricta · Broadleaf Perennial (C3 photosynthesis). While not a true grass, it is a common turfgrass weed that grows in similar conditions to cool-season lawn grasses.
Grass Family
Oxalidaceae (Note: This is an herbaceous broadleaf dicot, not a member of the Poaceae/grass family)
Grass Category
Invasive/Weed. Often found in Lawns/Turf, Gardens, and Disturbed areas.
Variety / Cultivar
Common wild type; no specific ornamental cultivar is identified in this turf setting.
Hardiness Zones
USDA Zones 3-9; very hardy and capable of surviving significant frosts, though it may go dormant in extreme heat or cold.
About This Grass
A low-growing herbaceous plant that mimics clover. It features bright green, trifoliate leaves and small, five-petaled yellow flowers. It produces upright, explosive seed pods (cylindrical capsules) that disperse seeds several feet.
Blade Characteristics
Leaves are heart-shaped (obcordate) and grouped in threes (trifoliate). They lack the parallel venation of grass. Color is typically lime green to light green. Leaves fold downward at night or under stress.
Root System
Features a slender, branching taproot and/or shallow rhizomes. It is easily pulled from the soil but can regenerate from root fragments.
Growing Information
Origin Region
Native to North America; now naturalized nearly worldwide in temperate climates.
Growth Habit
Upright to prostrate herbaceous growth; spreads via seeds and sometimes short rhizomes or stolons.
Sunlight & Water Needs
Full sun to partial shade. Prefers moist, fertile soils but is highly drought-tolerant once established. High tolerance for various soil pH levels.
Mowing & Maintenance
Maintenance involves removal via selective broadleaf herbicides (containing Triclopyr or 2,4-D). Regular mowing does not kill it as it can set seed at very low heights; hand-pulling is difficult due to root fragmentation.
Special Characteristics
Contains oxalic acid which gives it a sour taste. It is highly competitive in thinned lawns and is known for 'exploding' seed pods that aid in rapid colonization.
Ecological Information
Native to North America. Provides nectar for small bees and butterflies. Often considered a weed in manicured landscapes due to its aggressive spreading and ability to outcompete turfgrass.