Common Knotweed
Polygonum aviculare · Warm-season, Annual, C3-C4 broadleaf weed frequently managed alongside turf
Grass Family
Polygonaceae (Note: Polygonaceae is a broad dicot family, often mistaken for turfgrass due to its sprawling weed habit in lawns)
Grass Category
Invasive/Weed Grass and Turf-infesting broadleaf weed
Variety / Cultivar
Wild type
Hardiness Zones
USDA Hardiness Zones 3 through 10
About This Grass
Forms dense, low-growing blue-green mats flat against the ground, highly tolerant of compaction and heavy foot traffic, with inconspicuous tiny white or pinkish flowers
Blade Characteristics
Leaves are alternate, elliptic to lanceolate, blue-green to grayish-green, typically 0.5 to 2 inches long with distinct silvery membranous sheaths (ocrea) at the nodes
Root System
Deep, tough, fibrous taproot system that allows survival in extremely compacted and dry soils
Growing Information
Origin Region
Europe and Asia, now widely naturalized globally in temperate and subtropical regions
Growth Habit
Prostrate, mat-forming, spreading via branching stems radiating from a central taproot
Sunlight & Water Needs
Full sun, low to moderate water needs once established, exceptionally drought tolerant due to deep taproot
Mowing & Maintenance
Grows so flat to the ground that standard mower blades often miss it entirely; controlled primarily through herbicides, hand-pulling, or alleviating soil compaction
Special Characteristics
Extreme tolerance to soil compaction, heavy foot traffic, and poor aeration; thrives where desirable turfgrass fails
Ecological Information
Introduced weed species globally; provides minimal wildlife value compared to native plants; acts as an indicator of heavy soil compaction