Prostrate knotweed, goosegrass, and broadleaf plantain are an indicator of which turf condition?

• A. Overwatering
• B. Dry, sandy soil
• C. Compacted soil
• D. Low fertility

Answer: (C)

These weeds signal soil compaction in a turf stand. When the soil is compacted, pore spaces shrink, oxygen in the root zone drops, drainage slows, and turf roots struggle to grow deeply. Prostrate knotweed and broadleaf plantain form low, spreading mats that tolerate crusted, stressed, and drier spots, so they readily occupy areas where the turf is thinning. Goosegrass is a hardy weed that thrives under traffic-affected, compacted soils where the grass can’t compete well. The combination of these species commonly points to compacted soil rather than just low fertility or overwatering. To fix it, relieve compaction with aeration (core or solid-tine), then amend and overseed as needed to rebuild a healthier rootzone.