Take-all patch
Gaeumannomyces root disease of bentgrass
Slow-recovering bentgrass patches need a root inspection.
Photo: Pete Dernoeden, Ph.D / Syngenta GreenCast · Full photo ↗
What to look for
- Bentgrass develops brown patches that may expand over time.
- Roots, runners and shoot bases can become dark brown or black.
- Other grasses or weeds may occupy the damaged centres.
Working with warm-season turf?
For couch, kikuyu, buffalo or paspalum, compare the separate couchgrass decline / take-all root rot guide. Check the grass species before drawing a conclusion from the patch shape.
More photos to compare
Compare the overall pattern with the plant detail. Check the grass species and growing conditions as well as the appearance.
Photo: Pete Dernoeden, Ph.D / Syngenta GreenCast · Full photo ↗
View illustrated field cues
Look closer before you treat
Photograph the whole patch, the active edge and individual plants. Include your grass variety, location and recent maintenance history.
Confirm it before you treat it
This guide concerns take-all patch in bentgrass. Similar names are used for other root diseases; do not assume that a buffalo or couch problem has the same diagnosis.
What to do next
- Compare roots from the active patch edge with healthy turf and submit a sample.
- Review drainage, soil testing and recent liming before changing fertiliser.
- Discuss repair and a diagnosis-led disease program for affected greens.
Conditions matter more than dates.
Cool wet conditions, drainage problems and elevated soil pH are useful investigation prompts. Newly established bentgrass greens can be vulnerable.
Should I acidify the soil straight away?
No. Confirm the disease and use soil-test results to guide any pH or nutrient changes.
Reviewed 11 October 2026 · Turfmate. Identification guidance is not a laboratory diagnosis or a spray calendar.
Technical sources
- Bronze and reddish-brown take-all patches in bentgrass. Photo: Pete Dernoeden, Ph.D / Syngenta GreenCast · Syngenta content licence.
- Yellowing patches in a declining take-all outbreak. Photo: Pete Dernoeden, Ph.D / Syngenta GreenCast · Syngenta content licence.
Syngenta photographs are reproduced in full with attribution. Source grass species and settings are identified where supplied; photographs support identification and do not replace diagnosis.
- Take-all patch — Photo: Take-all patch in bentgrass · Pete Dernoeden, Ph.D., via Syngenta GreenCast · Syngenta content licence. Complete photograph displayed without cropping, overlays or colour changes.