While known from the east coast of Australia, the first case of this devastating turf disease has recently been confirmed in the Northern Territory of Australia.
The area was recently sown to Buffalo turf, as sod, in several tranches, in October and November 2007. Conditions were dry [late dry season] and hot to very hot [day temperatures 33- 36C], but adequate irrigation was available and the sod established quite well, and vigorous growth commenced. Adequate slow release fertiliser had been placed under the sod, and the turf area was developing, with roots pegging the sod to the basal soil.
Typical late dry season conditions continued with intermittent storms and dry periods through to late December, with monsoonal conditions from December 27, 2007. Irrigation was used through to late December.
An urgent call in early January from the client – “my lawn is dying” and investigations began.
The lawn has been devastated, with large dead patches across almost all the site. Typical insect damage from army and sod web worm was ruled out as no active caterpillars were found, although superficially damage was similar. At this stage plant disease was suspected and investigations soon lead to the possibility of take all.
Samples were sent for analysis at the local Department of Primary Industries and Fisheries labs at Berrimah, with the disease being confirmed as Take All. Thanks to the staff there for help with confirming the diagnosis.
This is a new plant disease record for the Northern Territory.
The disease does occur on almost all turf grasses including those in the tropics, where the disease seems to be more aggressive. Buffalo grasses [ St Augustine in the USA] seems particularly susceptible.
Control is difficult, with agronomic management as important as any use of spray fungicides. In the USA, best results have come from a combination of soil and turf stolon [that material close to the soil especially] pH management, raised cutting heights, modest fertiliser rates and reduced nitrate rates [ammonium forms preferred]. All have a part to play, with the pH management most important. In essence, preventative measures rather than true control through any spray program. Early signs of yellowing were not noted, although that is a frequent early warning of the disease.
There is a lot of US material on the web worth a look. Search for “take all”, with a few university extension agencies having excellent brief technical information suitable for commercial contractors and home gardeners. More photos at: http://www.flickr.com/photos/13624018@N03/2209481592/in/set-72157603767945773/
Further work is continuing to aid the recovery of the turf. Dry, generally sunny weather from around the second week of January seems to have helped with development of new stolons, which have recolonised some areas. A spray with a fungicide known to have had some effect in slowing the disease also seems to have helped.
We can offer professional consulting services if your area is affected with this disease.