sward, it is important to quickly determine the cause of the problem and implement the most appropriate controls.
Dr. Kate Entwhistle asks
What’s your PROBLEM?
ALTHOUGH the cause of the symptoms is not always that easy to determine, the knowledge that you have regarding
recent management of the turf, and the way in which the problem has developed, is crucial to getting the correct result. On the turf, it is possible to identify the presence of a fungus that has the potential to cause disease but which is not causing a problem at the time of the analysis. Similarly, you may find the larvae of invertebrate pests in the turf but, if present in very small numbers, they too may not be damaging the sward. If the presence alone of a potential pathogen or pest is not sufficient to identify the cause of damaging symptoms, what is? To correctly identify the cause of any damage or discolouration to the turf, it is necessary
to understand (1) how the symptoms of the current problem have developed over time, (2) what products, if any, have been applied to the turf (or surrounding areas) in the days prior to symptom expression, (3) the relative location of the developing symptoms and (4) the possible presence of a pathogen or pest.
1. Symptom development over time
Many turf problems start with a slight yellowing to the sward which may progress to a more apparent yellowing (e.g. superficial basidiomycetes), develop through yellow to orange and red leaf discolouration (e.g. basal rot anthracnose), go from slight chlorosis through to brown, decaying turf (e.g. Microdochium patch) or result in areas of straw-coloured plants that can readily be pulled from the sward (e.g. leatherjackets or chafers).
In general, fungi that cause foliar disease will cause either a water soaking (wet, translucence) of the leaf, which occurs as the internal structure of the leaf is broken down, lesions or spots to develop along the leaf itself or a general
When something adversely affects the turf, producing unacceptable symptoms that develop on the
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