Biologicals and fungicide use

I love off the cuff marketing statements such as “the turf management
practice that does most damage to soil microbes, is synthetic fertilisation”.

When it’s taken into account that statements such as these are often made by companies that are promoting their own range of biologically enhanced fertilisers in direct competition to these “bad boys” one does tend to be a touch cynical. These same companies also conveniently fail to mention the
impact of fungicides that they supply on soil microbial populations. But why let that get in the way of a good story!

A USGA spec golf green for example, is not a natural environment and in reality it can be best described as a hydroponic medium which supports turfgrass roots. The key aim, of growing grass whilst maintaining a freely
draining rooting medium and a firm surface, hardly mimics the requirements of for example a cereal farmer.

As a result of this, it’s a fair call to say that the demands on a sports surface differ significantly. The requirements for pesticides and other inputs can vary dramatically compared to a production system. Whilst a
farmer might use manure on a paddock this approach isn’t generally recommended on a golf green and how many farmers spray weekly as part of a management program?

If you are intending to go down the pathway of reducing synthetic inputs it can only be an all or nothing approach. You can’t simply stop using synthetic fertilisers and switch to biological inputs and expect the same results if you carry on with your usual practices such as fungicide applications.

There’s a good chance that any fungicide applied will kill the microbial “goodies” such as VAM or trichoderma you are trying to encourage. Sort of defeats the purpose really.

There appears to have been very little work done on using biological products in intensively managed turf situations, with the majority of trial work tends to have been carried out in isolation of other inputs which is hardly a realistic scenario. Factors such as irrigation regime, pesticide inputs and even wear are seldom taken into consideration, when in reality we all know these can play a dramatic role on how a surface performs.

With the drive to reduce inputs many golf course superintendents are for example using annual N levels of less than 1kg/100m2 already which hardly constitutes massive amounts of fertiliser in anyones book.

In the case of pesticide use, fungicides dominate. For example triazole fungicides including propiconazole, tebuconazole, tetraconazole, triadimenol, triadimefon, and triticonazole show toxicity to a wide range of
non target organisms. I would be intrigued to know how many turf managers go down the biological route but continue to use these as they are cheap with no thought to their impacts on the biologicals they are trying to promote?