It’s getting hot out there

Fast Show Skorchio

Yesterday …Skorchio …. Today ….. Skorchio ….. Tomorrow …… Skorchio

For those of you too young to remember the Fast Show reference, you can catch up here.

The serious question is can turf get too much light?  We certainly don’t want shade conditions, where there is not enough light.  But yes, turf can also receive too much light.

It’s something I’ve been explaining at the recent Turf Science Lite events, when introducing new Ryder pigment technology.

There are many factors at work in the stress we are seeing, but it is highlighting one aspect researchers have been telling us, that, when there is too much light, the leaves absorb more energy than the plant can convert – via photosynthesis – into carbohydrate – and the result is the creation of high-energy free-radicals. These can bounce around inside cells and can degrade chlorophyll and damage plant membranes.

In fact, when it gets to this situation, the plant actually becomes less photosynthetically active and it is positively detrimental – the process of photo-inhibition.

The impact of light is by far most significant when turf is under stress.  This can be heat stress, cold stress, drought stress or stress due to wear or even height of cut.  Then light stress can start to kick in at relatively low light levels, and occurs almost every day at some stage. Even in winter, when the plant is naturally less active, a bright winter’s day could be causing more problems inside the cell. It is something that I’m keen to test and investigate further in the UK.

Added to too much mid-spectrum PAR light, these bright sunny conditions are bombarding the leaf with UV light too.

Golfer and turf suffer in hot sun mr

And then we have the issue of water availability – which is crucial for all the plant’s internal cell mechanisms. It’s vital to maintain cell structure, to move nutrients – required to utilise all the energy being created – and for transpiration to keep the plants cool.

What we have is a perfect storm of weather conditions that have conspired to put immense stress on the plant.

By the middle of next week, the turf specific weather forecasting on GreenCast is predicting ground temperatures in southern England at dangerous levels for turf:

GreenCast - June 2018

There’s no one instant solution – and water management is possibly the most important factor – but there is clearly an important role for Ryder in the current conditions. The key attribute here is how it will act as a sun screen to temper the PAR light overload and protect from the damaging UV radiation.

Experience in the US has consistently shown how it can help to protect plants from the effects of excessive light and to make the sunlight work more efficiently. We are in the process of getting feedback from a group of turf managers in the UK, who have seen some very positive effects, along with STRI trials.

And as turf continues to burn up, with few signs of significant rain on the horizon, there’s the big factor that Ryder will colour turf green and keep it looking attractive for players. The bonus is that, since growth has all but shut down in the intense heat and dry, the pigment won’t grow out and be mown off, so will remain looking great for longer.


Even in Scotland, at Turf Science Lite at St Andrews, I have had the light meter out on the course and it has been apparent that light is at potentially damaging levels for extended periods of the day. Once you start to analyse these things it shows that morning light is where the scientists indicate is the most beneficial for photosynthetic activity – which actually bears out what I’ve seen as a greenkeeper and reinforces the priority to clear shade from greens for the morning sun.

Light levels at their optimum around 8.30am at St Andrews


What it has also shown just how long and how late in the day light levels remain at potentially damaging levels and where Ryder could have a benefit.


Some of the comments that I’ve had from the meetings is that the light meter may just become as essential a piece of kit for turf management as a moisture meter. And that’s all to the good if we can make light work more effectively for turf health and playability.

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