I had the pleasure today of visiting Headingly and meeting Ryan Golding the Head Groundsman at the Emerald Headingly. They are in the process of extending their stadium and the newly extended South stand is begining to cast a rather large shadow.

In the shaded area under the South Stand they on a bright February day (probably record breaking again) the turf is receiving about 120 micromoles of PAR light.

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In full sun they are receiving about 750 to 900 Micromoles of PAR light. So in this stadium environment, the shading effect is around 85%. Given a good day in February can deliver around 27 DLI at best. A bright sunny day in the shaded area could deliver around 4 DLI.

The best current research I can find at this kind of height of cut Ryegrass needs around 23 DLI. So it’s falling about 19 DLI short. In these situations supplementary lighting helps fill th gaps.

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Given that supplementary light delivers around 350 micromoles of additional light at turf level that’s around 13 hours of supplementary lighting to reach the goal of 23 DLI.

The shade is also reducing canopy temperatrues by around 4 degrees and learning from my recent soil temp studies – probably reducing soil temperatues by at least 4 degrees too.

This is clearly visable in the quality of surfaces. More light + higher temperatures = better turf.

This is already presenting challenges with the clubs desire to have shorter and tighter turf to encourage a faster game but a Turf managers need to keep turf long to give the plant as much oppurtunity to photosynthesise as possible to maintain any amount of coverage.