This is what grass would look like under the microscope if Wimbledon didn’t take place. The slit-like structures are called stomate. They are miniature mouths that cover the entire grass blade and let in carbon dioxide – the gas from which new plant matter is made.
In hot or dry conditions, plants close their stomate in order to preserve moisture. But this also means a halt in growth. The head groundsman’s job is to make sure, this doesn’t happen by keeping the lawn moist, fertilized, and well aired. Because if the grass shuts up, Wimbledon shuts down.