[null and void]

It’s not clumps of grass, it’s “clumps” of NO grass.

[Eccl 10:2]

"Analysing the spatial separation of both high- and low-vitality grasses, and using moisture sensors to check readings at the ground, the team found that healthier, high‐vitality grasses were systematically more strongly associated with fairy circles than low‐vitality grasses."