Grass Material changes based on camera disteance

Probably a nooby question but not really sure whats causing this.= at the moment.

With a low Fov i have the camera far from the payer looking down, with the grass foliage depending on the height theres some weird circular effect where it looks like parts of the material get culled if they’re outside that range.

not sure if theres a material culling feature or whatever could be causing it
thank for any help!!