A recently installed high-pressure sprinkler irrigation system watering turfgrass planted alongside a row of mature cork oak trees, with water ponding around trunks and the tree root zone.

Oaks planted next to irrigated lawns are subject to aeration deficit injury as well as infection by Phytophthora and other root pathogens. Credit: Laurence R. Costello, UCCE San Francisco-San Mateo
Credit: Laurence R. Costello, UCCE San Francisco-San Mateo