What is this?
We are renters and our first summer here. I went to prep the yard for our NW rainy season and I uncovered this. Does the arborvitae have a disease? Could this have caused our pet illness since we’ve moved in? How do I fix this? Thank you for any answers
It looks fungal but it is hard to diagnose just from photos. I suggest that you scoop up a sample and take it into the Master Gardeners at the Yamhill County Extension Office. Their address is 2050 NE Lafayette Ave, McMinnville. Their hours are 9-4 Monday through Friday. They will be able to look at your sample closely to determine what it is and what you should do about it.
As to why your pet is sick, that would be a question for your veterinarian.