Everything GardeningRotoplast & Self Watering Planter Systems

We discovered a deep hole under a garden shrub. Yellow Jacket nest debris (cellular) was scattered in vicinity. Yellow Jackets were crawling in the hole. We have a considerable wildlife population on and around our 2 quiet acres. What would this digging animal be seeking?

I can only plant my vegetable garden near a black walnut tree. Something in the tree make-up prevents certain plants from growing. Which ones do better than others. Thank you