|what could I plant under and around oaks that does well on slopes and the deer won't eat?|
|Oaks are very particular about sharing their space with other plants. They generally do not like as much water as other plants need. With this in mind, the following plants will grow in part shade, with very little water and should make good companions to your oaks: Achillea (wooly yarrow), Duchesnea indica (Indian mock strawberry), Cotoneaster, Hardenbergia (lilac vine), Sollya heterophylla (Australian Bluebell Creeper), and Ribes viburnifolium (Catalina Perfume).
Dealing with deer is a whole new ballgame! Hungry deer will eat almost anything, especially if the population is large and food is scarce. They typically do not bother the above listed plants, but your mileage may vary.
Best wishes with your garden!