The favourite dog medicine is couch grass. When the dogs cannot get it they will utilize other grasses. Their next choice seems to be wild oats.
Of the non-grassy plants, favourites are cleavers, dandelion, lemon grass, fumitory, wood-sage, fennel, mustard leaves and flowers, strawberry and borage. Also chosen are garlic leaves (especially the thin-leaved type), bramble leaves, mulberry leaves (in quantity), and fig leaves (in small amounts).
With all this herbal knowledge instinctive to the dog, it is sad that dogs often kept in enclosures in which all vegetation is soon spilt by trampling or by soiling with urine and faeces, cannot get their vital herbs fresh from the earth. Herbs can, however, be planted in pots and do well grown in that way.