Are blackberry vines toxic to dogs?

The blackberries themselves are not toxic to dogs, but the stems and leaves can be. The stems and leaves of blackberry vines contain small, sharp thorns that can cause cuts and abrasions on your dog's skin. In some cases, these thorns can also become embedded in your dog's skin, which can be very painful. If your dog ingests any of the stems or leaves, they can also cause gastrointestinal problems such as vomiting and diarrhea. In severe cases, blackberry vines can even cause kidney damage.