Hi Beth,
Yep, boysenberries can be aggressive! It's hard to see how much space there is between the trellis and the path. Are you sure you gave your boysenberries enough room? That's what I would start researching, if the boysenberries don't have the recommended space, you may need to move either the path or the boysenberries if you ever want complete peace of mind.
Some folks say it's
OK to trim them back during the summer and some say
you should never do it. Be that as it may, I think most would agree that letting them trail along the ground is going to cause pest and disease problems. Can you tie them up to get them out of your way and keep the plants healthy? You're dealing with an aggressive plant here. If you've been fertilizing, maybe pull back on the nutrient next summer and see how that affects yield? That's where I would start. In the end, it probably comes down to your priorities and what you can put up with. :)
Good luck with this!
Karl
Instagram:
@foodforestcardgame
Website:
FoodForestCardGame.com