I don't know where your daughter lives, whether it's a city lot or a
country property, but I'll tell a little story about my next door
neighbor, a number of years back. We all lived in a suburb on large
cul-de-sac lots. The neighbor property had been rented out, and the
back yard which had a few little Boysenberry plants, got TOTALLY out of
control under the "care" of the tenants. The Boysenberries took over
the entire rear yard, and where at least 7 feet tall. They were so
thick you couldn't get into them to do anything, other than perhaps
begin hacking with a machete.
The owner found the ultimate solution. . .They borrowed a couple of
little goats, and put them in the backyard. Within a week to 10 days,
the Boysenberries were nowhere to be seen. . .just bare ground! The
cute little goats had done their job.
The neighbor took the fat and full goats back to their owner, who was
glad to have not had to feed them for those days. When little berry
sprigs began to spring up once again from the old root stock, the
neighbor used Roundup on them. . .End of problem. The cost of Roundup
on those few sprigs/shoots, wasn't costly. If he had tried to spray
those bushes when they were 7' tall and thick as thieves, the cost of
enough Roundup to eradicate would have been prohibitive.