stoopid answer time ... many rose thorns have an oval base so the thorn looks like it is 'floating' on the stem and will break away easily. Bramble thorns are more integrated into the stem. Rose stems are round mostly, some bramble stems are squarish with flat or even concave sides.
Brambles and roses have different growth habits and patterns, but I would imagine that won't help you at the moment.
Then there are the leaves, which are utterly different. The ol' net has some pictures no doubt
Thanks for the info re stems and thorns. Re leaves looking utterly different, you mean like this?
Not that different really? (not surprising seeing as they're part of the same family...)
Just worried about throwing the baby out with the bathwater when clearing thorny areas.
Also found this on a website : Bramble can also be confused with rose (Rosa spp.), which like bramble has five petals, compound leaves, and thorns, but bramble lacks the distinctive stipules at the base of the rose leaf. " so am now on the lookout for stipules
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