Q: Can you tell me what makes a rose sprout shoots like this? It’s an old rose, maybe 15 yrs. old.
A: The thorniness reminds me of rose rosette virus.
but the balls of tiny leaves remind me of glyphosate damage.
I don’t see any red foliage that would confirm rose rosette.
This is a situation where only time will tell.
Let me know next summer how to rose looks.