Answer: In general, if you did not plant it then it is better not to cultivate it. There are several different wild growing brambles that could have been introduced into the planting (by birds for example) as volunteers. Here are some good descriptions and illustrations of types commonly seen in New York and New Jersey you might find interesting.
The wild types can harbor pests and diseases (due to reduced resistance) that you would not want to introduce in your cultivated planting.
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