Yes, that is correct.... not all basswood is created equal. Do some googleing, and you'll find basswood grows in most every state from the middle of the US to the East coast, with Wisconsin having the largest number of trees on forest land. (see map)
I carve some local (Missouri/Arkansas) basswood but typically depends on the wood. It's been my experience that basswood can/will harden with age. I won't waste my time hand carving it if it's too hard. Some of the local stuff has streaks in the wood, which doesn't bother me if I'm going to paint it. If the streaks are extra dark and/or near rot, I often carve whimsical items, like old shoes. These actually add character to the piece and let these show through the finish (shoe polish, of course). Again, wood can not be too hard. This wood is typically light tan to darker tan to near brown (in spots or streaks) in color.
When I carve pieces where I don't want any streaks or blemishes, I use the "good stuff". This typically comes from the North... Wisconsin, Minnesota, Canada, etc. The farther North it grows, the shorter/slower the growing season. This results in a tighter grain, and a near white (egg shell ?) color. Northern basswood is easier to carve (not as hard as Southern basswood) and the go-to wood for a lot of carvers. As mentioned in many threads on SMC, Heinecke Wood Products is a very good source and the only supplier I personally would order online from.
http://www.heineckewood.com/
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