In terms of how you can find out if the wood is poplar or cherry -- I would start with reviewing any and all documentation you have that says it was cherry (be sure it didn't say cherry stain). Without documentation evidencing that you were promised and you paid for (solid) cherry, you will have a difficult time with moving this forward. Beyond the documentation, you obviously need to locate someone who can evaluate/identify wood, preferably someone who is qualified and who is willing to put their evaluation in writing. Once you have that writing, put your complaint in writing to the builder and include a copy of the assessment and of your original contract evidencing what you paid for -- cherry wood. Make a demand that the cabinets be replaced and provide a deadline. Whether you need or want to get an attorney involved is your call -- without knowing the costs difference, it is hard to say. Good luck.
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