I live in Mid Michigan and have planted seedlings every spring since 2000. I have been planting Red Oak, White Oak, Black Cherry, and Black Walnut. I plant 25% red oak, 25% white oak, 25% black cherry, and 25% black walnut they all grow well here. Should I change my % or add another species of tree. My plan is for someone (My kids) to harvest the trees in the next 30 plus years. Any ideas Thanks.