Hi Dianne70,
Based on each state's income tax filing requirements, if you sold a land investment for more than its historical cost, you could be subject to state income tax in that state, if there is a state income tax and then additionally subject to state income tax in your resident state, if there is a state income tax, but then benefit from a Credit for Tax Paid to Another State on your resident state tax return. While this could or may avoid double taxation, you could be subject to different tax rates in both states or no state income on either or one or the other.