The expenses relating to your CRP income are reported as Conservation expenses under the Farm Expenses section. Note that if your conservation expenses exceed 25% of the gross income of the farm, the deduction is limited to 25%, and any excess can be carried forward. Be sure you've calculated your conservation expense deduction correctly and that your expenses are covered by an approved conservation plan.
If your CRP expenses are not covered by an approved plan, report them under whatever farm expense category seems appropriate.