If you cleared land to facilitate installing a fence...the expense for the clearing of brush/trees can be added to the capital investment of the fence and depreciated on form 4562. Dozer expense, fence cost, fence labor cost should all be added together and depreciated.

If the expenses are not related to soil and water conservation, but the periodic and necessary clearing of brush or removal of sediment from a drainage ditch to facilitate the planting of a crop (grazing grass) you could elect startup expenses and amortize on form 4562 Depreciation & Amortization. You may elect to take the max $5000.00 the first year and amortize anything above the first year max election of  $5000.00 over the next 180 months on Form 4562.

Any major dozer work to fill ditches, reroute water, clear timber is considered land improvement, not periodic maintenance, and cannot be deducted as an expense, but is rather an addition to the basis (purchase price) of your real estate. Keep records of improvements...when you sell your land the value of improvements added to the original purchase price will lower your capital gain.

The IRS rules for farm land improvements are often vague and confusing. I have used these rules for years and never had a problem.

Best of luck with your new business!