For a land donation, you must have Form 8283 and appraisal, the IRS will not allow your deduction.

After you E-File your Tax Return, you will need to mail in Form 8453 with your Form 8283 and related documentation, including your appraisal and deed.  TurboTax will include this in your E-file instructions. 

Here's where to enter the donation:

Manually enter your charitable donations directly into TurboTax:

1. Open (continue) your return in TurboTax.
2. In the search box, search for donations and then select the "Jump to" link in the search results.
3. Answer Yes to Did you make any donations to charity?
4. Answer No to Do you have an account with ItsDeductible Online?
5. On the next screen, answer Yes to enter your donations for 2018.
   
6. Continue with the onscreen instructions.