A. To guide the appropriate use and development of land in a manner which will promote the public health, safety, morals and general welfare. Generally, you may deduct up to 50 percent of your adjusted gross income, but 20 percent and 30 percent limitations apply in some cases.Add the Act of donations for land for editing. Call 1-800-729-SAVE or fill out our contact form. Purchasers that failed to complete their payments within three months after due date of the last installment forfeited the property.