Only cash contributions (e.g., checks, credit card charges) are acceptable in 529 plans. You’ll have to sell the stock and donate the proceeds. If the stock has appreciated, you’ll owe capital gains tax on your profits; if the value has declined, you’ll be able to take a tax loss.
A statutory method of depreciation allowing accelerated rates for most types of property used in business and income-producing activities during the years 1981 through 1986. It has been superseded by the modified accelerated cost recovery system (MACRS) for assets placed in service after 1986.