Actually there is a 4797 enterable entry form just for purposes like this.  If you enter correctly it will flow to Sch D.  But taxman's method would also work.  Schedule T is used if you established a standing board foot value when you bought land so you can take off cost against this sale.  Since this a small sale I personally would not look into that, but remember next time a client buys farm ground with timber to get a value of standing timber at that time.