The method of calender jujube

Calender jujube tree left hand, right hand axe, counterclockwise, from the trunk longitude of 30 meters, from bottom to top, axe vertical trunk calender injury, the depth to reach the tough skin without damaging xylem is appropriate. Axe mouth row to the general horizontal distance of 2 cm, line spacing of 2.5 cm, each time 3 lines, so that they crisscross each other, the opposite mouth is easy to cause holes, the wound is not easy to heal.