Intro: Growing Cupressus arizonica with drip system of irrigation. To find out whether drip system of irrigation could be usefully employed to raise trees at Ziarat (2440 m A.S.L.), av. ann. rainfall 380 mm, average maximum and minimum temperatures 18.3°C and 4.1°C respectively, a study was started in May, 1976 using Cupressus arizonica as the test species. The method involves supply of water direct to the plant roots through sub-surface irrigation. Since there would be no loss of water due to evaporation or seepage, the plants are supplied with a quantity just sufficient for their survival and growth.