The aim of this study is to examine the effects of semi-circular water harvesting techniques and some applications that improve soil water holding capacity to growing of olive trees. Experiment has been established in randomized block design, and micro catchment water harvesting bunds which are semicircular type were constructed in May 2015. Experiment subjects; A: the control subjects, local planting, B: planting in soil cleared it of stones (in 1x1x1 m sapling pit), C: adding 50 kg of soil organic material (OM) to soil cleared it of stones, D: adding 250 g polymer (water retainer) to soil containing 50 kg soil organic material and cleared it of stones, E: adding 500 g polymer to soil containing 50 kg soil organic material and cleared it of stones. The moisture content of experimental soils has been measured on an hourly basis with moisture sensors placed 25 cm and 75 cm in depth, as well as precipitation, air temperature, relative humidity and wind speed has been recorded by meteorological station and monitored by an internet application. Trunk diameter of sapling was measured in October 2015 is that at the end of first year of the experiment, and according to experimental subjects, annual differences in sapling trunk diameter cross sectional area was subjected to statistical analysis. The differences between saplings was a 95% probability. Accordingly, the most increase was in D subject with 133.09 mm2, it was followed by E: 105.48mm2; C: 98.98mm2; B: 94.27 mm2 and A: 77.95 mm2 respectively. While the change in saplings trunk cross-sectional area at the end of second year of the experiment was statistically reliable at 95% probability, D subject was ranked at first group with 459.98 mm2. It was followed by B subject with 445.14.mm2, E: 432.94 mm2, C: 404.35 mm2 and A subject with 206.67 mm2 respectively.
