Abstract: An irrigation system for trees, vegetables, fodder plants and the like having a feeding network including main and secondary liquid distribution pipes, vertical pipes branched off the distribution pipes and conneted to substantially horizontal distribution tubes located above ground. Each such tube extends along a row of trees, or, in absence of trees, at predetermined mutual equal distances from other tubes. Each horizontal tube mounts liquid distribution cases, each positioned near a tree or, in absence of trees, at predetermined mutual distances. Each distribution case is provided with a plurality of peripheral radial slots through which pass a variable number of small slightly flexible, downwardly depending tubes made of dark plastic. At least some of the small tubes have their outlet orifices placed at a predetermined distance above the ground.