Conservation of water, soil and energy is of utmost importance, various approaches have been tested in a practical environment, and from our evidence, under sowing of crops might play an important role. There are two practical approaches that were once neglected, namely under sowing cultivation where various species are simultaneously grown with or between plantings of a main crop. These have been researched in multiyear field studies.  Under sowing is the practice of seeding one or more crops at the same time as the main crop, where only the main crop is harvested. Under sowing of crops might play an important role.  For example, under sowing of spring barley with alfalfa helps to: Fix nitrogen through the symbiotic rhizobium of legumes. Possibly a little nitrogen will be available for the main crop but more will be available for following crop; Increase ground cover and root penetration to combat soil erosion and increase traffic ability; Produce humus to enhance soil fertility and soil structure.  Our trials were carried out at the Institute for Plant Protection and Ecological Agriculture in 2008-2010 (Chisinau, Moldova) with focus on the research field. In addition to trials on small plots of land, there were also large-scale field trials on commercial farms. From the outset, importance was placed on practical implementation by introducing so-called “on-farm research” methods. Important results – statistics attest a guaranteed decrease of weeds and an increase in harvest in our trials by under sowing legumes into summer cereals. Yields were significantly higher with under sown crops.  Results from scientific trials were: Spring barley alone 1713 kg/ha (100%); Spring barley+ Alfalfa 2173 kg/ha (460 kg=+27%); Spring barley+ Alfalfa+ White clover 2174 kg/ha (+461 kg=+27%); Spring barley +White clover 2077 kg/ha (364=+21%). Spring barley grown with Alfalfa produced significantly higher yields than a pure crop. Alfalfa has a deep rooting crop which can sustain dry matter production at times of low rainfall. Under sowing significantly reduces the numbers of weeds. On average, weed dry matter is 34-49 % less in the under sown crop. This may be attributed to the drastic decrease in weed competition; the subsequent crop also profited from the nitrogen fixed by the legume. Number of weeds/weight (g). Spring barley alone 38.0/2.5 (100%); Spring barley+ Alfalfa 16.2/1.2 43%/48%); Spring barley +White clover 17.4/1.4 (46%/56%); Spring barley +Alfalfa+ White clover 12.8/1.6(34%/64%). White clover and Alfalfa have proven to be suitable for under sowing in our trials, where under sowing of these legumes significantly reduced weediness. Conclusions 1. Conserving farming systems are vital for the future, and practices such as good crop rotation, selection of resistant varieties and seed quality are indispensable.  2. The above results show that under sowing  crops can be valuable component of conservation farming.  3. Under sowing significantly reduces the numbers of weeds. On average, weed dry matter was at the 34-49 % less in the under sown crop.