In order to avoid any slowdown or stop of the growth trend in the period of stronger vegetative activity, it is very important to ensure adequate water supply to trees, especially in summer. Some parts of the roots cannot reach the aquifers, therefore, in case of prolonged drought, emergency irrigation is necessary.
The irrigation system consists of sprinklers, but, year after year, modern sub-irrigation systems are increasingly used in the new plantations, since they ensure considerable water savings (evaporation is avoided) and reduce fertilization, because they are oriented towards the roots. The water requirement of an average poplar is 100 mm/month in spring and summer, emergency irrigation is carried out only if this amount of water is not reached.