Reduce vegetation damage by drought
In urban areas, increasing drought damages vegetation. Most species of grass are not able to stand prolonged periods of drought. Trees and bushes can become seriously or irreparably damaged by prolonged periods of drought. In order to limit these effects on urban green, irrigation is required. This comes at the expense of the already scarce fresh water supply in times of drought.
The interspersed planting of trees in public green areas provides shade for the lower plants preventing excessive evaporation and cooler spots for city dwellers to sit. The trees themselves have deeper roots and are able to provide for their own water supply. Certain tree species are able to stand drought better than others.