The Undervalued trees of L.A. from LA Times Editorial p.9, January 2, 2019

Paragraph 7 and 8 Quotes 
"A mature urban forest and dense canopy can provide relief on the hottest days -- shaded surfaces can be 20 to 45 degrees cooler than those in direct sun -- and reduce air conditioning demand, which helps ease the strain on the city's electrical grid."
"The roots also capture and store rainwater, which helps the city make better use of its water supply at a time of more extreme weather conditions and wider swings between periods of drought and flooding."