A group of scientist from Chicago and Toronto conducted a study on the effect trees have in a community. The results of their study were quite substantial. Once the results were quantified, it was found that if ten trees were planted on one city block, each person received health benefits that equate to $10,000; that’s ten grand for each person! For info on the article can be found here.
The City of Los Angeles offers its citizens free trees for their communities through the City Plants Program. To sign up for City Plants, visit http://www.cityplants.org/. Several other cities offer free tree programs. A quick search can provide answers on how you can obtain a tree for your place of dwelling.
Don’t forget, many California trees are drought tolerant!