Trees do a lot more than provide shade and look pretty. For example, according to the National Tree Benefit Calculator, the 31" diameter Little Leaf Linden (Tilia cordata) outside our office provides $108 in benefits per year divided among stormwater filtration, energy production, improving air quality, and atmospheric CO2 reduction. If you're interested in how much a particular tree is worth, find out its species and trunk diameter and visit: http://www.treebenefits.com/calculator/
Little Leaf Linden (Tilia cordata)