A remarkable feature of American Jewish life over the past 40 years has been the growth of Jewish environmentalism. From origins on the fringes of the community, dozens of organizations today enlist tens of thousands of Jews every year in a plethora of activities that include the “greening” of synagogue buildings, organic farming, and environmental lobbying under a Jewish umbrella. The Union for Reform Judaism devotes several pages of its website to a programmatic initiative aimed at “integrating Jewish values, learning, and actions that promote shmirat ha-adamah—protection and renewal of the world.” In the annual observance of Tu b’Shvat, once a footnote on the liturgical calendar, Jewish environmentalism has even created its own holiday.