Today, in Israel, cutting down a fig tree in Tzfat is not something you can get away with easily. Several years ago, I volunteered with the Israeli city’s municipality. One day, my fellow volunteers and I were tasked with helping remove an unlucky tree from the town center. The tree would have blocked the view at an upcoming civic event.
However, civilians interfered. Several passers-by stopped to tell us what they thought of us cutting down this innocent tree. This is not surprising, considering Tzfat’s history. Tzfat is widely known as the birthplace of Kabbalah, Jewish mysticism. Kabbalists in Tzfat invented the Tu B’Shevat seder in the 16th century and, consequently, the people of Tzfat take their trees seriously. Tu B’Shevat celebrates the “new year for the trees.” The holiday occurs each year on the 15th of Shevat. This year, Tu B’Shevat is Feb. 10. In the 21st century, Tu B’Shevat has become a day of Jewish environmental awareness.
The Torah explicitly prohibits cutting down fruit trees in Parshat Shoftim, Deuteronomy 20:19-20. When the Israelites go to war against a city, the besieging Israel army is forbidden to cut down fruit-bearing trees to build war machines. The rabbis extend the prohibition in the Talmud, reasoning that if cutting down the trees is prohibited during war, how much more so that it should be prohibited during times of peace. Eventually, this extension leads to the concept known as Bal Tashchit, essentially a prohibition against any waste.
There are two lines of reasoning for why trees should be protected: a moral argument and a utilitarian argument. The first comes from Rashi, a famous commentator on the Torah, who wrote that the reason for the prohibition is because a tree is not involved in the conflict, so it should not be harmed. Notably, Rashi’s argument would seem to include non-fruit bearing trees under the law’s protection. The commentator, Ibn Ezra, makes the utilitarian argument that the tree produces fruit, and cutting down the tree symbolizes the destruction of the food supply upon which humans depend. While non-fruit bearing trees appear to be left out of Ibn Ezra’s injunction, bringing modern environmental science into the discussion allows one to make a good case for protecting non-fruit bearing trees under rabbinical law as well.
Rabbinic discourse concerning Tu B’Shevat is (pardon the pun) rooted in scientific understanding. The legendary scholars, Hillel and Shamai, debated whether Tu B’Shevat should be on the first day of Shevat or the 15th. Their debate centered on which day the trees begin to make use of the next year’s water. The rabbis’ keen observations of the hydrologic cycle found that most of the year’s rain in Israel falls between Tishrei (October) and Shevat (February). These findings remain true until today. In recent years, Jerusalem’s average October through February rainfall was 70 percent of the city’s annual rainfall. Hillel’s argument won on the basis that Tu B’shevat is four months after Sukkot, when the next year’s rainfall is said to be decided. The four-month delay is because trees are dormant during the winter. Thus, they are not relying on the current year’s water.
Science tells us some pretty obvious things about trees. They are tall and wooden. They take water, carbon dioxide and sunshine as inputs and produce oxygen and more trees. Some of the less obvious scientific facts one can learn about trees include the idea that in some parts of the world, trees are responsible for a good deal of precipitation, as in the Amazonian rain forest, where trees evaporate massive amounts of water into the overlying air, catalyzing cloud formation resulting in almost daily rain. Trees can produce water, but (more obviously, perhaps) they can take it away. During the early 20th century, the Jewish National Fund planted thirsty eucalyptus trees in northern Israel to drain swampland, eliminating a malarial mosquito habitat. These fun-facts aside, trees are so intimately connected with their surrounding ecosystems that cutting them down in bulk would seem to fall under the prohibition of Bal Tashchit, even from Ibn Ezra’s utilitarian perspective.
Tu B’Shevat is a day to celebrate trees and their role in our lives. There is a quote from Rabbi Yochanan Ben Zakkai in Avot de Rabbi Natan 31(B) that sums up the importance of trees in Judaism: “If you have a sapling in your hand, and someone says to you that the Messiah has come, stay and complete the planting, and then go out to greet the Messiah.”