"Tu" (the Hebrew abbreviation of 15th) in the month of Shvat was set (Hillel's opinion generally overrules Shammai's) as the beginning of the tithable year for tree fruit: Calculating the tithe on fruit starts again for fruit that sets after that date.
My commute to work every morning is not typical. I drive through the Roaring Fork Valley with majestic, now snow-covered, mountains on my left and my right. The sky is often a clear, bright blue, and the sun glimmers off the powdery snow that shifts in the wind. I am the cantor at the Aspen Jewish Congregation, and I certainly feel blessed to live and work in such a beautiful place. This quote from Isaiah is particularly fitting for this part of the country, as the people here are very in touch with the nature around them - often finding their spiritual center while skiing a run or hiking in the hills.
Tu BiShvat, the birthday of the trees (or the new year of the trees) is a minor Jewish holiday.
Here is the quintessential Jewish question: How do we emulate God? We are told that we were created by God. We are told that we have a divine spark within us.