[Avodah] Interesting Aspects of Tu B'Shvat

[Rich Wolberg]

What I find interesting about Tu B'Shvat is that though it is called the New Year for Trees, it is curious that the first of Tishrei is the new year for the PLANTING of trees and herbs. Tu B'Shvat is the new year for maaser of trees.  Also, I never understood why Shammai said the date is the first of Shevat but we follow Hillel who says it is on the fifteenth. All of the other three New Years are on the first of the month, so perhaps that is the reason Shammai said it should be the first of Shevat.
Does anyone have the answer?