 It's time to look for a tree, not a normal one, but a Christmas tree. Holiday season is upon us and Christmas trees are piled up waiting for a buyer. And what is it special about it? For starters, the smell. I think smells are very evocative, you know. They produce reminiscence quicker than sights or sounds, you know, because it goes straight to the hippocampus. Most of Christmas trees has been in the same Alston's parking lot for more than 40 years and his owner, Gris Gregory, has some loyal customers who have been here from the beginning. Great generations are coming right to the same spot with the same guys who have been running this place. When you come to buy a Christmas tree, you have to look for something in particular. But how can we decide which one to buy? Well there's a process that you go by. First you pick up the tree, push it down on the ground as hard as you can. You watch the way in which the branches fall out. Then you look also to see whether or not any of the needles fall off. If the needles are falling off it's too dry, you don't want to take that one. If the branches don't fall out into a nice kind of full way, it's probably a little gangly and you may want a different kind of tree. So you want that fullness and you want the leaves to be really bound, the branches and the needles to be very bouncy. Prices go from $20 to $60 for trees like this one. And once you decide which one to bring home, you just have to, well, go back in time. So I think it brings people, it returns people to the roots of, you know, the first Christmas tree, etc. You know, it reminds them, triggers memories. After you buy your tree, and I guess it's not as fancy as this one, you can come here to Quincy Market and buy the necessary ornaments to try to replicate it. I'm Emilio Domenic for BU News Service.