[Shuichi is also not sure what it means, and he's the one who planted the thing. All he knows is that it was apparently Very Important to replace it. And since nothing seems to have gone horribly wrong as a result...they're probably fine.]

Right over there, actually. [He points towards a small well a little ways away.] I found a leaf from the original Tree of Life on the ground over there, a few days after we got here.