I wonder if the snow loves the trees and fields, that it kisses them so gently? And then it covers them up snug, you know, with a white quilt; and perhaps it says "Go to sleep, darlings, till the summer comes again.

This quote is describing how gentle and kind snow can seem. It’s saying that it seems like the snow loves trees and fields, and kisses them with a gentle touch. The snow covers them in a white blanket, like gently tucking them in, and tells them to sleep until summer comes again. This is suggesting how comforting and protective the snow is for the trees and fields, like it is taking care of them until summer returns.