This year's leaves in front - last year's (back right) - and the previous year's (back left)

We all know that piles of stuff gets smaller as it decays, but don’t usually get to see the difference. I have a graphic example every fall, however, in my leaf pile.

We have long maintained a compost pile for leaves, at one end of our old chicken house. It’s a three-pile system; each fall I rake the leaves into a big pile (the kids are gone to college, so nobody plays in it, alas) - call that location A. The next fall I move that semi-composted pile over into location B and pile that year’s leaves into location A. The next fall I move the two-year-old pile from location B to location C, move the year-old leaves from A to B, and put the new leaves in A. By the following spring, the stuff in C (now 2 1/2 year removed from trees) is composted enough to be distributed in flower beds and the like.

As a result, every fall I have a pile of fresh leaves, one-year-old leaves and two-year old leaves, side by side. You can see a picture of it above (a crummy picture, I’m afraid - I’m no photographer and my point-and-shoot is old). It doesn’t show all of this year’s leaves, but it gives a sense of how much they shrink in volume in the first year. I’ve estimated that over the course of one year the leaf pile reduces in volume by 90%-95%, and over the following year, they reduce in volume by another 50%.

In case you’re wondering, that yellow board behind the old compost is a hollow-core sliding door that was on some closets when we moved here. On the far side of it, not visible in the picture, is the kitchen compost. I keep it separate so that if anybody wants to play in the leaves, they won’t encounter old coffee grounds and eggshells.

Tags: compost; mulch