Before my wife and I moved to Colorado I used to say we had a ton of "stuff" - our belongings. I was wrong. When the movers weighed everything, I discovered we had three tons of stuff. One ton - 2,000 pounds - was just books.

These days I try not to buy so many. If I want to read something, I get it from the library. Otherwise, I know that sooner or later I will once again have to whittle down my possessions to fit the available space. I hate that. I get enough of it at work.

Deciding which books not to keep is the most painful task a librarian faces. You don't get into this business unless you love books. And like everyone else, we have the unconscious presumption that a once a book makes it to library shelves, it will be there forever. The Happy Hunting Ground of the Printed Word.

But libraries not only collect books. They have to get rid of them too.

We call this process "weeding," and we do it for the same reason a gardener weeds. We need to make room for fresh, healthy growth. Just because a book makes it to the library shelves, doesn't mean it stops getting old. Over time, and despite our best efforts, the paper yellows and turns brittle. The binding begins to deteriorate. Dust collects. The lettering on the spine starts to fade. Old books eat up shelf space. After a while, they actually scare people away from the new books.

Particularly in the non-fiction areas, we can't afford to keep books more than 5-8years. In some areas, even five years is pushing it. Old books, particularly technical books, have bad information in them.

How do we decide what goes? In general, the people decide. Every time someone checks out a book, it counts as one vote. Popular books get a lot of votes. So whenever we weed, we re-elect them to our shelves.

But sometimes we find that a book hasn't been checked out in a long time. And in the public library, a book that hasn't gotten a single vote in awhile gets kicked out of office. It's democracy in action.

Even when the People Have Spoken, that doesn't make it any easier on librarians. Some books - classics, for instance - we may choose to replace with newer copies. In our innermost hearts, we still believe that every book has its reader, and every reader his or her book. It's sad when one of our books goes unloved.

But here's the other thing, verified by countless libraries around the world. When we get rid of the older growth, the use of the newer material takes a big jump. Now patrons can find what they're looking for.

So where do new books go when they've been weeded? Often, they wind up in library book sales. From there they pass to precisely the places that please us most. They find good homes, with people who will love them.

Right now, we're doing something new: we have a contract with a company that takes everything we don't hold back for sales, and sells it for us on Amazon.com. We then get a share of the proceeds.

We went to this approach recently because of our push for RFID tags -- a technology that will allow our people to move materials much more quickly. Before we put the new tags on our items, we wanted to make sure these are items that our public actually wants and uses. So we're weeding in earnest.

Incidentally, we'll be looking for volunteers to help us with the tagging process. If you'd like to be a part of the conversion to tomorrow's library, talk to someone at your local branch.

I can guarantee that it's way more fun than moving.