On Fri, 19 Sep 2008 16:27:19 -0500, Sarah Houston
wrote:
Rarely. It's usually just fired clay.

Anywhere that sells clay flower pots will also sell the bottom dish, I
think that will be perfect for your use and they are very
inexpensive... I use them to grow wheat grass for my cats... they can
be used and reused over and over.

Is there any lead in them, or anything that could be toxic to birds?