I gather fall leaves for use in my deep litter in the run year round, as as compost for the garden. I save paper feed bags use them to store bags of loosely packed, dried leaves in an unused greenhouse.
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(not many bags left when fall rolls back around)
My birds love piles of dried leaves, and I dump a bag or two when there's not much else for them to mess with (i.e. in summer they tend to get grass clippings instead of leaves) and let them flatten the piles and distribute the leaves around, until they break down over the course of weeks.
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(couldn't find any good pics with fresh piles, but obviously these were recently added - chicks and adults approve!)
As I have a willow tree overhanging my run I do get a lot of branches and leaves dropping around it. I leaf blower the leaves into the run itself, and smaller branches can go in as well.