The Annual Fall Leaf pick-up for City residents is scheduled for September 24 - November 20. Only leaves will be picked up.
If branches or other debris are in your leaf piles, your pile will not be picked up. Leaf piles left in yard areas cannot be picked up due to the potential damage to yards, sprinklers systems, or landscaping by the trucks and equipment used in the program. The Streets Division asks that leaf piles not be placed near utility poles, guy wires, fire hydrants, mailboxes, or other obstructions that would prevent their equipment from accessing your leaf pile.
Original source can be found here.