more than one can shake a stick at
A large quantity, more than one can count, as in Our town has more banks than you can shake a stick at. This idiom presumably refers to brandishing a stick as a weapon, but the precise allusion is unclear. [Colloquial; c. 1800]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.