An adjustable spring grizzly bar material separator provided and includes a plurality of flexible tines, a cassette, wherein the plurality of flexible tines are each coupled on an end to the cassette, and a first set of spacers removably coupled within the cassette between the plurality of tines, wherein the first set of spacers separate the plurality of flexible tines a first predetermined distance to set the size of material that is to be separated from an amount of aggregate flowing over the tines. The material separator may also include a second set of spacers; the first set of spacers is replaceable with the second set of spacers, wherein the second set of spacers separates the plurality of flexible tines a second predetermined distance, the second predetermined distance being different from the first predetermined distance.