anyone know where I can learn more about when a lake would qualify to start harvesting the 14 inch class of bass?

The lake I am curious about is 224 acres and loaded with 2 types of bluegill up to about 6-7 inches. A  8 yrs ago the lake (reservoir w/landowner acess only) was lowered about 10 ft to replenish water supply.   We used to catch some 6's back in the day. Some large fish where taken while it was lowered by people sneaking in and a few guests,etc.. The water is gin clear and now that the lake has fully recovered, we catch consistent 4-5 pounders but nothing larger. Wondering if we should start pulling certain size bass out of there. also, no minnow based forage that we can tell of and if there are minnows in there, they certainly aren't prominent.  It's also loaded with crays.

Add shad. You can weed out some of the smaller fish which is good and healthy for the population. What I would is figure out what is the average size of the mid sized fish. If you have a high population of 14" bass and the bigger fish are few then set it at 14" limit. If you have a high population of 12" fish and 14" fish are few set it at 12" limit. But I would set a slot limit. This would protect the larger fish from being fished out.