I have a grunt call that has several different tones:
1- Fawn Bleat
2- Doe
3- Young Buck
4- Mature Buck
I am hunting between Oct. 1 until Oct. 18, in Northern Michigan, before the rut. Which call should be most effective and why?

It depends on what you mean by " most effective" . The doe bleat will bring in more deer, but the buck call will bring in a buck or two. the mature buck grunt might chase away anything but only the biggest buck, which might not be in hearing distance.

I wouldn' t go too aggressive that early, I personally through 20 years of calling whitetails would vary between 3 and 2 assuming your looking to call in bucks...but I rarely blind call....blind call is calling when no deer are present visually. Once I spot a buck, I give him soft grunts to get his attention and call him in. On most occassions, 2 grunts is all it takes, one to stop him or get his attention, the second to reel him in...now notice I said most occassions...there are times, they will hear you but have no interest. I rarely get aggressive at that point, they usually will walk away...I' ll give a couple more soft ones cause I know they hear me and do not want to come...I may also softly tickle anters together and through in an occassional doe contact call. If they are interested, they will come, if they are not....you will only spook them if you try too hard. Let them go...they know they heard that deer and may come back moments later but getting too aggressive or trying too hard might push them off for good.