alpha - I'd love to know where the helicopter is, I have never heard of it before.
You do need to mix other stuff with grass cuttings (especially with the volume you have), but in reality if you have an acre you presumably have *some* other vegetation there which you can use to mix.
Just establish a compost heap (loads of places on the web showing how to construct one, but in reality you can get away with just making a big heap) somewhere in your garden. Actually it might be worth establishing a few and spreading the load (of grass) across them. Add in kitchen waste (peelings, raw fruit remains, kitchen paper, etc . . . but not cooked food or raw meat) and let nature take its course.
You could also consider getting a wormery, perhaps in addition to the compost heap. While the compost heap relies on a somewhat passive process (heat building up helping to accelerate breakdown) the wormery relies on the active process of the worms eating and digesting the grass so this *may* help with the volume issue. Remember of course that the wormery would also require a mix of content as the worms wouldn't thrive on grass alone.
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