Community composting groups can get really hung up on their shredder. It can become the main focus for their activity. Don't forget that composting is the most important thing to do.
If you have plenty of space you can do several things. Long term heaps composed mainly of woody materials will eventually rot and in the meantime become wild life refuges. If you can make a heap carefully and finish off with a layer of soil or compost on top you could even grow plants on it. However if you are contemplating this it's probably more sensible to do it properly and build a "German mound garden".
To do this first mark out a piece of ground about 4 to 5 feet wide and as long as you like. Remove the top layer of soil, a spades depth (or spit). Put this earth alongside your marked out area, you will need it later. In the centre of this trench dig another spit this time only about 18 inches wide. Put this subsoil to one side within the main trench. Make a core in this deepest trench, of all the thickest woodiest materials and try and fill as much of the air spaces you can by backfilling with the subsoil. The mound garden is then built in a similar way to a conventional compost heap except that the layers become progressively 'softer' or more composted the higher it gets, finishing off with the spit of soil first excavated.
When it has been raked into a good shape, (the sides should not be too steep otherwise watering can be a problem as the sides tend to wash away), then it's ready to be sown with its first crops. Either choose shallow rooting crops because of the potential nitrogen robbery, or grow legumes, which provide their own nitrogen.
Don't forget that much woody material is very useful for gardeners. Save good poles and sticks for supporting plants, especially peas and beans. Hedges can be created and augmented using all manner of woody material. They shelter all kind of wildlife as well as creating excellent wind breaks to protect crops.
Finally wood is a fuel.
It's crazy to expend a lot of energy with a shredder reducing perfectly good firewood to wood chips if there is a local need for it, as fuel. Having said all that, shredders do have their uses. For one thing you may not have all that amount of space to devote to long term composting. A shredder quickly reduces the volume of your materials and makes them ready to include in your compost heap or mound garden. Or why not just use them straight away, as a mulch?
Don't get carried away with shredding, as it's easy to start putting all sorts of unsuitable
materials in. All you're going to do is make things difficult for yourselves. The machine will either clog up because the stuff's too wet, or you'll break a hammers, because the materials are too hard, thick, or stony. Have a long term heap for dodgy materials and go through it once a year or so, most of it will have turned into compost and the residue you can either sieve out or chuck back for another year. If you're using the shredder you can't be heard without shouting and its not what I call a pleasant community activity.
So be sensible with your shredding. Examine all the alternatives first. Try and make compost without a shredder. You might find you don't need it at all.
