It's a bale Jim, but not we we know it

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Now that we've got our shiny new silage pit roof, and the latest state of the art covering on the grass, we don't need the hundreds of tyres that we used to use to weigh down the plastic sheet. Putting them on took all day and was a wet and dirty thankless job. But it's not so easy to get rid of the heap of old tyres. Today part of the solution arrived - a baler to compress them down to a neat solid shape (that apparently we will find a use for). James moved the tyres from our heap (with the Manitou) to another heap nearer the baler. One operator stacked them, and another loaded the machine, periodically pulling a lever to squash them down. Eventually the bale was wired together and moved away by James.

It must be something new round here, as we even had spectators - here's Jim wondering how many tyres in the bale.

How many do you think? First right answer wins a (virtual) prize.