I planted a cherry tree last year which produced a lot of leaves and only one cherry but it was a very good cherry!  Suddenly the tree died.  Before that I noticed that something had been burrowing into the ground near the tree but never found out what it was.  Today I dug up the tree to plant another and found lots of very fat grubs among the roots, any ideas what they might be? I have attached a photo...

I think they grow up to be very big beetles.It appears the adults lay their eggs in animal manure or rich compost and the resulting offspring munch merrily away,unseen on the plants roots.Worth repotting plants if they are looking a bit tired just to check.

Many thanks for the replies.  I'll see what I can find to get rid of the B's.

I thought they were stag beetle larvae anyway we lost a cherry tree to them this year

They may well have been stags Hazlenut.  I think (but don't quote me) that all beetles have a grub larval stage that will attack roots.  The reason I plumped for chafers was that I sent a link to susanita's post (with piccy) to a mate of mine who's a pro horticulturist and he said "deffo chafers".  Don't think it matters as the same remedies should work on all types.  Regarding horticultural supplies, I've found most of the local "Jardinieres" much less comprehensive in what they stock compared to UK.  I haven't even managed to get hold of standard seed trays.  However, I find the co-operatives usually carry most remedies and feeds etc. and the lads know a thing or two.