Yesterday, I was forced to buy a bundle of new tree stakes, and I thought I'd make note of the reason why here, as it may prove instructive. The cider varieties we planted are all on the semi-dwarfing rootstock M26, which owing to it's lack of vigour requires that the trees are staked and tied for at least the first few years of their life. This prevents the tree from rocking in the wind and damaging the root ball, and failure to do this would almost certainly have resulted in our precious trees being uprooted in the strong gales we have experienced recently.
The stakes we used initially were a square section of tannalised softwood (see left-hand pic) bought from a large DIY store. They seemed to be just the job when we bought them, but proved slightly less so when we tried to drive them into the ground. The square section is not the strongest of profiles for this kind of work, and some broke at weak points whilst we tried to lump-hammer them in. Over the last couple of years I've regularly bumped into some of the posts with the mower, and in one case it snapped at the base as a result. All in all, not very impressive and it was time to replace these lightweight pretenders with the real thing. The stakes we went for are Gardman Tree Stakes (1.2m x 35mm, pressure treated, FSC softwood), a round profile stake, as shown in the right-hand pic. These have gone in much better, and are much sturdier in the ground than the previous stakes, and should hold our trees firmly enough until the day they can stand on their own strong roots.