Gerald has a robin. Or, to be precise about the hierarchy, a robin has Gerald. It turned up in autumn and simply took possession, the way robins do, and now it treats a nine-hundred-kilogram bull as its personal estate, its transport, and its dinner service. It rides on his back. It perches on a horn like a figurehead. It supervises the grazing from the gate with the stern air of a foreman. When Gerald moves to fresh grass, the robin moves with him, because Gerald is, frankly, the best thing that ever happened to it. There is an ancient bargain underneath it. Long before there were gardeners for robins to pester, there were great grazing beasts, wild cattle and boar and bison, turning the earth and flushing out insects wherever they went. That famous robin boldness, the way one sits a foot from your spade with an expectant eye, was never about you. It is about the enormous animal you are standing in for. For thousands of years, a robin's finest meal ticket was to shadow something huge, heavy, and permanently eating. Gerald is that something. Every hoof-fall in the wet grass turns up a beetle, a grub, a startled spider, and the robin is there to collect the rent. Gerald neither minds nor notices, which in his case comes to the same thing. So one of the oldest partnerships in the country plays out in a field near Hereford. The little red tyrant, convinced he owns the bull. The bull, serenely letting him believe it. Gerald grazes. The robin rides. Neither has read a word about the other, and between them they have it perfectly worked out, which is more than most of us can say.