Codling Moth In the old country, in the other century, they used to daub apple and pear tree trunks with treated tar distilled into oil, their bases wrapped in hessian on which the gunk treacled down in a slick, a gloop of gold-brown syrup on black web and bark—to no avail. Once in the tree it would never be gone: eggs hatched on leaves, caterpillars tunnelled the fruit; half the delicious were golden, the others dun. Here and now, above the possums’ scratches and scats, Carbaryl’s getting the worm in its guts but when you spray it’s either too soon…