This section is from the book "Commercial Gardening Vol3", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
This small weevil, which is only 1/6 in. long, is the cause of very serious loss to Apple growers. It occurs in Kent, Surrey, Cambridgeshire, Worcestershire, Herefordshire, etc. It is the cause of so-called "capped blossoms " (fig. 344).
The beetle is ashy grey, with a pale V-shaped area on the wing cases. It can fly, but is not very active on the wing. The female bores a hole by means of her long proboscis in the small blossom buds, and in each deposits a single egg. This changes into a creamy-coloured footless larva, which feeds on the inside of the blossom, which does not open, but which later turns brown and dies. Still in the blossom the maggot changes to a pallid pupa with dark eyes, and then the beetle hatches out, and escapes from the capped blossom by eating out a round hole in the side. The beetles live right through the summer on the trees, and in winter they hibernate under rough bark, moss, lichen, etc, on trees in and around the plantations. It sometimes attacks the Pear.
Old trees should be cleansed in winter by spraying with either caustic soda wash or lime-and-salt wash, so as to destroy their winter quarters. The beetles may also be jarred off on to sheets or boards covered with tar when they are seen to have started to lay their eggs.