This section is from the book "The Balance Of Nature And Modern Conditions Of Cultivation", by George Abbey. Also available from Amazon: The Balance Of Nature And Modern Conditions Of Cultivation.
"A family of blackcaps in a cherry orchard commit great havoc," says Mr. F. Smith. "They do not eat a quarter of the fruit they pick: they are also very fond of raspberries and figs." In the garden the blackcaps take a heavy toll of late sweet cherries, raspberries and currants for services rendered in consuming aphides and small caterpillars, and are difficult to exclude by netting. This, to be effective, must not be larger in mesh than that known as pilchard, and there must not be any holes in it or apertures by which the birds can gain access to the fruit, for the blackcaps are very prying, and the worst pilferers of fruit of our summer visitors.
For great service in respect of destroying small leaf-rolling caterpillars on fruit bushes or trees and ligneous plants generally, also for eating caterpillars of the white cabbage butterfly, this bird takes a little ripe fruit, such as late cherries, currants and raspberries. Its attacks, never very pronounced, may be warded off by small mesh netting.