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.
Practically everyone concerned in the cultivation of plants has grasped the fact that fungi can cause diseases. This mostly accounts for the statement repeatedly made, that diseases are much more prevalent now than in times past. There is no evidence to show that such statements are correct. They certainly prove that more attention is being paid to the subject than heretofore.
WIRE TRELLIS IN A PEACH HOUSE AT THE HENDRE, MONMOUTH.
Showing crop of fruit and how the shoots are tied to the wires.
A peculiar disease of Peach trees has been recorded from many localities of late. In the spring the leaf buds on the terminal two-year-old shoots expand quite normally, without the slightest suggestion of disease, but just about the time when the blossom is fully expanded, the young leaves suddenly wilt, turn brown, and die within a few days. This is followed by the browning of the petals and the drooping of the flowers, which soon die, but remain hanging for some time, as also do the leaves. The general appearance of such shoots suggests frost, and most probably their death is frequently attributed to this cause, which is, however, not correct, the death of the shoot being caused by a parasitic fungus. During the summer the shoot changes to a deep claret or brown colour, shrivels, and dies. About midsummer, when the dead leaves and flowers have been removed by wind and rain, the dead shoots are very conspicuous, projecting as spikes beyond the living portion of the tree on every side. If such dead shoots are examined the following spring, they will be found to be more or less thickly studded with minute, dull, orange-coloured hair-like bodies. These are the spores of the fungus that ooze out in gelatinous masses, which adhere to the feet of birds or insects, or are washed by rain on to the young shoots of the season, which become infected and perish in turn. From the above account it will be seen that no new wood can be produced when the disease has once gained a foothold, as the young shoots are infected as soon as they appear.
The obvious remedy is to remove all dead shoots during the winter. When a tree has been infected, it would be wise, in addition to removing all dead shoots, to spray in the spring, when the shoots are about 1 in. long, with self-boiled lime-sulphur mixture (see p. 50). [g. m.]