Stone Fruits: Peaches and Nectarines 141 



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 in- 

 fected 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.] 



4. INSECT PESTS 



The Peach Scale (Lecanium persicce). This is usually found on 

 peaches under glass, but now and then occurs out-of-doors. It also occurs 

 on Apricot, Nectarine, and Vine, rarely on Plum. 



The adult female insect is dusky yellow at one time, then becomes dark 

 brown, pale in the middle with dark transverse bands, oval and hemi- 

 spherical in form; later, she becomes reddish brown. Eggs are laid about 

 the middle of May, and the larvae hatch under glass in mid-June. One 

 female lays as many as 2000 eggs. No male is known in this country. 

 The ova produce yellow to pale-red larvae which may become later greenish 

 or pale red, and which emit very long tine glass-like filaments from both 

 ends. These wander about and at last fix upon a definite abode and grow 

 into the adult female scale insects. They mainly occur on young wood, 

 and there they produce discoloration and the shoots may die away. 



TREATMENT consists of winter spraying with caustic alkali wash and 

 spring treatment with paraffin emulsion. 



Other Peach Pests. Winter Moth (Cheimatobia brumata), Peach 

 Blossom Moth (Thyatira batis), Cushion Scale (Pulvinaria vitis), Peach 



