lo Sept., 191 .2.] 



P) (,pagati())i of Fruit Trees 



l\acli Curl (K.xoascits df form tins. Fckl.). — This parasitic fungus disease 

 is confounded with the crimping and curling of the foliage and twisting 

 of the terminal ends of young shoots, caused by an attack from Peach Aphis 

 (black and green species). However, a very sligiit practical knowledge of 

 this fungus will serve to distinguish its workings trom that of Ajjhides 

 When the growing buds are attacked, the leaves, and very often the stems, 

 become swollen, fleshy, distorted, and curled, changing in colour from green 

 to a ruddv or dirty gifcy, whilst from aphis attack, the foliage and shoots 

 become crimped and curled only. If neglected and the weather and other 

 conditions are favorable, this fungus will spread rapidly, and do consider- 

 able damage to the growing peach and nectarine buds. Some varieties are 

 more susceptiljle to attack than others. If neglected the inroad of the 

 disease on the well-known variety of peach, Elberta, is so severe that the 

 growing buds either die out or become weakened 

 and useless as a .sound type for planting out. 



Treatment. — When selecting buds in the autumn 

 for propagation purposes, .secure them, if possible. 

 from trees that were free from attack, or trees 

 that were well sprayed in the spring, strictly 

 avoiding anv growths ha\ing a distorted or swollen 

 appearance. The buds should receive a spraying 

 with Bordeaux mixture or Lime-sulphur wash as 

 soon as they start to move in the spring. Place the 

 nozzle Oi the spray close to, and direct the wash 

 well into the buds, using high pressure. This is 

 an all -important factor when attacking this fungus 

 and. indeed, most other disease of a like nature. 



The buds should be closelv watched, and if 

 there is the slightest sign of attack a further spray- 

 ing should be given. This will be when the growth 

 of the buds, which is rapid, is from i inch to 

 6 inches in length. If no steps have been taken 

 to spray as a deterrent, and the buds are attacked, 

 all sw^ollen or distorted leaves should be cut away 

 and burnt, and spraying proceeded with at once to 

 prevent spreading. If the stem is attacked, reduce 

 the growth back into healthy wood and at a basal 

 bud. (See Fig. 73.) 



If the stem is attacked along its whole length, 

 the growing bud is ruined and worthless. Having 

 to cut away diseased leaves or reduce back the growth at all. like 

 I^ig- 73' i'^ a very poor secondary operation to fall back upon. 

 This check to the growing bud is generally so severe that at best only 

 a poor type of tree is produced. The di.sease is more prevalent in wet, 

 cold districts, and where trees are growing in wet, cold, and undrained 

 s?ils. Well-drained and aerated soil is an all-important factor in the propa- 

 gation and cultivation of the peach and nectarine. Yearling pruned trees 

 in the nursery row should be sprayed when the buds are bursting and again 

 when the leaves are developing. 



Prime Rust {Puccinia prinii. Pers.). — To the kinds of stone fruit trees 

 -subject to attack, this disea.se seldom causes serious harm in the nurserv 

 row. As a fact, the fungus usually appears after the trees have made 

 their full growth. If weather conditions are at all favorable after a good 

 Tainfall in late .summer or early autumn, the rust mav spread rai)idlv. 



FIG. 73. METHOD OF 



TREATMENT. 



