PEACH 



PEACH 



1231 



appear late in autumn, after the leaves have fallen, or 

 in spring before normal growth begins. They are often 

 first seen upon the ends of waters prouts. This "tip" 

 growth is sometimes little pronounced, and then only a 

 practiced eye will detect 

 it. The third mark of 

 the disease is the push- 

 ing out of slender stiff- 

 leaved yellowish shoots 

 from the body of the 

 tree or the sides of the 

 large limbs (Fig. 1676). 

 In pronounced cases, or 

 when the tree is about 

 to die, these shoots may 

 branch into close bunchy 

 tufts. These symp- 

 toms are frequently 

 wholly absent in this 

 1667. state throughout the en- 



The Michigan vase-form tree. 



-;;=* 



dis- 



tire course of the 



ease. 



In its final stage, the yellows is marked by small and 

 slender growth of all new wood, small, narrow, yellow 

 or reddish foliage, and occasionally by a great pro- 

 fusion of slender and branchy growths in the center of 

 the tree. As a rule, yellows trees die in five or six 

 years from the first visible attack, sometimes sooner. 

 The yellow and stunted condition following neglect or 

 the work of borers both of the common borer and the 

 pin-hole borer is often mistaken for yellows. Ex- 

 termination of all affected trees root and branch is 

 the only method of keeping the disease at bay. This 

 work should be done vigorously and thoroughly. The 

 entire community should unite. Trees may be set in 

 the places from which the diseased trees are removed, 

 without fear of contamination. The cause of the disease 

 is wholly unknown. Almost every ascribed cause has 

 been disproved upon careful investigation. Even when 

 the cause shall have been discovered, the remedy will 

 probably remain the same extermination. The disease 

 has no uniform preference tor varieties, soils, climate, 

 nor methods of propagation or cultivation. No fertiliza- 

 tion of the soil will cure the disease or check its spread. 

 The disease sometimes attacks the almond, apricot, and 

 Japanese plum. Yellows has been recognized for 

 about a century. It is peculiar to North America, and 

 is generally distributed north of the Carolinas and east 

 of the Mississippi. For more specific information on 

 Peach yellows, consult the writings of E. F. Smith, 

 published by the U. S. Dept. of Agric. 



Rosette is a very serious disease of Peach trees in 

 the southern states, characterized by dense rosettes 

 or bunches of foliage on the young shoots. It soon 



1668. Peach trees in Eastern Maryland. 



proves fatal. The cause is unknown. The remedy is 

 to exterminate the trees as soon as the disease appears. 

 The leaf curl has been the subject of more concern 

 amongst Peach-growers during the past few years than 

 any other disease, except the yellows. It has a decided 



preference for some varieties, particularly those with 

 large, soft arid dark-colored leaves. It is also influ- 

 enced greatly by the season, although it is rarely wholly 

 absent. A moderate attack does not perceptibly injure 

 trees in full vigor. In many cases, however, the 

 larger part of the leaves fall from the tree in June, and 

 the fruit, deprived of nourishment, may also fall. Leaf 

 curl, the curculio and lack of pollination are the chief 

 causes of the "June drop" of Peaches. The leaves 

 "curl," or become puckered, early in the season, and 

 soon die. Experiments have demonstrated that a thor- 

 ough spraying with full-strength Bordeaux mixture just 

 before the buds swell in spring is very nearly a spe- 

 cific. If long-continued wet weather follows, it may be 

 advisable to spray again, when the petals have fallen, 

 with Bordeaux mixture, consisting of 2 pounds of cop- 

 per sulfate, 2 pounds of quick-lime, and 50 gallons of 

 water. If the weather of April and early May is warm 

 and dry, this second spraying will be unnecessary. For 

 full account of Peach curl, see Newton B. Pierce, Bull. 

 20, Div. Veg. Phys. and Path., U. S. Dept. Agric., 1900 

 (pp. 204). 



" Little Peach " is a recent disease which has appeared 

 in Michigan and western New York. It is ordinarily 

 characterized by the Peaches remaining small and hard, 

 the trees losing vigor and the leaves becoming small. 

 After a time the tree dies. It seems to spread when 

 once established in an orchard. The cause of the diffi- 



1669. View in a young Michigan Peach orchard. 



culty is quite unknown. By some it is thought to be 

 due to a root fungus. Others have associated it with 

 dry seasons, the lack of fertility in the soil, overbearing 

 and other exhausting processes. It has every appear- 

 ance, however, of being a distinct disease. No remedy 

 is yet known. Growers are advised to pull out the trees 

 and burn them as if they had yellows. Some growers 

 think that they can overcome the disease partially or 

 wholly by liberal applications of nitrogenous fertilizers 

 and by extra attention to tillage. All these questions, 

 however, yet remain to be demonstrated. 



Fruit-rot and twig-blight, due to the fungus Manilla 

 fructlgena, is a serious disease of Peaches. The rot- 

 ting of the early Peaches on the tree is too familiar to 

 need description, but it is not generally known that this 

 decay is not a normal process and peculiar to the va- 

 riety, but is caused by a distinct fungous disorder. 

 Very often these same trees that show the fruit-rot have 

 the young growth blighted, as if attacked by something 

 like pear-blight. This death of the shoots is due to the 

 same fungus that causes the fruit to rot. The decayed 

 Peaches sometimes dry up and hang on the tree, and be- 

 come a prolific source of infection for the coming year. 

 These mummified Peaches can be found in orchards all 

 over the country, even, in many cases, a year following 

 the attack. They are likely to be most abundant in the 

 center of the top,and the fungus often kills the twigs that 

 bear the diseased fruits. The same fungus attacks the 

 cherry and plum. Prof. F. D. Chester, of the Delaware 

 Experiment Station, found that the fungus sometimes 

 destroys the flowers in spring, and this injury may 

 pass for the effects of frost. He also found that thor- 

 ough spraying with copper fungicides greatly reduced 

 the injury. His advice for the treatment of the dis- 

 ease is as follows: (1) Gather and burn all mummified 

 fruit. (2) Early in the spring, before the fruit-bud* 



