440 THE MONTHLY BULLETIN. 



to contribute to this meeting that would be of interest to the fruit 

 growers of California. At the suggestion of Mr. Cook, however, that I 

 discuss some phase of eastern orchard management or experimental 

 work, I wish briefly to outline the results of some spraying experiments 

 conducted in Maine apple orchards for the past two years. 



The time has long passed M'hen the necessity and value of spraying 

 for the control of insect and fungus enemies of deciduous orchard fruits 

 has to be proved. In the large regions devoted to fruit growing in the 

 Middle, Central and Pacific Coast states spraying has long been an 

 accepted part of the annual orchard treatment by all men who look to 

 their fruit for an important source of their revenue from the land, and 

 rightly so, for every year has shown them that spraying properly done 

 means healthier trees, cleaner and better fruit, and, in consequence, 

 better returns. 



Spraying in its extension has also brought with it problems for solu- 

 tion. For many years Bordeaux mixture has been the standard fungi- 

 cide for orchard spraying, with Paris green or arsenate of lead used in 

 combination with it as the insecticide. Paris green has in recent years 

 been largely superseded by arsenate of lead, because the former has a 

 great tendency to burn and injure foliage, whereas lead arsenate has been 

 found equally effective in destroying leaf-eating insects without the 

 injurious effects upon the leaves. The increasing use of Bordeaux mix- 

 ture has, however, been accompanied by reports of injury to fruit and 

 foliage. Such injury appears to vary in degree and in different sea- 

 sons. It has long been known that Bordeaux cannot be used with 

 safety on the peach and the Japanese plum when the tree is in leaf. 

 On the apple and the pear the injuries have manifested themselves in 

 two ways — burning and spotting of the leaves and russeting and cork- 

 ing of the fruit. The leaves so affected show dead brown spots similar 

 in general appearance to some fungus leaf spots, generally roundish or 

 circular, but often irregular. Frequently the areas are large, as though 

 a number of smaller ones had united. Occasionally the margins of the 

 leaves show the characteristic dead blackened areas. Such foliage injury 

 is very frequently followed later in the season by yellowing and pre- 

 mature leaf -fall. This occurs early or late in the growing season accord- 

 ing to the severity of the injury. Sometimes it does not occur at all. 

 Whether such yellowing is actually the result of Bordeaux spraying is a 

 mooted point among investigators, but it is an acknowledged fact that it 

 is frequently an accompaniment of leaf injury from this source. 



On the fruit the injury is first seen as small, dark, flyspeck-like spots. 

 These are not to be confused, however, with the spot of the scab fimg'us. 

 The final appearance of the fruit may be well known to some of you. 

 The skin is washed with a rusty or russeted coat which materially 

 detracts from its appearance. In more severe cases the apple has been 

 stunted in growth and has suffered malformation, while the russeted sur- 

 face may be greatly roughened or even corrugated. In very severe 

 cases the skin may crack and show V-shaped splits on the surface of 

 the fruit. 



