548 STATE HORTICULTURAL SOCIETY. 



Any disease that destroys the foliage of our trees and vines virtually destroys the* 

 fruit and reduces the vitality of the tree and vine so as to enfeeble the same for the? 

 succeeding crop. 



Dusting with sulphur and lime has been practiced for years with more or less success s> 

 but now spraying with the copper carbonates and ammonia is the remedy, or rather the 

 preventive, for every species of fungi, whether on the foliage or on the fruit. The foli- 

 age of many other fruit trees is also affected by this fungi. The cracking of the pear is a 

 fungus affection. The pear scab and the apple scab are caused by a microscopic vege- 

 table fungi. This fungi, like every other species, is a vegetable parasite and feeds upon 

 the juices of its host whatever that may be. The effects of this fungi are too apparent. 

 to the common observer to require any particular delineation here. The fruit thus; 

 affected is inferior in size and quality, being one-sided, as the fungi usually attacks one> 

 side, while the other side develops in its natural order. The Sekel pear is par- 

 ticularly subject to this fungi, and being small is often rendered nearly worthless there- 

 by. Last year the Flemish Beauty was badly affected in the foliage by the fungi' 

 known as the rust leaf blight and shed its leaves prematurely. The fruit, too, what little* 

 there was, was generally cracked. 



Some of the diseases that affect our trees are of such a mysterious character that w©> 

 know neither the cause, the remedy, nor the preventive. Among these the peach yellows; 

 has baffled the ingenuity of man for a hundred years or more. It is as a dark mystery 

 now as ever. One peculiarity of this disease is tb at the fruit is affected to all appear- 

 ance simultaneously with the tree. The fruit generally shows the first symptoms of the- 

 disease by the discoloration of the skin and flesh, a spongy, often abnormal growth, andi 

 insipid flavor. These symptoms of disease not unfrequently occur in the fruit, while the> 

 tree has every appearance of a healthy, vigorous vitality. This is probably one of the- 

 incipient stages of the disease. The subsequent stages are manifested in the general sickly- 

 appearance of the tree, the yellow cast of the leaves, the want of vitality, and the 6malll 

 wiry shoots emanating from the branches and twigs of the tree. Another peculiar 

 characteristic of this disease is, an attack of a tree in ever so mild or minute a form 

 indicates the certain destruction of the tree. The affected fruit is insipid and worth- 

 less, and the life of the tree is only a question of two or three years at most. What- 

 ever the cause may be, whether it is microbe, bacteria, or parasitic fungi, or whatever- 

 else, the only recommendation that can be made is to remove the tree as soon as th6* 

 disease manifests itself (either in the fruit or the wood), root and branch, and destroy it. 

 by fire. By a microscopic examination of the roots of many diseased trees in Delaware* 

 a year or two ago by Mr. Smith, of the agricultural department at Washington, no indi- 

 cation of disease was found in the roots. They were to all appearance healthy. 

 Whether science, art, or skill will ever divulge the cause, the remedy, or the preventive., 

 is for the future to determine. 



The plum and cherry trees are subject to disease known as the black-knot — the pluns 

 more so than the cherry and is affected more by it. This is doubtless caused by a. 

 fungus parasite that feeds upon the tender tissues of the wood and grows in knots and! 

 bulges on the body or limbs of the tree. It makes an unsightly appearance, and if" 

 allowed to run its course unchecked, will in a short time destroy the tree or render it 

 worthless. No effectual remedy or preventive has yet been discovered. When trees; 

 are hopelessly affected the better way is to remove them root and top and burn them. 

 When not too much affected the diseased parts may be pared off, cut out, and burned^ 

 and the wound coated over with linseed oil or a mixture of linseed and kerosene oils. 



The fruit of both the plum and the cherry is subject to the fungus disease known as; 

 black rot, similar to the black rot on the grape. This and the fungoid leaf rust, so* 

 fatal to the plum, may at least partly be prevented by the timely application of the* 

 copper carbonate and ammonia fungicide. To be effectual for the plum this applica- 

 aion should be made early, as soon as the foliage is ready to open, and every three' 

 weeks thereafter. Fungoid spores are maturing and are disseminated from tree tc tree? 

 through the summer. The black-knot does not affect the fruit, only as it affects the- 

 vitality and vigor of the tree. As the plum will require about the same number of 

 applications of the fungicide as of the insecticide, the two may be mixed and applied! 

 at the same time, thus destroying the curculio and preventing the rot. If these two 

 enemies of the plum and cherry, curculio and rot, can be successfully combatted, I see* 

 no reason why these fruits can not be profitably grown any where in this country. 



The grape is subject to various diseases, among which the downy and powdery mil 1 - 

 dew and the black rot are conspicuous. These are all of the fungoid family, and where> 

 they largely prevail a preventive must be applied in order to save the crop, as a remedy 

 or cure is out of the question. When the fungus spores have once established them- 

 selves on the fruit no application can remove them. As this fungi may, and probably 

 will, attack the foliage before the fruit is set on the vines, it will be necessary to apply 

 the fungicide as soon as the leaf buds are fairly formed, again when in full leaf, andi 

 again when in bloom or shortly after, and once or twice after the fruit has 6et. Thfe 



