Page 34 



BETTER FRUIT 



February 



SPRAYING IN ONE OF THE MANY BEAUTIFUL ORCHARDS IN 

 WENATCHEE VALLEY, WASHINGTON 



trying to control, and they were, there- 

 fore, compelled to exercise their ingenu- 

 ity in an attempt to find a remedy; and. 

 indeed, some of the svipposed remedies 

 employed during the sixteen and seven- 

 teen hundreds were very ingenious. 



Among the great array of common 

 substances early experimented with it 

 would be strange if some Araluable rem- 

 edy had not been found; and thus, in 

 1821, sulphur was recommended in Eng- 

 land for peach mildew, and sulphur is 

 today probably our best fungicide for 

 that class of diseases called mildews. 

 As early as 1833 we find what is essen- 

 tially a weak lime-sulphur solution rec- 

 ommended in this country for mildews. 

 Up to 1880, however, no very satisfactory 

 remedies were in use for the fungous 

 diseases, with the exception, perhaps, of 

 sulphur in various forms, as mentioned 

 for midews. About 1880 a more or less 

 systematic search for substances having 

 fungicidal properties was taken up by 

 French investigators, and the matter was 

 soon sifted down to the employment of 

 copper compounds; and of various classes 

 of substances so far tested copper com- 

 pounds still remain as the most gener- 

 ally potent fungicides. In 1882 the value 

 of bordeaux mixture, made by combining 

 lime and blue stone or copper sulphate, 

 was discovered by accident in France, 

 and it proved to be such a generally val- 

 uable remedy and stimulated such an 

 array of investigations of plant diseases 

 that we may say the serious study of the 

 subject of plant disease control began 

 about that time — twenty-five or thirty 

 years ago. 



Within a few years after the discovery 

 of bordeaux the treatment of plant dis- 

 eases began to receive attention in this 

 country. Black rot of the grape, that 

 was causing trouble in France, was like- 

 wise damaging the crops in the Eastern 

 states, and in 1885 the Federal Depart- 

 ment of Agriculture published its first 

 two circulars on fungous diseases. They 

 dealt with the treatment of downy mildew 

 and black rot of grapes. Up to 1890 less 

 than a dozen different plant diseases had 

 received the attention of the Federal 



Department of Agriculture. The work 

 had hardly commenced. Within recent 

 years, however, the combined efforts of 

 the various state experiment stations 

 and of the federal department has pro- 

 duced a remarkable array of work, and 

 we may feel assured that no European 

 country has made anything like the 

 showing we have in the practical control 

 of horticultural pests. 



To illustrate, the Ohio Experiment 

 Station has recently issued a bulletin 

 called "A Brief Hand Book of the Dis- 

 eases of Cultivated Plants in Ohio." In 

 it are briefly discussed over four hundred 

 different diseases, practically all of which 

 occur in that state, and nearly all are of 

 fungus origin. The apple claims twenty- 

 four of these, the peach eighteen and the 

 pear ten. 



Some of these Eastern troubles will 

 no doubt reach the Pacific Coast in time, 

 but many of them that are of serious 

 consequence there will not cause by any 



means the same amount of damage hi 

 California. Brown rot, for instance, is 

 capable of destroying seventy-five per 

 cent of the peach crop in Georgia in less 

 than a week if a series of damp, warm 

 days come at about the pickint;- time. 

 Brown rot exists in California, but it will 

 never become a serious pest of stone 

 fruits because the dry summer weather 

 will not allow it to develop. On the 

 other hand, the apple powdery mildew 

 seems to find the environment of the 

 arid West more conducive to its develop- 

 ment than are the conditions east of 

 the Rocky Mountains. Other examples 

 might be cited of the relative severity of 

 a given disease in dif¥erent localities. 



Considering some of the fruit diseases 

 of this state, let us review briefly our 

 knowledge of the commoner ones, and 

 their methods of control. 



One disease that is common to a large 

 number of fruits is root rot. Peaches, 

 apricots, almonds and apples are fre- 

 f|uently destroyed by this malady. Some 

 blocks of apples in this valley have been 

 very seriously attacked. When a tree 

 is once affected it is almost sure to go 

 sooner or later. As mentioned before, 

 the usual type of root rot found in Cali- 

 fornia is caused by a form commonly 

 called the oak tree fungus, nr toadstool 

 fungus, and many orchardists recall oak 

 trees standing in the locality where trees 

 have since died out in their orchards. 

 The fungus is one of the toadstool group, 

 and in damp springs large patches of 

 toadstools are frequently seen coming up 

 around the base of a tree that is being 

 rapidly killed. The disease may be 

 quite easily recognized on examining the 

 crown and roots of the tree, for if the 

 root rot is present it can be detected by 

 the white fibrous layer of fungus threads, 

 or mycelium, as it is called, occupying 

 the region of the cambium layer, just 

 between the bark and the wood. Some- 

 times the outer surface of the roots is 

 flecked here and there with, bits of the 

 white mycelium. The inner bark dies 



