LOSSES DUE TO CROWN-GALL. 185 



Tourney wrote: 



In California, where the fruit industry is many times what it is in Arizona, the 

 losses must be correspondingly great. 



In Pennsylvania on fruit trees in the nursery, according to Butz 

 (Ann. Rep. Pa. State College, 1902, p. 405): 



There is little warning of the presence of the disease in a block of trees while they 

 are developing into salable stock, but when they are taken up it is frequently dis- 

 covered that from 20 per cent to 80 per cent of them are affected at the roots with crown- 

 gall, rendering them unsalable. 



Butz also cites from correspondents as follows: 



We have known peach blocks in New Jersey to be entirely destroyed. * * * One 

 year ago we had it bad in peach and threw away thousands. 



APPLE TREES. 



Wliitten, of Missouri, reported to Tourney as follows: 



I have seen it on a few apple trees in the nursery, but it was not severe enough to 

 impair their growth. 



Concerning the injury done to orchard trees, Butz has the fol- 

 lowing as the result of one of his experiments. 



On November 21, 1898, 11 apple trees were planted upon the station grounds. 

 These trees were donated by a Pennsylvania nurseryman, and all of them bore galls 

 at the crown varying in size from a hickory nut to an unhulled walnut. The root 

 system of these trees was apparently most excellent, having an unusual amount of 

 fibrous roots. But owing to the fact that these fibrous roots proceeded mainly from 

 and about the galls it was evident that the galls were the inciting cause of the unnatural 

 development. The trees were three years from the graft, and but for the galls were 

 excellent trees for planting in the orchard. Five of these trees were York Imperial 

 and six were Ben Davis, the two varieties of apple which are most susceptible to crown- 

 gall and the most extensively propagated and planted in Pennsylvania. Records 

 taken in April, 1901, after the trees had made two seasons' growth, show immediate 

 injury due to the galls. Two trees of York Imperial had died, and the other three 

 had made only weak and slender growth. * * * 



Of the Ben Davis trees, all grew, though the growth made was in all cases short and 

 weak. The length of the best shoots made in the second season varied from 4 to 10 

 inches. After another year's growth these trees are still living, making some new 

 wood each year, though it is not as strong as it should be. An examination of the galls 

 at the roots (June, 1902) by removing the ground about them shows that they are 

 increasing in size, and in some cases more completely girdling the trees than when they 

 were planted. The effect of this gall development is shown in the heavy production 

 of sprouts from the stock roots below the gall and the consequent weakness in the 

 graft head. * * * 



A peach grower in Franklin County in Pennsylvania is now having a similar expe- 

 rience with peaches. He wrote me in November, 1900, that he suspected something 

 wrong with a block of 1,000 peach trees in an 80-acre orchard, and digging at the roots 

 discovered an enlargement which was identified at this station as crown gall. The 

 trees came from an Alabama nursery and were planted in the spring of 1899. The 

 growth during the first two years was excellent, but now as the trees reach fruiting 

 age they indicate a weakness that can not be overcome. 

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