188 CROWN-GALL OF PLANTS. 



THE QUINCE. 



The galls of the quince (Cydonia vulgaris) occur on the stems, and 

 are warty in appearance. Often an entire limb will be covered by 

 these broad irregular outgrowths. Whole orchards in California 

 have been attacked by these galls and quince trees in other western 

 States are known to be affected. Mr. Hedgcock has received dis- 

 eased specimens also from Ansted, W. Va. Doctor Trabut sent speci- 

 mens of quince gall from North Africa (PL XXXV). Lounsbury 

 reports a quince gall which appears in the form of "rough, lumpy 

 growths" as common in South Africa. 



THE RASPBERRY AND THE BLACKBERRY. 



The disease appears to be quite prevalent on the red raspberry in 

 various places in the United States, and must be regarded as injurious, 

 although some nurserymen are of a contrary opinion. The extent of 

 injury to black raspberry and to the blackberry is not kno^vn. Mr. 

 P. J. O'Gara has observed one apple and pear nursery in Oregon 

 where practically all of the young trees were galled. This nursery 

 was set on the site of an old berry patch in which the cro\vn-gall had 

 prevailed (verbal communication). 



The following similar statement is taken from the report of the 



Dominion Botanist (Giissow) (1 George V, Sessional Paper No. 16, 



A. 1911, p. 273): 



One prominent grower had a small area planted with raspberries. These on being 

 taken up showed many "root galls." The plants were destroyed and no specimens 

 were sent us for examination. The grower then planted a large area to young peach 

 trees, the rows of which passed through the land formerly occupied by the raspberries 

 on which the root galls were discovered. He then observed that the peaches grow- 

 ing on this latter area were not doing well and finally failed, while all the other trees 

 did exceedingly well. On taking up the failing peach trees, their roots showed plenty 

 of root galls, while the others growing outside the raspberry area were free from it. 

 The same facts were recorded by other growers. There could hardly be given a 

 more typical example of an infectious disease. But, unfortunately, we were not 

 acquainted with any of these observations until it was too late to make any investi- 

 gation. If these facts as related are correct, and we have no reason to doubt them, 

 there is still a considerable amount of research necessary. 



Selby is on record as long ago as 1 898 to the same effect. He says 

 that 16 per cent of some healthy peach trees planted in a badly 

 galled raspberry plantation became affected with the gall. 



Wulff's statements (Studien tiber heteroplastische Gewebewuche- 

 rungen am Himbeer- und am Stachelbeerstrauch, Arkiv f iir Botanik, 

 Bd. 7, No. 14, Upsala, 1908) are equally explicit. He says respecting 

 the appearance of the raspberry gall in a garden near Karlshamn 

 (South Sweden) : 



On an area of 33 by 4 paces were about 100 raspberry bushes, all very badly affected 

 by the disease. * * * From the time of their planting in 1901 to the summer of 

 213 



