190 CROWN-GALL OF PLANTS. 



energy used up in the production of the galls, which are often large, 

 must be abstracted from the general needs of the plant, which as a 

 result must either yield an inferior product or blossom for a shorter 

 period. 



The following statements were received in 1909-10 from a rose 

 grower who had much of the gall in his houses : 



Our houses of 10,000 plants seem all to be affected, and it looks [October 23] as 

 though we would have to throw the plants out. 



The disease was definitely identified as crown-gall by the writers, 

 who received numerous well-developed specimens (PI. XX, fig. 2) 

 and recommended substitute crops. Nematodes were not observed. 

 This man was asked later in the season for more definite information 

 concerning his losses and replied as follows : 



Replying [February 22] to yours of 16th instant, would say that after consultation 

 with other growers of roses who had had experience with crown-gall and eel worm, we 

 decided to keep our plants in and get what we could from them, rather than take a 

 chance on some other crop so late in the reason. 



AH the plants are affected more or less — some not as bad as others — while perhaps 

 200 or 300 have been killed outright. 



The great loss is shown when we come to cut the buds. At a time when we should 

 have been cutting 1,500 to 2,200 a day, we were cutting but from 400 to 600, and the 

 average loss for the season thus far has been on a conservative estimate 67 per cent. 



We will cook our soil this year and hope for better results another season. 



In December, 1910, this grower wrote as follows: 



Replying to yours of 9th instant, would say we did cook our soil last spring, as we 

 wrote you we should, and that we have had no trouble with crown-gall this season. 



Our plants are very fine this year, and we have been cutting some very fine blooms. 

 Just now we are off crop, but plants are breaking in good shape and the future looks 

 very promising. 



Our commission house sent us word early in the winter that they had not seen finer 

 specimens of Bride outside of the nower show than the ones we were shipping. 



THE GRAPE. 



European observers have generally regarded the scab of the grape 

 as a serious disease. 



Delacroix (1908) states that the attacked shoots grow feebly for a 

 year or two and then the parts above the galls dry out and die. 



The statement of Cavara respecting rachitic growth has already 

 been quoted (p. 15). 



In Italy, in 1906, in the Po Valley (near Modena), the senior writer 

 saw cases of rogna on large vines and was informed by competent 

 viticulturists that the disease was becoming more and more prevalent, 

 mostly on the flat irrigated lands, but to some extent also in the hills, 

 and that the life of an attacked vine seldom extended beyond four 

 years. In sections of Italian rogna of the grape preserved in 10 per 



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