278 STATE BOARD OF AGRICULTURE. 



When stable manure is used for fertilizer, every precaution should be taken 

 to keep Infected cabbage refuse from getting into the manure for in this way 

 the whole heap will become infected with the rot germs and when it is spread 

 on the field the entire plat will become inoculated. One of the worst plant dis- 

 ease epidemics on record was caused in this very way. The writer refers to the 

 present watermelon wilt in North Carolina, South Carolina and Georgia, where 

 melon growing for the past two years has been practically abandoned by the 

 smaller producers because of the ravages of the wilt. The only safe way to 

 dispose of refuse is to burn it. 



It has been demonstrated experimentally by Harding,* Stewart and Prucha 

 that the cabbage seed itself is contaminated with the black rot germs, that some 

 of them could live over winter on the seed and become the source of infection 

 to the young cabbage plants. They advise disinfecting the seed before sowing 

 by soaking it in a 1-1000 solution of corrosive sublimatef for fifteen minutes 

 or in formalin, one pound in thirty gallons. 



The removal of sick leaves in the early stages of the disease is practiced by 

 some growers with success. Others have tried this preventative and found it 

 to be a complete failure. The recent investigations of StewartJ and Harding 

 condemn this practice and prove quite conclusively that the method is not only 

 harmful to the plants but also worthless. The treatment fails, they say. because 

 "The removal of so many leaves checks the growth of the plants; in- 

 fection occurs by way of the roots as well as through the leaves; infec- 

 tion may occur at the base of the leaf close to the stem and get into 

 the stem unobserved; the germs of the disease are so widely and so 

 abundantly distributed that it is useless to try to stamp out the disease 

 by the removal of the diseased material." 

 Warm days, cool nights, and frequent showers seem to accelerate the rot. 

 Smith§ is inclined to think that cabbage planted late is less susceptible than that 

 which is planted early. In selecting cabbages for producing seed the following 

 season, care should be taken to pick out only those which are absolutely free 

 from the infection. 



When cabbage is to be stored over winter, the heads should be examined 

 critically and any diseased ones rejected or kept by themselves. The room or 

 store house must be kept cool, below 40° F., and must have uniform ventilation. 

 It is a matter of common observation that when cabbage is grown year after 

 year on the same piece of land, there is a notable increase in the amount of rot. 

 In the first place, such a method is not to be recommended from an agricultural 

 standpoint since it violates the important principle of crop rotation and further, 

 if it becomes necessary, because of limited space, to continue using this land, our 

 only hope of getting rid of the disease is to grow crops other than members of the 

 cabbage family for five or ten years and longer. During this interim the 

 land must be kept free from all cruciferous weeds which harbor the bacteria, 

 especially from the common wild mustard. 



If possible, cabbage should be set each year on ground which has not been 

 planted to it for some time or which has been in sod several seasons or else 

 cultivated to crops which are not affected by the rot. The one important thing 

 for the gardner to observe if he would be a successful cabbage grower, is to 

 take the utmost care to keep his field from becoming infected, and if once infected 

 not to spread the malady over his whole farm. 



WILT OF THE CUCUMBER, MUSKMELLON AND SQUASH. 



This disease of the Cucurbits does the most damage early in the season when 

 the vines are just beginning to run. Sometimes, however, seedlings succumb 

 to the infection while again the wilt does not appear until the vine is in full 

 bearing. Such an instance was observed in the cucumber forcing house at the 

 college this spring. The vine was apparently healthy and doing well when sud- 

 denly the leaves began to wilt as if from lack of water or too much hot sun. 



* Bulletin 251. N. Y. Exp. Sta. 



t Corrosive sublimate. 1 part: hydrochloric acid, 2 parts; water, 1000 parts. 



i Bulletin 232, N. Y. Exp. Sta. (1903). 



{ Loc. Cit. pp. 12. 



