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Wilt 

 Caused by Fusariuyn sp. 



Sweet potato wilt, known also as stem-rot, is caused by a species of 

 Fusarium which grows within the plant, killing and rotting the roots 

 and causing the wilting and death of the tops. 



It is known to occur in 8 Illinois counties, rather widely separated, 

 as shown on Map 104. Three of the S counties have important commer- 

 cial acreages. Where the disease has been seen it has been severe in the 

 extreme. The loss in Cass county, on the Nancy Hall variety, ranged 

 from 5 to 10 per cent, in two Union county fields from 5 to 10 per cent, 

 and elsewhere from 1 to 10 per cent. 



Control involves the use of healthy seed, clean soil in the seed-bed, 

 and a consistent rotation of crops on infected land. 



Cantaloupe 



During the years 1918-1921 the commercial cantaloupe acreage in 

 Illinois varied from 865 to 880 acres, the state ranking 14th in acreage 

 of this crop. The yield per acre varied from 142 to 200 standard crates 

 of 45 melons each, and the total yield varied from 35G cars (3.j0 crates 

 per car) in 1918 to 505 cars in 1921. 



In addition to this commercial crop there is probably an equal pro- 

 duction by local growers who supply the small-town seasonal markets. 



The commercial production of cantaloupes, while carried on more 

 or less generally over the state, is usually confined locally to a relatively 

 small area, where suitable soil conditions exist. 



Diseases of the cantaloupe, while not numerous, may often be severe. 



Wilt 

 Caused by Bacillus tracheiphilus E. F. S. 



Wilt is a bacterial disease which causes the vine to wilt and die. It 

 has probably been present in Illinois for years but it has not been often 

 reported. Burrill found it in Union county in 1918, and it was seen in 

 1923 in the Poag Station melon-district in Madison county, and was 

 more widely observed in 1933. 



At present it is known to occur on cantaloupe and nuiskmelon in 

 18 counties, the distribution of which is shown on Map 105. It appears 

 wide-spread in the state, with none of the larger areas of production 

 free from it. 



Losses due to it as observed in the field during 1923 especially, 

 varied usually from 1 to 1 per cent : more rarely, from 20 to 30 per 

 cent. 



Control is obtained by pulling and burning diseased plants, by crop 

 rotation, and by ."ipraying to prevent its spread by insects. 



