Bordeaux Spraying for Melon Blight. 273 



otherwise much trouble will occur from the clogging of pumps, hose, nozzles, etc. 

 The cost of treating San Jose scale with the lime-sulphur mixture will de- 

 pend largely upon the number of trees to be sprayed. Where only a few trees 

 are to be treated, the mixture may be made in a large iron kettle ; but in any 

 case a good spray pump, rubber hose connections, and nozzles are essential to 

 good work. In a community where several small infested places are close 

 together, much expense may be saved by co-operation, one boiling and spraying 

 apparatus being sufficient for several places. 



BORDEAUX SPRAYING FOR MELON BLIGHT. 



By E. R. Benxbtt, Assistant Horticulturist Storrs Agricultural Experiment Sta- 

 tion, Storrs, Connecticut. 



Cucumber and melon growing have been practically driven from this State 

 by the diesease known as melon blight {Plasmopara ctibcnsis). Another disease 

 of melons and cucumbers, the bacterial wilt, has done some damage in different 

 parts of the State, but, as compared with the bliglit. it is at present of little 

 consequence. These two diseases are frequently confused, tliough the appearance 

 of each is distinctive. When the bacterial wilt attacks a vine, the leaves wilt 

 as though the vine had been severed from the root. The leaves nearest the root 

 wilt first, then the disease quickly follows along to the tip of the vine, and the 

 plant dies. Melon blight first appears as irregular yellow or greenish spots that 

 soon become dry. These appear on the older leaves first, but do not cause the 

 leaf to wilt. The bacterial wilt is caused by a bacterium and is supposed to get 

 started in the plant from inoculation by insects. All vines attacked in this 

 way should be immediately removed and burned. 



WHAT THE MELON BLIGHT IS. 



This disease is caused by a parasitic fungus. It is transferred from one 

 plant to another by spores, minute seed-like bodies, that are blown about by the 

 wind like dust. These settle on the leaves of the host plant, germinate, and send 

 out a root-like thread, that enters through the pores of the skin into the tissue 

 of the leaf. When the fungus has reached a certain stage of development in 

 the leaf, it sends out fruit organs on the under side of the leaf, giving the spot 

 the downy appearance from which the disease takes its name (downy mildew). 

 This fact, that the disease starts from the upper surface of the leaf, gives us 

 a suggestion as to its proper treatment. 



BORDEAUX AS A REMEDY FOR MELON BLIGHT. 



An experiment to determine the effect of Bordeaux mixture as a remedy for 

 the disease was made during the past season. Two plots of cucumbers of 

 twenty-four hills each were planted June 18th. Owing to the extreme wet, cold 

 weather which followed, most of the seeds of this planting rotted in the ground. 

 Re-planting was done June 29th. From the second planting a good stand of 

 plants was secured. Striped beetles attacked the plants as soon as they were 

 out of the ground, but were held in check by a liberal use of ground tobacco 

 stems. Clean cultivation was given the plants throughout the season. Bol)^ 

 plots were thinned to four plants to each hill as soon as the danger from insects 

 had passed. 



HOR. 18 



