Vegetable and Field Crops 191 



Two Cercospora leaf-spots also occur on cucumber and 

 watermelon, and two Septoria leaf-spots on cucurlnts gen- 

 erally. 



Leaf -glaze -^^ {Acremonium sp.). — Shoots are stunted, 

 fruits deformed, and leaves yellowed and killed. Upon the 

 lower leaf surfaces a delicate white, glossy film like dried 

 albumen is seen. Plants that are attacked ma}^ put forth 

 new, vigorous shoots to survive for a time;, then die. The 

 disease has been known to reduce the jaeld 90 per cent. No 

 treatment has been advocated. 



Blossom-rot (Rhizopus nigricans Ehr., Choanephora cucur- 

 hitarum (B. & Rav.) Thaxt.) spreads to the young squash, 

 cucumber, or pumpkin, causing loss of the fruit })y soft- 

 rot. 



Root-knot (nematodes). Of the cucurliits, the watermelon 

 is very susceptible. Root-rot due to Thielavia is somewhat 

 injurious. 



Cucurbit Spraying -^'* 



Planting should be at such distance as to facilitate ma- 

 chine spraying; that is, relatively close in the row, but with 

 the rows wider apart than is usual in most sections of the 

 country. In cultivating, the vines should be induced to 

 spread along the row, and by the use of a vine turner a 

 one-foot open alley may be maintained throughout the season 

 for the wheels of the sprayer. 



By means of a geared sprayer with proper length of axle 

 to cover one row, three rows may be sprayed at one time. 

 Particular attention must be given to reaching the under sides 

 of the leaves with the spray. Spray first when the vines begin 

 to run, using 3-6-50 Bordeaux mixture. For subsequent 

 sprayings use 4-4-50 Bordeaux mixture at intervals of about 

 ten days if the weather is drj^; oft oner, if growth is rapid. 

 The net profits from this treatment have been as high as 

 $163.50 an acre. 



