200 The Sugar-Beet in America 
comes black and crisp. The outer, or older, leaves are 
the ones first affected. 
Townsend,! in summarizing methods of control, says: 
“(1) Leaf-spot may be controlled on a commercial scale 
and in an expensive manner by a carefully planned and 
thoroughly executed system of crop rotations or by deep 
fall plowing. The best results are obtained by combin- 
ing these two methods. 
“(2) A proper and uniform supply of soil moisture, 
spraying, and proper disposition of beet tops and stable 
manure are important aids in the control of the leaf-spot. 
“(3) The principal agencies in the distribution of the 
leaf-spot fungus are wind, water, insects, and man and 
other animals. 
“(4) Leaf-spot tends to reduce either the tonnage or 
the sugar content of the beet, or both, depending on the 
time, duration, and severity of the attack. 
“(5) Leaf-spot seriously injures the feeding value of 
beet tops.” 
Bordeaux mixture is used as a spray. The fungi are 
killed when the beet tops are siloed. 
Heart-rot (Phoma betae Frank). 
This disease, which is one of the most serious of the 
sugar-beet in sections of Germany, Austria, and France, 
has recently been introduced into the United States where 
it will probably become rather serious in the next few 
years. It has already gained a strong foothold in several 
beet-growing sections. 
1 Townsend, C. 0., U. S. Dept. of Agr., Farmers’ Bul. No. 618 
(1914). 
