4U CORN-SMUT. LEAF-SMUT OF TIMOTHY. 



tive medicinal iind poisonous properties, uid it bus been demon- 

 strated tbat abortion and certain diseases of tlie feet of cattle fol- 

 low tbe prolonged use of ergotized bay or pasturage. How many 

 of tbe smuts and otber fungi of grasses possess similar or otber 

 detrimental properties is at present merely a matter of conjec- 

 ture; but some of tbem occur in sufficient quantity to merit sus- 

 picion until tbey have been shown to be harmless. Students will 

 find the principal parasites of grasses represented by actual speci- 

 mens in fascicle 2 of Seymour and Earle's Economic Fungi, Cam- 

 bridge, Mass., 1891. 



SMUTS. 



1. V 'X-smut {Ustilago ze(B mays, B.C.). Forming galls, of ten 

 of large size, in the leaves and other parts of Indian corn and teo- 

 siute, that are finally transformed into dusty masses of brown spores. 



No fungus is more widely distributed or better known than 

 corn-smut. Like other smuts, its germinating spores attack 

 young plants, its mycelium or spawn making its way upward 

 through their growing tissues without producing any evident ef- 

 fect until it prepares to fruit, when it increases and leads to the 

 formation of the smut-galls, that are ultimately filled with 

 myriads of round brown spores, each densely covered by short, 

 sharp s])inos. These spores, which measure ll-lo micro-millinie- 

 ters, preserve their power of germination for several years, or, in 

 fresh barnyard manure, etc., they develoj) at once, multiplying 

 indefinitely by the production of yeast-like secondary spores, 

 each of which has the i)ower of infecting a seedling corn plant. 



Gathering and burning the smut-galls and smutty ears, while 

 they are still green, to prevent the accumulation of spores in the 

 soil , rotating tho crop when smut has become firmly established 

 in a field; treating seed corn with copperas-water and lime, etc., 

 before planting; and using only old, well-rotted manure or arti- 

 ficial fertilizers, have all been proposed as preventives of smut. 



3. The leaf-smut of Timothy {TiUetia sfn'acformh-JVe.std.) 

 Forming black, smutty lines in the leaves of Timothy and other 



