THE OAT CROP. 117 



had in generations long past established the same facts ; and man, by his steady cultiva- 

 tion of the crop, has shown the estimation in which it has ever been held by him. It 

 becomes still more important, from the fact that it may be cultivated in higher latitudes 

 than some of the other cereals, and rarely in a northern climate disappoints the farmer. 

 The amount of organic elements in a bushel of oats weighing 32 lbs. is as follows : 



lbs. oz. 



Starch ....... 17 4 



Casein or avenine ..... 49 



Albumen ....... 04 



Gluten 8 



Dextrine 2 15 



Sugar and extract - - - - - Oil 



Oil 2 6 



Water 3 4 



32 



Diseases of the oat. 



The oat, in certain fields, especially those that are weedy, is subject to disease ; or 

 rather to the attack of a fungous plant, whereby almost every kernel upon the panicle or 

 head is totally destroyed. This fungus is called by authors Uredo avencc. It is a species 

 of smut. The kernels, or the places where they would have grown, is filled with a black 

 smutty substance, which finally becomes dry enough to send out a powder of extreme fine- 

 ness, which is really a cloud of seeds capable of germinating and growing, and producing, 

 like other seeds, individuals similar to the parent. 



The smutty heads are well known undoubtedly to farmers, inasmuch as many may be 

 found in most fields of oats. In addition to the smutty panicle, the whole plant is stinted, 

 being shorter and more erect than the healthy one. The coverings of the grain, the 

 husks, are apparently corroded through, so as to show upon the side the black mass within 

 them. The spores, or seeds which have been already alluded to, are extremely minute 

 rounded particles, whose forms are only made known by the aid of a powerful microscope. 

 They are globular grains, not uniform in size, but with a diameter which does not exceed 

 33V a °f an inch- These minute atoms are scattered over the field, and lodged in the soil ; 

 and, without doubt, if we may rely upon analogy, they retain for a long time the power of 

 germinating, and will do so when a favorable opportunity occurs. This fact renders it 

 highly desirable that every smutty plant should be eradicated and burnt, when it first 

 shows any symptoms of the disease in question ; for undoubtedly the spores are taken up 

 by the roots, and conveyed to heads of the grain, where they at once begin the work of 

 destruction. 



The fungous plant, which appears so much like a gangrene of the grain, is represented 

 on Plate LV, fig. 23, in the first stage of its growth. It, however, more frequently appears 



