MII.IJNC AND IIAKIMI TESTS OF WHEAT. 



WILD VETCH 





Wild vetch (Vicia angustifolia) is a narrow-leaved species, closely 

 related to common vetch, and is an annual weed growing about 1 to 2 

 feet high in fields and waste places. The seed is nearly round, black 

 or dark brown in color, and, as a rule, fully as large as corn-cockle seed. 

 For this reason it is difficult to separate it from wheat, and when 

 present in appreciable quantities it lowers the grade and reduces the 

 price given for the wheat. Although this weed is neither so prevalent 

 nor so abundant as corn cockle, yet in some localities, especially in 

 sections producing spring wheat, it is found in such amounts as to be 

 a pest. The species of wild-vetch seed found in the wheat samples 

 secured at country points consisted largely of the narrow-leaved 

 vetch and to a lesser extent the hairy-pod vetch ( Vicia Mrsutd) . The 

 latter species has short pods covered with fine, short hairs (hence the 



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fa ^^^H^^y^^^Z^ 



Fig. 4. 



-Wheat containing 3.8 per cent of wild-vetch seed and 1.5 per cent of other foreign matter, as 

 unloaded from a farmer's wagon at a country elevator. (Natural size.) 



name liirsuta), while the narrow-leaved vetch has black pods an inch 

 or more in length. 



Because it was not feasible to secure a sufficient amount of wild- 

 vetch seed for use in the milling and baking tests which were made to 

 study the effects of such an impurity in wheat, hairy-vetch seed 

 (Vicia villosa), which is very similar in size and shape, was substi- 

 tuted for wild vetch. Hairy-vetch seed is less highly colored than 

 seed of the wild vetch, which has a reddish orange-colored meat, and 

 possibly the effect on the color of the crumb of the loaf was less pro- 

 nounced than would have been the case if wild-vetch seed had been 

 used. Where 1 per cent of hairy-vetch seed is present in wheat as 

 ground, the flour will have a yellowish appearance and a noticeable 

 odor of vetch. When milled alone, hairy-vetch seed gave a flour 

 yield of about 58 per cent. It was hard to bolt, having a somewhat 

 gummy consistency. The color of the flour was similar to that of 

 powdered sulphur and consequently when blended with wheat flour 

 it imparted a yellowish tint to the bread. 



Figure 4 shows a sample of spring wheat containing 3.8 per cent of 

 wild-vetch seed by weight, in addition to the other impurities, con- 

 10373°— Bull. 328—15 2 



