MILLING AND BAKING TESTS OF WHEAT. 9 
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 Tiirsuta) . The 
latter species has short pods covered with fine, short hairs (hence the 
^^t^M^^^&f^ 
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 Mrsuta) , 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 
