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Cruciferous Root Vegetables 
Poole, C. F. 
1937. Improving the root vegetables. U. S. Dept. Agr. Yearbook 1937: 
300-325. 
p. 310: The cruciferous root vegetables— turnips, ru tabag as, 
and radishes — have relatively large flowers, which are insect-po llinated. 
Onion 
Jones, H. A. 
1937. Onion improvement. U. S. Dept. Agr. Yearbook 1937: 233-250. 
p, 239: Most of the pollen is shed between 9 a.m. and 5 p.m. 
Pollination is effe c ted mainly by insects that go from flower to 
f lower and visit the nectaries a t the base of the three in n er stam ens . 
Interpollination among flowers of the same umbel is no doubt of fre- 
quent occurrence, as the same insect has been observed to visit many 
flowers on an umbel before leaving. In the onion, however, cross- 
pollination is the rule. 
Pepper . , 
Odland, M. L., and Porter, A. N. 
1941. A study of natural crossing in peppers ( Capsicum frutescens) . 
Amer. Soc. Hort. Sci. Proc. 38: 585-588, tables. 
p. 588: The pepper flower is rather inconspicuous and non- 
fragrant, a fact that would suggest pollination not very likely. 
Erwin ... found that the flowers produced nectar and that insects 
did at times visit them. Th e writers are of the opinion that h oney 
bees are large l y responsible for the cross pollination that takes 
place . This insect has been found working on the pepper plant rathe r 
often. The_pre sen. ce._of the bee is rather spasmodic, however, as the y 
ar e found only on cer tain w arm b right days. T he pr esence of bees in 
the vicinity may have a bearing on the amount ofcrcss po l lination . 
Soybean 
Morse, W. J., and Cartter, J. L. 
1937. Improvement in soybeans. U. S. Dept. Agr. Yearbook 1937: 1154- 
11E9. 
p. 1167: Natural crossing in soybeans is undoubtedly brought 
aDOut by small insects. Thrips have been observed to be very common 
in the soybean flowers at the Arlington Experiment Farm. Beesand 
other, _insects have also been observed working on soyo g an flowers . 
Studies by many investigators at various places indicate that soybean 
plants growing in contact with one another are more likely to be 
crossed tnan plants separated by a few feet. 
