dix. On the basis of volume or frequency of occurrence 

 only a few of these were of importance in the diet; the 

 first 10 foods by volume are presented in fig. 3 and by 

 frequency of occurrence in fig. 4. Only 12 plant and 2 

 animal foods individually comprised 1 per cent or more 

 of the total volume, fig. 5; together, they formed 92.53 

 per cent of the crop contents in both years combined. 

 A few foods accounted for most of the volume. Com and 

 soybean, ranking first and second, together made up 

 50.22 per cent of the total volume. These and the next 

 highest ranking foods — Korean and Japanese lespedezas, 

 acorns, and wheat — made up 7 1.5 2 per centof the volume. 



Variations in relative volume from one year to the 

 next were noted. In 1950, 14 foods and, in 1951, 12 

 foods individually accounted for 1 per cent or more of 

 the volume. Com, soybean, Korean and Japanese les- 

 pedezas, acorns, wheat, common ragweed, slugs, jewel- 

 weed, bidens, and short-horned grasshoppers were among 

 these foods in both years. Cowpea, small wild bean, 

 yellow foxtail, and smooth crabgrass formed more than 

 1 per cent of the volume in 1950 but smaller percent- 

 ages in 1951. White sassafras and desmodium constitut- 

 ed 1 per cent or more of the volume in 1951 only. Com 

 and soybean ranked first and second by volume both in 

 1950 and in 1951. 



Korean and Japanese lespedezas, corn, and common 

 ragweed ranked in that order in frequency of occurrence 

 both in 1950 and in 1951. Soybean, bidens, and small 

 wild bean were each found in more than 10 per cent of 

 the crops in both years. Smooth crabgrass, yellow fox- 

 tail, and witch grass each occurred in more than 10 per 

 cent of the crops in 1950 only; desmodium, acoms, and 

 white sassafras in 1951 only. 



Soybean comprised 29.05 per cent of the total volume 

 in 1950 but only 13.47 per cent in 1951. The frequency 

 of occurrence of soybean fell from 26.20 per cent in 

 1950 to 17.04 per cent the following year. Other impor- 

 tant foods which showed marked variations in relative 

 volume in the two years were white sassafras, wheat, 

 cowpea, acorns, desmodium, and bidens. Com, Korean 

 and Japanese lespedezas, common ragweed, slugs, jewel- 

 weed, short-horned grasshoppers, and small wild bean 

 showed little quantitative change from 1950 to 1951. 



Some of the foods taken in small quantities also 

 exhibited comparatively marked variations in amounts 

 taken in 1950 and in 1951. Black gum was particu- 

 larly notable in that it constituted 0.77 per cent by vol- 

 ume of the crop contents and appeared in 0.59 per cent 

 of the crops in 1950 but did not appear in 1951. 



Food items forming 1 per cent or more of the total 

 volume for 1950 and 1951 combined, table D, Appendix, 

 are herewith discussed in some detail. They are pre- 

 sented in descending order of rank by per cent of vol- 

 ume of total crop contents. 



1. Corn, found in greater quantity than any other 

 food, constituted 27.79 per cent of the total crop con- 

 tents. It was present in 28.85 per cent of the southern 

 Illinois bobwhite crops examined, ranking second in 

 frequency of occurrence. The amount of this food re- 

 flects, among other things, its agricultural importance 

 and general availability in southern Illinois. In the diet 

 of certain Indiana bobwhites, corn was first by volume 

 (27.4 percent) and occurred in 29.1 per centof the crops 

 (Reeves 1954:43). It was the most important winter food 

 of bobwhites studied in eastern Nebraska (Damon 1949: 

 25). In a Missouri study (Korschgen 1948:52), it ranked 

 second by volume (16.8 per cent) and occurred in 22.2 

 per cent of the crops. 



2. Soybean made up 22.43 per cent of the total crop 

 contents and ranked fourth in frequency of occurrence; 

 it was found in 22.08 per cent of the Illinois crops ex- 

 amined. As in the case of corn, the importance of soy- 

 bean in the food of southern Illinois bobwhites probably 

 reflects its agricultural importance and general avail- 

 ability in the study area. This legume was not found in 

 large proportions in other studies of bobwhite foods. In 

 Indiana, Reeves (1954:43) found that soybean made up 

 4.0 per cent of the volume, ranking fifth. For Missouri, 

 Korschgen (1948:52) reported that soybean ranked sev- 

 enth (2.6per cent) by volume. Baldwin & Handley (1946: 

 145) ranked it third by volume (7.6 per cent) in Virginia. 

 Cady (1944:12) found that soybean and cowpea together 

 held fourth place by percentage of total weight (3.57 

 per cent) in the Tennessee area he studied. 



3. Korean and Japanese lespedezas were third by 

 volume (8.66 per cent of crop contents) but first in fre- 

 quency of occurrence (42.23 per cent) in southem Illi- 

 nois. In the cases in which each could be specifically 

 designated, Korean lespedeza comprised approximately 

 90 per cent of the total volume of the two species and 

 occurred approximately three times as often as Japanese 

 lespedeza. Compared to the com and soybean acreage, 

 the yearly acreage planted in Korean and Japanese 

 lespedezas within the study area was small. However, 

 the persistence of these lespedezas and their ability to 

 spread undoubtedly made them widely available. Many 

 other studies have shown these lespedezas to be impor- 

 tant as food for bobwhites. In a Missouri study in which 

 the species were listed separately, Korean lespedeza 

 ranked first by volume (17.4 per cent) and first in fre- 

 quency of "occurrence (44.8 per cent), while Japanese 

 lespedeza made up 1.1 per cent of the volume and oc- 

 curred in 14.0 percent ofthe crops (Korschgen 1948:52). 

 In an Indiana investigation (Reeves 1954:43), Korean 

 lespedeza was third by volume (15.7 per cent) and first 

 in frequency of occurrence (55.8 per cent). In a report 

 from Virginia (Baldwin & Handley 1946:145), Japanese 

 lespedeza ranked second by volume (9.7 per cent). A 



