of bobwhite food in six of the studies reviewed, includ- 

 ing those from three states (Missouri, Indiana, and Vir- 

 ginia) where the diets tended to be similar to that in 

 this study. Milk pea, pine, partridge pea, and sweet 

 gum were found in sizable amounts in most of the south- 

 ern states; Johnson grass was reported in appreciable 

 quantities in one southern and two Oklahoma studies. 

 West of the Mississippi River, sorghum formed a large 

 portion of the bobwhite diet. 



RELATIONSHIP OF AGRICULTURAL PRACTICES TO 

 FOODS AVAILABLE 



An effort was made to determine the relationship of 

 agricultural practices to the kinds and quantities of 

 foods taken by bobwhites. Those plant foods compris- 

 ing more than 0.25 per cent of the total volume of crop 

 contents were arbitrarily classified into three groups, 

 table 3: (1) cultivated, (2) associated with cultivation, 

 and (3) old-field native. Cultivated foods ixeTe those 

 produced by intentionally grown domesticated plants; 

 foods associated with cultivation were produced by 

 plants not intentionally grown on lands currently or 

 recently in cultivation; old-field native foods •were those 

 produced by plants found in advanced stages of succes- 

 sion on lands idle for a number of years. Korean and 

 Japanese lespedezas were classed as associated with 

 cultivation because the yearly acreage planted to these 

 lespedezas was small in southern Illinois; their abun- 

 dance and availability resulted from their persistence 

 and ability to spread. 



Cultivated plants formed 57.03 per cent of the vol- 

 ume of crop contents in 1950 and 1951 combined. In re- 

 ports from Missouri (Korschgen 1952:11), Virginia (Bald- 

 win & Handley 1946:149), and Oklahoma (Baumgartner 

 et al. 1952:356), cultivated foods constituted a smaller 

 amount of the food volume, 33.4, 25, and 29.0 per cent 

 respectively. In the present study, plants associated 

 with cultivation made up 16.68 per cent of the volume 

 of crop contents and old-field native plants 17.45 

 per cent. 



Cultivated foods found in bobwhite crops formed 

 64.43 per cent of the crop contents in 1950 and 46.98 

 per cent in 1951- Old-field native plants provided 9.80 

 per cent of the diet in 1950 and 27.79 per cent in 1951. 

 Foods associated with cultivation showed the least 

 change from one year to the next, comprising 18.07 per 

 cent of the volume in 1950 and 14.82 per cent in 1951- 



Although foods associated with cultivation were the 

 least important group by volume, they occurred with the 

 greatest frequency. Four items in this group (Korean 

 and Japanese lespedezas, common ragweed, bidens, 

 and smooth crabgrass) were found in more than 10 per 

 cent of the crops examined; only two cultivated foods 



(corn and soybean) and two old-field native foods (des- 

 modium and small wild bean) occurred with similar 

 frequency. 



The availability of cultivated foods in fall and early 

 winter is affected by the time of harvest of agricultural 

 crops. The supply of grain as food for the bobwhite is 

 greatest immediately after the harvest; many cultivated 

 foods are relatively inaccessible to the bobwhite before 

 the harvest. 



The times of planting and harvesting operations in 

 1951 were near normal, and, although they were some- 

 what later than usual in 1950, they were not much de- 

 layed. For both years, 95 per cent of the soybean crop 

 was combined by the end of October, while the com 

 harvest was largely completed by late November. 



Soybean, cowpea, and wheat are believed to deterio- 

 rate rapidly after exposure on the ground, while corn is 

 relatively durable. If the grains that deteriorate rapidly 

 are harvested later than usual, they maybe more readily 

 available to the bobwhites during the hunting season 

 than if they are harvested at the usual time. This as- 

 sumption offers a suitable explanation of the greater 

 importance of soybean and cowpea in 1950 but fails to 

 explain why wheat, presumably even more vulnerable 

 to deterioration than these legumes, formed a larger 

 portion of the diet in 1951, a year of earlier harvest and 

 of adverse weather. 



Perhaps an explanation lies in the food-cover rela- 

 tionship, figs. 6, 7, and 8. Harvested fields of soybean 

 and cowpea are so nearly denuded of cover that bob- 

 whites tend to restrict their feeding to the field borders. 

 On the other hand, harvested wheat fields are more 

 likely to be utilized by bobwhites than the interiors of 

 dense, tall, uncut wheat stands. Possibly wheat, as 

 well as the old-field native foods, made up a larger 

 percentage of the diet in 1951 because the slightly 

 earlier harvests of all crops that year, as compared to 

 1950, forced many of the birds out of the fields of har- 

 vested legumes. The deep snow of November 6-7, 1951, 

 may well have abetted, or even initiated, this movement. 



INFLUENCE OF WEATHER ON DIETARY PATTERN 



Yearly, seasonal, and even daily variations in the 

 food consumed by bobwhites may result from weather. 

 Any one of a number of closely related factors may re- 

 sult in a varying diet. During the growing season, weather 

 influences the quantities of plant and animal species 

 that are produced; the amounts of each are affected 

 throughout the year. Weather also determines the time 

 that plants become ripe and has some effect on the 

 quality of their seeds. Agricultural practices, which 

 can in themselves influence what foods are available 

 to the bobwhite, are somewhat dependent on daily as 



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