6 DEPARTMENT OE AGRICULTURE BULS. 201-225. 



Department Bulletin 219.— Corn in the Great Plains Area: Relation of 



Cultural Methods to Production. Page. 



Introduction 1 



Area covered by these studies 3 



( limatic conditions 4 



General plan of the investigations 6 



Comparison of cultural methods 10 



Results of individual stations 13 



General discussion of results 26 



Conclusions 31 



Department Bulletin 220. — Road Models. 



Introduction 1 



Roman roads 2 



French roads 3 



Macadam method of construction 5 



Telford method of road building 6 



Location and alignment 7 



Foundation, or subgrade, and shoulders 7 



Earth and sand-clay roads 10 



Gravel roads 12 



' Macadam roads 13 



Cement concrete roads 17 



Bituminous concrete roads— " Topeka specification' ' 18 



Paved roads other than concrete 18 



Culverts and bridges 20 



Roadside treatment 21 



Road machinery 22 



Department Bulletin 221. — The Southern Corn Leaf-beetle. 



Introduction 1 



History ■ 2 



Distribution 3 



Discription and life-history notes 3 



Crops damaged 8 



Dissemination 9 



Remedies 9 



Literature cited 10 



Department Bulletin 222. — Barley in the Great Plains Area. 



Introduction 1 



Importance of barley as a grain crop 3 



Area included in these investigations 3 



Climatic conditions , 4 



General plan of the investigations 5 



Comparison of cultural methods on the basis of cost 9 



Results at the several stations 12 



General discussion of results 28 



Conclusions 31 



Department Bulletin 223.— Botanical Characters of the Leaves of the 

 Date Palm Used in Distinguishing Cultivated Varieties. 



Introduction 1 



The date tree ' 3 



Leaf characters of the date , 3 



Use of the field protractor 13 



Forms for the observer's use 13 



Application of the system to the Deglet Noor variety and its seedlings 16 



Department Bulletin 224. — A Study of the Preparation of Frozen and 

 Dried Eggs in the Producing Section. 



Introduction 1 



Review of the egg-breaking houses as seen in 1911 2 



Plan for the experimental work of 1912 3 



General statement of the investigation and the results 4 



Classes of eggs presenting special problems 9 



Comparative study in two houses on eggs before and after dessiccation 15 



Comparison of the liquid product from three houses in 1912 16 



General summary of laboratory results on commercial samples, 1912 18 



Conclusions 20 



