CONTENTS. 7 



Department Bulletin No. 1067. — Tests of Drainage Pumping Plants in 



the Southern States: p age . 



Introduction 1 



Types of pumps 2 



Suction and discharge pipes 3 



Sources of power for pumping plants 5 



Tests of pumping plants 6 



Cost of operation of plants 44 



Department Bulletin No. 1068. — Farm Ownership and Tenancy in the 

 Black Prairie of Texas: 



Purpose and scope of investigation 1 



The development of tenure problems in the black land 4 



Economic aspects of the forms of tenure 15 



Agricultural history of farm operators 31 



Domestic, social, and educational conditions in relation to tenure 50 



Department Bulletin No. 1069. — Relation of Production to Income 

 from Dairy Cows: 



Purpose of the work 1 



Character of data used 2 



How the records were studied 3 



General averages of production, feed, cost, and income 4 



Quality of cow-testing-association cows 5 



Relation of butter fat production to income 5 



Prices and profits 14 



Relation of milk production to income 14 



What a cow-testing association can and can not do 19 



Summary and conclusions 20 



Department Bulletin No. 1070. — Farm Management in Catawba County, 

 North Carolina: 



Summary of results 1 



General description of area 3 



Type of farming and analysis of farm business 5 



Crop rotations 17 



Department Bulletin No. 1071. — Influence of Season of Freshening 

 on Production and Income from Dairy Cows: 



Basis of the data 1 



Influence of the season of freshening 2 



Value of products 3 



Milk and butter fat production 3 



Feed cost 5 



Income above feed cost 7 



Influence of month of freshening 7 



How the months ranked 9 



Conclusions 9 



Summary 10 



Department Bulletin No. 1072. — The Handling, Shipping, and Cold 

 Storage of Bartlett Pears in the Pacific States: 



Introduction 1 



I >i-t ribution of Bartlett pear growing in the Pacific Coast States 3 



Handling fruit for shipment in a fresh state 3 



ll; odling fruit for canneries 12 



The cold storage of Bartlett pe:irs 13 



St.or;i^(; temperature 13 



Pear scald 15 



Summary 16 



DM- Bulletin No. iot:'.. Some Changes r. the Composition of 



cado During Gro th: 



The California avocado industry ' 



Purpose of invest igation - 



! ional work — 



Method of ampling 8 



Met] ' 



.It of investigation ■' 



