AGRIGULTURE FOR SOUTHERN SCHOOLS. 29 
Lesson 4.—Construction of Tile Drains. 
1. Ditching methods. 
2. Laying the tile. 
Exercise 2.—Laying Tile. 
See Farmers’ Bulletin 638, Exercise 36, Digging Ditch and Laying 
Tile. 
IRRIGATION. 
(2 lessons, 1 exercise. ) 
References.—Irrigation in Humid Climate, Farmers’ Bulletin 46. Possibilities 
and Needeof Supplemental Irrigation in the Humid Regions, Yearbook Separate 570. 
Lxsson 1.—Relation of Irrigation to Agriculture. 
1. History of irrigation. 
2. Present status ofirrigation farming. 
3. Supplemental irrigation in humid regions. 
Lesson 2.—Practical Irrigation. 
1. Laying out the ditches. 
2. Use of water in irrigation. 
Special references.—The following Farmers’ Bulletins: 138, Irrigation in Field and 
Garden; 158, How to Build Small Irrigation Ditches; 263, Practical Information for 
Beginners in Irrigation. 
ExeErcisE.—Preparing Garden for Irrigation. 
See Farmers’ Bulletin 638, Exercises 38, 39, and 40, Irrigation. 
TERRACING. 
(2 lessons, 1 exercise.) 
Reference.—The Mangum Terrace in Its Relation to Efficient Farm Management, 
Bureau of Plant Industry Circular 94. 
Lesson 1.—Purposes of Terracing. 
1. Gullying and other forms of erosion. 
2. Contours and terraces in ornamental planting and orchards. 
3. Types of terraces. 
Lesson 2.—Construction of Terraces. 
1. Laying out contour lines. 
2. Use of the A frame and other forms of levels. 
3. Making the terrace. 
ExeErcise.— Construction and Use of Terrace Level. 
See Farmers’ Bulletin 638, Exercise 37, Laying Out and Building a 
Terrace. 
ROADS. 
(3 lessons, 2 exercises.) 
References.—The following Farmers’ Bulletins: 311, Sand-clay and Burnt-clay 
Roads; 321, The Use of the Split-log Drag on Earth Roads; 338, Macadam Roads; 
505, Benefits of Improved Roads; 597, The Road Drag and How It Is Used. 
Lesson 1.—Importance of Good Roads. 
1. Relation of farming to roads. 
2. Financial benefit. 
3. Social benefits. 
