CHAPTER XXI

TILLAGE 220-229

Desirable physical condition of the soil 220

The breaking-plow 221

Types of plows 221

Subsoiling 223

Time of plowing 223

Method of plowing 224

The disk harrow 225

Cultivation of plants 227

Controlling root-growth 227

Elimination of competition 228

Length of cultivation 229

Crops and Methods for Soil Improvement · 第 21 / 25 章