wiii CONTENTS 



V. Hotbeds and Coldframbs : / 49 



Uses — Plants for the Coldframes — -Plants for Hotbedfi 

 — ^How to Make a Hotbed — Exercise — Making a. 

 Hotbed — How Hotbeds are Warmed — ColdfraHies 

 and Hotbeds Compared — Operating a Hotbed — The 

 Temperature — The Ventilation — The Moisture. 



VI. PuiNTS IN Relation to Soil, Light and Air. 58 



Absorbing Moisture— Root Hairs on Young Plants — 

 Root Hairs Form Early — Leaves Expel Moisture — 

 Osmosis — Overfeeding of Plants — Sunlight Needed 

 for Growth — Leaves and Light — -Plants Use Carbon 

 Dioxide — Balance Between Plants and Animals — - 

 Types of Roots. 



VIL Home and School Exercises 66 



Studies of Seeds and Germination — ^Garden Seeds 

 Selected — How Plants Get Out of the Ground — ^Plant 

 Growthand PoUination — Experiments in PlantGrowth 

 — Moisture and Germination — Packing and Germina- 

 tion — ^Air and Germination — Warmth and Germina- 

 tion — Depth and Germination — Carbon Dioxide from 

 Germinating Seed — Importance of Large Seed — Seed 

 Testing, Soil Method— Seed Testing, in Wet Cloth — 

 Looking for Weed Seeds — Studying Weed Seeds — 

 Weed Distribution — Getting Pure Grass Seeds — Oil 

 in Seeds — Starch in Seeds — Gluten in Seeds — Better 

 Seed Potatoes — Studies of Flowers and Pollination — 

 The Parts of a Flower — -Wind and Insect Pollinating — 

 Pollination of Corn — -Hand PoUination. 



VIII. The Soil and Its Improvement 84 



Preparing the Soil — Liming — Green Manure — Cover 

 Crops — Humus — Barnyard Manure — Compost — Care 

 of Manures — Exercise in Commercial Fertihzers — 

 Nitrogen — -Effect of Nitrogen — ^How much Nitrogen 

 to Apply — Phosphoric Acid — -Phosphorus — ^Making 

 Phosphoric Acid — Testing for Phosphoric Acid — 

 Potash — Wood Ashes as Plant Food — How to Buy 

 Fertilizers — Home Mixing — -Home Mixing of Fertil- 

 izers — Which Fertilizer to Use — Improvement by 

 Tillage — Depth of Plowing — Shallow Tillage — Bare 

 Fallow — Killing Weeds — -Legume Nodules — Inocu- 

 lating Soil for Legumes — Lime for Legumes — Amount 

 of Mineral Matter in Plants — Soils Retain Plant- 

 food — Rains Remedy Over-fertilizing — Minerals in 

 Soil Water — Solubility of Lime — Fertilizer Samples. 



IX. Irrigation and Drainage 106 



Irrigation — Irrigation in Humid Regions — The Water 

 Supply — ^Water is Raised — Conveying the Water — 

 After Treatment — Liquid Manure — Drainage — Kinds 

 of Drainage — Covered Drains — Installing Drains — - 

 Cost of Drainage. 



