Contents 



CHAPTER XXI 



CONIFERS 



PAGE 



Werchojansk — Polar coniferous forests — Frozen soil — Northern forests — 

 Scotch pine — British Columbian forests — Larch in Europe — Larch 

 disease — Sequoia of California — Monkey puzzle forests — Primaeval 

 forest in Bohemia — Highland woods — Woodfloor plants — Area of 

 forest in Britain — Royal Commission — Forestry prospects — Labour 

 — Finest Scotch conifers 236 



CHAPTER XXII 



ARABLE LAND 



England before 1789 — Nomadic agriculture — King Alfred— Irish system 

 — Braunton Great Field — Commons and Enclosures — Preparation 

 of the land — Origin of weeds — Rate of travel — Weeds reclaiming 

 clay — Vicia orobus in Germany — Times of flowering — Underground 

 runners — Thistles, electrocution and spraying — Numbers of weeds 

 — Production of Britain per acre — Food-supply in war . ,__ . 250 



CHAPTER XXIII 



GRASS 



Bamboos — Australian grasses — Rice and oats — Shooting of grass — 

 Tussocks— Steppe grasses — Flowering and colours — Mechanical 

 system — Hygroscopic awns and sheep-killing — Prairies and fires — 

 Effect of fires on trees — Wasteful system of agriculture —Grass 

 pasture — Food value, vigour, method of growth, quickness of 

 development, germination, preferences and price of the various 

 grasses in pasture — Mr. R. H. Elliot 261 



CHAPTER XXIV 



FORTUNATE ISLANDS 



Utopias — Cocoa-nut, banana and sago palm — Teneriffe and Von Hum- 

 boldt — Zones of vegetation — Colonisation of lava flows and tree 

 branches — Orchid seeds — Shorea fruits travelling — Bird migration 

 — American seeds on the Hebrides — Navigator seeds of the Pacific 

 — Currents and floating seeds — Development of new species in 

 islands — Araucaria distribution — Giant lobelias .... 274 



CHAPTER XXV 



PRACTICE OF PLANT-BREEDING 



Selection of best single seed — Sea island cotton crisis — Seven-leaved 

 clover — Natural hybrids— Fern mongrels — Mr. Biffen's wheats — 

 Orchid crosses — Luther Burbank — Prune-trees in a year and a half 

 — Bonfires — Walnut hybrids — Spineless cacti — Larch experiments 

 — Effect of altitude on seed — Sycamores and leaf fall — Varying 

 conditions — Potatoes in icehouse — Degeneration of potatoes — Fife 

 wheat 284 



xiii 



