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FIG CULTURE 



4. The liability to freeze of the fluids contained 

 in plants is greater in proportion to the size of 

 their cells. 



5. The power of plants to resist extremes of 

 temperature is in a direct proportion to the quantity 

 of confined air which the structure of their organs 

 gives them the means of retaining in their more 

 delicate parts. 



6. The power of plants to resist extremes of tem- 

 perature is in direct proportion to the capability 

 which the roots possess of absorbing sap less ex- 

 posed to the external influence of the atmosphere 

 and the sun. 



Under the subject of wind-breaks an illustration 

 is given of a freeze which occurred in 1909, affect- 

 ing dissimilarly several orchards in the same local- 

 ity, being accounted for by the different composi- 

 tion of soils. When we consider how well air cir- 

 culates through the entire fibrous tissue and how 

 quickly the temperature of even heartwood is thus 

 changed, the roots imbedded in clay responding 

 more slowly to atmospheric influences than exposed 

 parts, light porous soil and warm weather easily 

 account for top growth at any time the winter be- 

 comes mild. When even the oak is so injured by a 

 late freeze that new bark is "hide-bound," interfer- 

 ing with growth to the extent of rendering the tree 

 unable to mature a crop of acorns, it is little wonder 

 that frost does so great damage to the soft, coarse 

 fibred fig wood. 



