4 PLANT LIFE ON THE FARM. 



cumstances, which we need only mention, as their effects 

 will he readily understood without the necessity of expla- 

 nation. 



It is clear then that a suitable temperature and access of 

 water, either liquid or in the form of vapour, are the first 

 essentials in the feeding process in plants. Practically, 

 and from force of circumstances, the gardener has more 

 control over "both temperature and the supply of water than 

 the farmer ; nevertheless hy drainage, by choice of aspect, 

 site, by shelter, and other means, even the farmer has some 

 power to regulate the temperature and the amount or in- 

 fluence of water to which his crops are subjected. 



"Water. Leaving, however, on one side, the temperature, 

 we have to consider the water which is so essential, not only 

 in the feeding processes with which we are now concerned, 

 but with every other action of plant life. Fortunately there 

 is, in general, no lack of it ; the earth and the air contain their 

 shares of this elementary compound in varying proportions 

 and varying modifications as liquid or gaseous. Besides, 

 the plant itself has so much of it that even at the driest 

 condition compatible with life it still constitutes a very large 

 proportion of the entire weight. Now, it is as a rule when the 

 plant, the seedling, or the bud is at its driest that growth 

 begins, the necessity for food first manifests itself, and the 

 demand for a further supply of water becomes imperative. 

 How is the demand supplied ? We have seen that there is 

 no lack of that fluid. How is it to get into the plant? 

 The answer to this question brings us at once to the con- 

 sideration of the raw material and of the fabric of plants by 

 whose agency alone it is that the water gains entrance to 

 the plant. 



