216 now CROPS feed. 



bled rye to yield a maximum of grain and brought wheat 

 ana oats very closely to a maximum crop. Hcllriegel no* 

 ticed tliat the plants exhibited no visible symptoms of 

 deficiency of water, except through stunted growth, in 

 any of these experiments. Wilting never took place ex- 

 3ept wlien the supply of water was less than 2' \,^ per cent. 



Grouven {Ueber den Zuscwimenhcmc/ zwischen Wit- 

 teriou/, JBoden und Daitgung in ihrem Einjlusse auf die 

 Quant itiit und Qualitut der Erndten., Glogali, 186s) gives 

 the results of an extensive series of field trials, in which, 

 among other circumstances, the influence of water upon 

 the crops was observed. His discussion of the subject is 

 too detailed to reproduce in this treatise, but the great 

 influence of the supply of water (by rain, etc.,) is most 

 strikingly brought out. The experimental fields were 

 situated in various parts of Germany and Austria, and 

 were cultivated with sugar beets in 186:2, under the same 

 fertilizing applications, as regards both kind and quantity 

 Of 14 trials in which records of the rain-fall were kept, 

 the 8 best crops received from the time of sowing. May 

 1st, to that of harvesting, Oct. 15th, an average quantity 

 of rain equal to 140 Paris lines in depth. The 6 poorest 

 crops received in the f^ame time on the average but 115 

 lines. During the most critical period of growth, viz., 

 between the 20th of June and the 10th of September, the 

 8 best crops enjoyed an average rain-fall of 90.7 lines, 

 while the 6 poorest received but 57.7 lines. 



It is a well recognized fact that next to temperature, 

 the water supply is the most influential factor in the prod- 

 uct of a crop. Poor soils give good crops in seasons ot| 

 plentiful and well-distributed rain or when skillfully irri-^ 

 gated, but insufficient moisture in the soil is an evil that' 

 no supplies of plant-food can neutralize. 



The Functions of Water in the Nourishment of 

 Vegetation) so far as we know them, are of two kmd& 



