THE INFLUENCE OF WATER ON VEGETATION. 



make a large development of leaves and branches without producing any fruit. Taking 

 that familiar flowering plant, the Camellia, as an illustration — during its growth it de- 

 lights in a free supply of moisture, both in soil and atmosphere; if these conditions are 

 kept up uninterruptedly after the seasonal growth is completed, it will not form flower buds, 

 but immediately start into a second growth. On the other hand, as soon as the young 

 shoots are done growing, let the plant be placed in a dryer atmosphere, and the supply of 

 water to its roots diminished, and almost every bud will be converted into a flower bud. 



The ripening of fruit is also accelerated by lessening the supply of water to the roots 

 during this process. This may readily be supposed, seeing that it has the same organic 

 connection with the roots as the flowers and leaves. When in a young, green state, the 

 fruit performs the same functions as the leaves, absorbing carbonic acid and giving off oxy- 

 gen, thus elaborating matter for itself so long as it remains of a green color. Its principal 

 dependence for nourishment, however, is from the leaves. Fruit formed upon naked 

 branches will rarely ripen to perfection without the assistance of leaves. Its intimate re- 

 lation and dependence upon the leaves renders it similarly affected by change of circum- 

 stances. " One of the most essential of the alterations which occur in fruits during ri- 

 pening, is the decomposition or dissipation of the water that they attract from the stem. 

 A diminished supply of water will, under equal circumstances, produce an accelerated 

 maturation, because less time will be required to decompose or dissipate this element; and, 

 on the other hand, an excessive supply of water will retard or prevent ripening, in conse- 

 quence of the longer time required for the same purpose." (Lindley.) 



The amount of cold that plants are capable of enduring, depends in a great measure 

 upon the quantity of water contained in their structure. We frequently see plants at one 

 time killed with an amount of frost that in previous occasions did not injure them. The 

 soft, watery, immature points of shoots, are also frequently killed, while the rest of the 

 plant remains uninjured. Mild, moist winters, followed by severe spring frosts, are more 

 injurious to vegetation than those of earlier severity, because in the former case the roots 

 are constantly sucking fluid from the soil and driving it upwards into the system, the 

 whole plant becomes distended with watery particles, and owing to the expansion of water 

 in freezing, the bark is frequently rent asunder, and the plant otherwise injured. Hence 

 the proprirty of inducing early maturity — checking the growth by withdrawing moisture, 

 that the shoots may become less hard and solidified, and enabled to withstand cold; and 

 hence, also, the fact that plants flower and fruit more profusely and withstand the rigors 

 of climate with less injury, on well drained lands, than in those constantly saturated with 

 moisture. A wet soil is truly a cold one. Where there is water, the rays of heat pene- 

 trate very slowly; the more water the greater the evaporation, and evaporation alwaj's 

 produces cold. 



Attention to these facts is of much importance to those having the management of green- 

 house plants during the winter. By a proper preparatory treatment these can be inured 

 to bear a degree or two of frost without injury; and in severe weather it is preferable to 

 allow this falling off" of the atmosphere, rather than have recourse to high artificial heat, 

 which is often given to an amount not only useless, but decidedly injurious. I have fre- 

 quently allowed the thermometer to fall as low as 29° in a house containing not only an 

 average collection of what are usually considered green-house plants, but also many that or- 

 dinarily receive hot-house treatment, as Ixoras, Stephanotis, Eschynanthus , Gardenias, 

 &c. In a common wooden frame sunk in the earth, with no other protection than tliat 

 ded by the glazed sash, and a close canvass cover elevated a few inches from the glass 

 kept Verbenas, Roses, Carnations, &c., together with young plants of lettuces and 



