2 FRUIT BOOK. 



spreading wide, may be necessary to produce 

 large timber trees, but not fruit trees ; for these 

 are more prolific when their roots are much divid- 

 ed or fibrous, and kept near the surface of the 

 soil." 



The following remarks upon the theory of the 

 motion of the sap in trees is from the pen of 

 one of our best writers upon horticulture : 

 " The first motion of the sap in the spring takes 

 place in the branches, and lastly in the roots ; the 

 buds, in consequence of the increasing tempera- 

 ture of the air, first swell and attract the sap in 

 their vicinity : this fluid, having lain dormant, or 

 nearly so throughout the preceding winter, be- 

 comes gradually expanded by the influence of the 

 solar rays, and supplies the buds with nourish- 

 ment from the parts immediately below them ; the 

 vessels which yield this supply, becoming in conse- 

 quence exhausted, are quickly filled with fluid from 

 the parts below them ; and in this manner the mo- 

 tion continues until it reaches the roots, the grand 

 reservoir of the sap, by which time, the solar heat 

 having penetrated the soil, the roots begin to feel 

 its enlivened influence. The whole body of sap 

 then begins to move upwards ; and as soon as the 

 quantity propelled is more than sufficient to dis- 

 tend all the vessels in the stem and the branches, 

 the buds begin to elongate and unfold. From 

 this time, the fluid becoming more expanded every 

 hour, its ascent is simultaneously increased in 

 force and velocity ; the vessels in the branches 

 being filled to repletion, the buds x quickly open, 

 and shoots and leaves rapidly protrude ; the leaves 

 attract the sap as soon as it reaches their vicinity, 

 and, by one of the most wonderful processes that 



