270 CORYLACEiE. 



side of the new road and nearly a quarter of a mile in 

 length, was deeply trenched,* and a small portion manured 

 in addition. 



The rest of the ground, adjoining the strip on each side, 

 was planted in the usual manner, either by pitting or 

 slitting, as seemed to suit the nature of the soil, a large 

 proportion being a strong loamy clay, the remainder of a 

 lighter nature with a mixture of gravel. The trees planted 

 consisted of Oak, beech, wych elm, sycamore, and larch, 

 with a sprinkling of silver, spruce, and Scotch firs. Six 

 years after planting, the trees in the trenched ground 

 seemed fully established, having, from the second season 

 after they were put in, made long and vigorous shoots, 

 and had reached a considerable size, while those in the 

 untrenched part seemed at that age to be only recovering 

 from the effects of transplantation, or just beginning to 

 push freely away ; at twelve years old, the plants in the 

 trenched ground still continued to grow rapidly and luxu- 

 riantly, and were far ahead of their neighbours, but the 

 latter had now begun to push vigorously, and to make 

 strong and lengthy shoots ; at fifteen or sixteen, the shoots 

 of the trees in the trenched parts began visibly to decrease 

 in length and vigour, in consequence, we may suppose, 

 of the rapid exhaustion of the trenched soil, and the 

 descent of the roots to the unmoved stratum below, which 

 gave, as it appeared, a sudden check to their previously 

 rampant growth ; no check of this kind took place with 

 the other trees, as they continued to advance steadily 

 and rapidly every season ; at the end of twenty years, 

 though the trees in the trenched parts continued healthy, 

 the annual growth of those in the untrenched ground 

 had, for the last four or five years, exceeded theirs, and 



* The cost of trenching at that period was 1 01. per acre. 



