AND U. S. EXPERIMENT STATION. 



The culture for the year consisted of the frequent use of the har- 

 row tooth cultivator. The last cultivation was given July 31st. The 

 trees were hoed three times during the season. 



GROWTH OF ROOT. 



In the latter part of September, trees of each of the varieties of 

 seedlings above noted, were carefully taken up. 



In digging the green ash it was found that the root descended al- 

 most in a vertical line. It was traced down three feet and two inches, 

 where it was still the thickness of knitting cotton. In its descent it 

 passed through the black loam, into which the strongest lateral roots 

 grew, thence through a six inch stratum, poorly defined, of gravelly 

 loam, thence through a foot of yellow clay of somewhat loamy texture, 

 finally penetrating into the stiff clay which contains white chalky de- 

 posits, wrongly called by many people, "hard pan." The tree in ques- 

 tion is two years old, the seed having been planted in October, '87. 



Box elder trees of the same age showed an equal tendency of the 

 roots to penetrate the lower soil, though in box elder the tap root was 

 not so well developed, one of the trees dug having four deep-growing 

 lateral roots. 



Black walnut and honey locust of the same age had also grown 

 deep into the ground. The root of a hard maple tree which had a top 

 only eight inches high, was followed almost straight down for thiee 

 feet, where it was broken off ; but it had become very thin at that 

 point. Another hard maple and a black wild cherry had long roots 

 which only went about a foot deep, and then grew laterally. 



These facts are noted as refuting a statement very commonly 

 heard in Dakota: " Trees will not grow here because their roots do 

 not grow deep." In the case of box elder, white ash, black walnut and 

 honey locust, it is seen that two year old trees penetrate the ground as 

 deep in Dakota prairie as in any other soil. 



At the time of digging these seedlings, trees of the same sorts that- 

 had been set in the plantation in April, were taken up. A- fine growth 

 of fibrous roots was found, the box elder having made the greatest root 

 growth, closely followed by white ash. The ash trees had not devel- 

 oped a tap root, but the growth of fibrous roots was excellent, surpass- 

 ing the lateral root-growth of the two year old trees from seed. So 

 also the black walnut and honey locust, trees that develop a strong tap 

 root when grown from the seed, when transplanted made a fine growth 

 of fibrous roots, none of which seemed to follow the habit of tap roots, 

 In digging trees that have stood a few years after transplanting, deep- 

 growing roots are always found. This growth of fibrous roots the first 



