I l8 AGRICULTURE OF MAINE. 



These and other relatively unfavorable results with the ordi- 

 nary methods of orchard tillage suggest the advisability of shal- 

 lower plowing over tree roots, — not deeper than four inches at 

 the most,— and where the conditions permit, it would seem 

 advisable to displace the plow entirely, either with a double- 

 action disc or cutaway harrow, or with a satisfactory mulch. 



IS FERTILIZATION MOST EFFECTIVE ON TILLED OR UNTILLED 



TREES ? 



Judging from the Fassett experiment alone, one would 

 answer this question positively in favor of the latter trees. In 

 Table X, for example, the addition of manure to the tillage and 

 cover-crop treatment has resulted in a gain of only 37.6 bushels 

 per acre, while the corresponding gain from its addition to the 

 mulch is 190.7 bushels or over 5 times the gain secured by 

 manuring the tilled trees. With the commercial fertilizer simi- 

 larly, the gains from its use on the tilled trees are but 27.6 bush- 

 els annually, while the corresponding gains are 116. i bushels 

 on those receiving the mulch. These cases are, therefore, evi- 

 dently on the side of greater efficiency from the fertilization 

 applied to untilled trees, and incidentally it may be noted that 

 the thinner mulch under these larger trees shows none of the 

 interference with fertilization noted above in the experiments 

 of Table V. * 



Similar inference may be drawn from the large benefits 

 obtained from fertilization in our untilled fertilizer experiments 

 in the Johnston and Brown orchards,* as compared with the 

 smaller benefits obtained in other similar experiments involving 

 tillage. Such comparisons, however, are naturally much less 

 direct and less exact than those in the Fassett orchard. 



In Table V, on the other hand, with the exception of manure 

 on sod, we find that the largest increases in yield have regularly 

 come from the fertilization applied in connection with tillage, 

 and the differences are especially marked in Experiments 217 

 and 218. In Table VI, similar results are apparent in regard 

 to growth, — the most striking gains from fertilization in this 



* The fertilizer experiments in these orchards are discussed in the 

 paper preceding. 



