PROCEEDINGS OP THE ANNUAL MEETING. 275. 



EXPEPJMENTS WITH ORCHARD COVER CROPS. 

 BY PEOF. JOHN CRAIG OF OTTAWA, ONTARIO. 



Suitable cover-crops to protect orchards are of great importance in all 

 fruitgrowing sections. In northern regions, the practice of sowing a 

 crop after cultivation ceases, that will at once enrich the soil and pro- 

 tect the feeding roots of the trees, is one of the essentials to success, 

 and an item in the annual programme of orchard management that 

 should never be omitted. The late P. 0. Dempsey of Trenton, Ont., 

 one of Canada's most successful fruitgrowers, recognized the truth of 

 these statements years ago, and frequently expressed himself to the 

 effect that a cover-crop of weeds in the autumn was far better, consid- 

 ered in the light of what w^as best for the trees, than no cover-crop at 

 all. The healthy and profitable orchard of apples and pears which he 

 left to his w^orthy son, W. H. Dempsey of Trenton, furnishes ample proaf 

 of the benefits of the system. 



Ill brief, this means sowing a crop in the orchard after cultivation 

 ceases in summer, that will protect the roots of the trees by preventing 

 at once alternate freezing and thawing and deep freezing; that will add 

 something (the more the better) to the fertility of the soil when turned 

 under; that will improve its tilth or mechanical condition, and, lastly, 

 that will occupy the ground to the exclusion of such plants as may- 

 wander out of place — w^eeds. 



When soils, especially those of a clayey nature, are constantly culti- 

 vated without being subjected to the ameliorating influences induced by 

 producing some kind of vegetation, not only do they become mechani- 

 cally unfitted for the production of healthy and vigorous plant growth, 

 but the plant food may take on forms not readily assimilable. In north- 

 ern sections, perhaps one of the strongest reasons that can be urged in 

 favor of the practice is the protective influence cover-crops exert against 

 the often severe root injury wrought by sharp frosts to trees growing 

 upon bare soil. Speaking of injury of this kind. Prof. Hartig of Ger- 

 many says: 



''Roots of all young trees, even forest trees, may be killed if severe 

 and long-continued frost finds the lighter classes of soil unprotected by 

 snow or any other covering. The periderm of the root is thinner than 

 that of the stem, and consequently the former is less protected; and, 

 moreover, growth is active for a longer period in roots than in the twigs. 

 When, in mild climates, growth continues till the middle of Miuter^ 

 when frost occurs the tissues are not in the inert condition which assist 

 them to resist cold, and death to the affected tissues follows. Such 

 plants burst their buds in spring but wither whenever transpiration from- 

 the delicate young shoots has exhausted the stock of water." 



An occurrence of this kind may wipe out in a single winter what was a; 

 promising young orchard. As the trees grow older and become deeper 

 rooted, the danger naturally lessens. Portions of the central experi- 



