SUPPLEMENT 



The Comparative Value of Bark as a 



Surface Mulch for Apples, Blueberries, 



and Raspberries 



By L. PHELPS LATIMER 



Associate Horticulturist 

 New Hampshire Agricultural Experiment Station 



Apples 



IT is standard orchard practice in the New England states to grow apple 

 trees under a sod-mulch system, placing additional hay or other suitable 

 mulching materials on the ground beneath the spread of the branches of 

 the trees in order to control weed growth, improve the physical condition 

 of the soil, conserve moisture, and supply mineral nutrients. Cultivation is 

 thus eliminated. Hay has been considered the best material for this purpose. 



The purpose of this experiment was to determine the value of bark com- 

 pared to hay as a mulching material in the orchard. Three separate blocks 

 of trees were utilized, and the tests were started in the autumn of 1950 

 as follows: 



1. 32 five-year-old Mcintosh at Durham. 



2. 25 seven-year-old Mcintosh at Durham. 



3. 120 three-year-old Virginia Crab and Robusta No. 5 apple 



stocks at West Stewartstown. 



In the experiment at Durham, old softwood bark was compared with hay 

 as mulch; at West Stewartstown, old softwood bark and new softwood bark 

 were compared with hay as mulch. The criteria for measuring the response 

 to different mulches were annual twig growth in all blocks and, in addition, 

 yield of fruit in Block 1 (at Durham). 



Since the difference in twig growth between treatments was not stastically 

 significant at the 5 percent level, the data taken at Durham indicate that 

 the bark-mulched trees compared favorably with hay-mulched trees in termi- 

 nal growth. At West Stewartstown there seemed to be a tendency for hay- 

 mulched trees to make slightly greater terminal growth than those mulched 

 with either new or old softwood bark. On the other hand, trees mulched 

 with old softwood bark made growth equal to that produced by trees mulched 

 with new softwood bark. 



18 



