MAINE APPLE DISEASES. 343 



This orchard was badly injured, particularly on the north and 

 northwest sides of the more exposed trees and in the direction 

 from which come the prevailing cold winds of winter. A nat- 

 ural wind-break of evergreens and coppice growth was situated 

 so as to protect a portion of the trees and here the injury was 

 much reduced or absent altogether. 



Aside from the possible value of planting wind-breaks very 

 little can be done to prevent winter injury in orchards already 

 planted except to provide artificial drainage where necessary 

 and to avoid forcing the trees to too luxuriant and late growth 

 during the latter part of the season, as has already been men- 

 tioned. However, much of the ill effects following an adverse 

 winter may be eliminated by proper attention to the injured 

 trees. Observations made in Maine orchards for 4 seasons 

 following the winter injury of 1906-07 have convinced the 

 writers that as much if not more damage has occurred indirectly 

 from the attacks of fungi following the winter injury and which 

 gained entrance through the wounds thus made than as a direct 

 result of the winter injury itself. In many cases very little was 

 done to remove the injured parts and they were allowed to 

 decay and serve as breeding places for wood destroying fungi. 

 Later this decay followed back along the injured limbs or into 

 the interior of the trunks, resulting in the death of the entire 

 tree. 



"While severe pruning and cutting back immediately follow- 

 ing winter injury is not advocated, all dead wood should be 

 cut out as fast as seen and the wounds at once covered with a 

 good liquid grafting wax or two or more coats of pure white 

 lead in boiled linseed oil, and then repainted as frequently as 

 necessary to keep the wounds well coated till they are covered 

 with the new growth.* The dead bark on trunk and crotch in- 

 jured areas should be removed back to healthy tissue and the 

 wood thus exposed kept well covered with grafting wax or pure 



* In some instances severe injury to the trees has been reported 

 where the entire trunks have been heavily coated with lead and oil, to 

 prevent insect attacks. This may be due, however, to the use of impure 

 lead and either unboiled oil or some substitute for linseed oil. In the 

 writers' experience, and so far as can be learned, the use of pure white 

 lead in boiled linseed oil has been universally successful in treating 

 wounds made in pruning. 



