MAINE AGRICULTURAL EXPERIMENT STATION. 191O. 421 



of apples are susceptible to spray injury, or bordeaux injury 

 as it is frequently called, especially if rainy, damp or cloudy 

 weather is experienced at or immediately following the applica- 

 tion of the spray, has been held responsible in a considerable 

 measure for the lack of more general adoption of spraying by 

 Maine orchardists. In too many cases the fact that many varie- 

 ties (see list on p. 389) are seldom, if ever injured by bordeaux 

 mixture has been entirely overlooked. Neither has it been 

 understood that the danger from bordeaux mixture can be min- 

 imized largely, in many seasons, by applying the spray only dur- 

 ing periods of bright, sunny weather, and avoiding its use, if 

 possible, when there are several, successive, cloudy, rainy days. 



However, there has been and is a demand for a fungicidal 

 spray which will control the various plant diseases and still cause 

 no injury to the foliage and fruit of the more tender varieties. 

 Experiments begun by Scott* in spraying apples and peaches, 

 the latter being very susceptible to bordeaux injury, and later 

 taken up by others in various parts of the country, indicate that 

 in the different lime-sulphur sprays we have the promise of 

 something which may control certain of our orchard diseases 

 nearly if not quite as well as bordeaux mixture and if not used 

 too strong be practically free from the production of spray 

 injury. 



Therefore, it is recommended that all orchardists who have 

 experienced trouble with bordeaux injury in the past, and others 

 who wish to spray varieties which are known to be susceptible 

 to spray injury, give the lime-sulphur treatment a thorough trial. 

 It will be noted, however, that lime-sulphur as suggested for 

 summer spraying for fungous diseases is used in a much more 

 diluted form than for winter spraying for insect pests. The 

 more concentrated sprays are far too strong to be used on the 

 tender foliage and fruit. 



The above recommendation should in no ivay be construed 

 as advising against the use of bordeaux mixture where it has 

 always been used zvithout injury in the past or with those varie- 

 ties of apples zvhich the experience of others indicates that there 

 is little or no danger of bordeaux producing any injurious effects 

 on the fruit or foliage. Apple scab is the greatest factor to be 



* Scott, W. M. Self-boiled Lime-sulphur as a Promising Fungicide. 

 Bureau PI. Ind., U. S. D. A., Cir. i, pp. 1-18. 1908. 



