An Orchard Scourge. 205 



tious, it would not have been injured, so its own condition is the first cause 

 of the mutilation. The rabbit is only a secondary thing." I say no one in 

 such a case tries to indulge in such metaphysics. All admit the direct 

 agency of the animal in causing the mischief, because all are familiar with 

 the possibilities of those well-sharpened teeth, and all can clearly see their 

 imprint in the wound. There is no use of argument in this case. iBut of 

 these hypothetical fungi, of which nothing is known, whether good or evil, it 

 is not strange that people leave them out of the premises altogether in reach- 

 ing a conclusion. Without the compound microscope we are hardly aware 

 of their existence, and certainly must remain ignorant of their direct effects 

 and their methods of producing them. But, fortified and prepared with this 

 marvelous instrument and the proper ability to use it, these things disap- 

 pear. Then there is no important difference in what can be known, and 

 thoroughly known, between the methods and effects of these minute but 

 real, specific, self-nourishing and self-propagating things known under the 

 general name of Fungi, and that other specifically characterized thing called 

 rabbit. 



Having had abundant opportunity to observe, I have no hesitation in say- 

 ing that a certain fungus is the direct cause of the disastrous malady which 

 has so seriously injured the apple and pear orchards of our whole Northwest 

 during the last year. The rabbit itself is subject to conditions; its depreda- 

 tions in summer amount to nothing, so far as trees are concerned, and cer- 

 tain conditions of winter ruefully reduces their numbers. Our fungus is no 

 less, perhaps not more, subject to varying conditions of temperature, moist- 

 ure, etc., or in a word of environment. Its vigorous growth is impossible un- 

 der one set of these co ditions; it unduly develops under another combina- 

 tion of influences. But in the sense that the rabbit, and not the peculiarities 

 of the weather, is the direct cause of the gnawing, so the fungus, which has 

 been described, and not the rain, or the dew, or the sun, or the frost, is the 

 immediate agent of this scab and rust. 



It is, however, no new thing. It has neither come into existence in our 

 time nor has it recently been introduced in our part of the country. Its 

 dispersion over the world seems to be as wide as that of the apple itself, and 

 records now exist in the books of its occasional prolific development and in- 

 juries over nearly a century of time. Botanists have baptised it with several 

 names, hard enough of course, and collectors of specimens count it in the 

 make-up of herbaria, sometimes more than once, on account of the synony- 

 mical names under which it is known. Now, however, the authorities are 

 quite generally agreed that henceforth Fusicladium dendriticum , Fhl., shall be 

 its true and only title in scientific parlance. 



Turning now to the supposed conditions which have of late influenced the 

 increased injuries of the fungus, nothing can be asserted with positiveness, 

 but all indications seem to point to atmospheric and climatic causes rather 

 than any special physiological changes in the trees themselves. Some kinds 

 of trees are much worse affected than others, and this may be generally true 



