468 



THE CANADIAN HORTICULTURIST. 



ments thus far has been eight codling-moths 

 in fifteen nights. The wingless female can- 

 ker worm moths will not crawl into " moth- 

 catchers," and the lights do not attract the 

 two kinds of apple-borer beetles, the peach- 

 borer n-oth, plum curculio, or the saw-fly 

 of the currant-worm or pear slug. 



As trap-lanterns can have no effect upon 

 fungous diseases, they can never take the 

 place of the spray pump and Bordeaux mix- 

 ture. Experience^ has shown that several 

 trap-lanterns set very near every tree in an 

 orchard will not noticeably reduce the crop 

 of wormy apples, or diminish the number of 

 hungry caterpillars feeding on the buds and 

 leaves. 



There are instances in which trap-lanterns 



may prove useful, such as where some light- 

 loving insects becomes a pest in green- 

 houses, or in the case of some local pest 

 whose period of flight is sharply defined and 

 of short duration. But no one has yet con- 

 clusively demonstrated that any insect pest 

 can not be much more effectively and 

 cheaply combated in some other way than 

 by the use of "moth-catchers" or trap- 

 lanterns. 



The outcome of all the experiments made 

 everywhere renders it doubtful if these aids 

 help enough in our insect warefare to pay 

 for the trouble and expense of using them, 

 while they certainly do not warrant anyone 

 in recommending their use, or even pas- 

 sively permitting it without protest. 



APPLE SCAB FUNGUS 



IS ONE OF THE MOST DESTRUCTIVE 

 PESTS THAT COMES INTO ORCHARDS 



VERY few, except scientists, recognize 

 that apple scab is one of the most 

 destructive pests that comes into the orch- 

 ard of the apple-grower. The codling moth 

 is supposed to be far more destructive, but 

 such is not the case. Great precautions 

 are taken against the said moth, but little 

 or none against the apple scab fungus. 

 When a picker takes an apple from a limb 

 and finds a scab on it, he gives it not an- 

 other thought, for that is apparently only 

 a blemish. He imagines that he sees on 

 the apple all the result there is, and he con- 

 siders it not worth investigating. In fact, 

 this scab does most of its damage to the 

 foliage, and what appears on the apples is 

 merely its secondary work. By the work 

 of this fungus the entire tree is weakened, 

 and the apple crop is cut short year after 

 year. In addition to the fruit being smaller 

 than it should be, the apples fall early, as 

 the tree is too much weakened to nourish 



them sufficiently to induce them to hang on. 

 It seems that an apple hangs on just as 

 long as it is receiving nourishment. When 

 nourishment is cut off the apple automati- 

 cally detaches itself and falls. Anything 

 that causes a check to this supply of nour- 

 shiment leads to the fall of the apple. The 

 apple scab fungus, by sapping the strength 

 of the tree, brings about this result. An- 

 other indication of the presence of the fun- 

 gus is the fall of the leaves before their 

 natural time. This is brought about in the 

 same way as is the fall of the apple. The 

 nourishment ceases going to the leaves and 

 the stem begins to detach itself from the 

 tree. Thus long before the other trees have 

 dropped their leaves the tree that is badly 

 affected by the fungus named is bare. 



When a tree is badly affected it takes 

 more than one year to bring it back to a 

 normal condition of fruitfulness. Thus, if 

 a tree has the disease this year, the crop 



