THE PRACTICAL ENTOMOLOGIST. 



[From the AVestcrn Rural. Jiuio 2:;, ISCC] 

 The Canker Worm. 



Office op State BoAnn of AGRiccLTunE, 1 

 Lansing, Mich., June 11, 1866. J 



I yisitcd Calhoun county last week, chiefly for 

 the purpose of ascertainini^ the condition of the 

 canker-worm colony, near Marshall, about which I 

 wrote you a year ago. 



The orchards where, I saw the worms last year 

 are still infested, and they have also appeared this 

 year on several orchards where they had not been 

 seen before; but where ih'y prevailed in the great- 

 est numbers in 18G4: and 1865, they are less nu- 

 merous this year. The cause of their diminution 

 in their old haunts, is obscure. It is possible that 

 in some instances the ground was over-stocked last 

 year — that is, the foliage was not sufficient to carry 

 to maturity all the worms that fed upon the trees 

 — and that many of tbe starved larvre died before 

 they reached the perfect state. It may be that the 

 frosts and unusually cold weather which occurred 

 last Spring, soon after the insects hatched, destroy- 

 ed many of them. 



I could not learn that means either of destruc- 

 tion or prevention had been much used. Edwin 

 Wilson, of 3Iarengo, whose orchard has suiTered 

 most, dug the earth away from the trees last Fall, 

 after the ground had been somewhat frozen, and 

 put round each tree about a peck of strong wood 

 ashes, which lay there till the trees leaved out, last 

 Spring, when they were spread about. It was sup- 

 posed that the ashes had killed the insect in the 

 pupa state, to some extent; but it docs not appear 

 that the decrease in the number of worms this year, 

 as compared with the last, is any greater in this or- 

 chard than in others where no ashes, or anything 

 else, were applied. 



Gideon Towusend, of Marshall, whose fine or- 

 chard was Completely defoliated last year, put 

 round his trees in the Spring of 18G5, a good mulch 

 of straw as a manure for the trees. He allowed 

 Bwine to run in the orchard in the Fall, and they 

 rooted in the straw almost constantly. His poultry, 

 too, — barn-yard fowls and turkeys, — Were busy day 

 after day, scratching in the straw and earth about 

 the trees, from which they appeared to obtain food 

 which they liked much. It is probable that the 

 pigs and poultry devoured many canker-worms in 

 the pupa state. The worm, as it drops from the 

 branches to secure for itself a lodgement in the 

 ground, where it may undergo its transformation, 

 generally moves towards the tree, so that the chry- 

 salides are chiefly formed within a comparatively 

 small distance from the trunk. 



Effect of the yVorm, on the Tree. — It is plain that 

 the fate of trees whose foliage is year after year de- 

 stroyed by this insect, is to be the same here that 

 it has been elsewhere — it is death. People seem 

 to have been slow to believe this. They saw their 

 trees, whoso leaves had all been eaten by the can- 

 ker-worm, put forth anew set; sometimes they had 

 a few unseasonable blossoms which were followejl 

 by worthless fruit, and from this show of life and 

 vigor, it was inferred that the trees were not m^jj^ 



injured. But experience dissipates this hope, and 

 proves that the apple tree furnishes no e.xccptioa 

 to the rule, that plants long deprived of their leaves 

 must die. 



Two or three trees in Mr. Wilson's orchard, on 

 which the canker-worm first appeared, are totally 

 dead — the bark cleaving from them in strips. 

 These were first attacked in 1862. I was informed 

 last year that it was in 1863, but this was a mis- 

 take. Several other trees, some of the largest and 

 best in the orchard, are nearly dead — will inevi- 

 tably die this season. In fact, the vitality of all 

 the trees is so weakened, that thongh on many of 

 them there are not worms enough this year to do 

 much injury to the foliage, they will bear no fruit. 

 3Iany of the best trees in Mr. Townsend's orchard 

 show that they are fatally injured, and this will 

 soon be the result wherever the insect has establish- 

 ed itself, unless preventive measures against its 

 attacks are used, or some nnusual causes should 

 greatly diminish its numbers. Its ravages are now 

 obvious in at least six difierent orchards, and it is 

 spreading year by year. It should not be overlook- 

 ed, that according to information published by Mr. 

 Lyon, of Plymouth, through your columns, the in- 

 sect has appeared in other localities in the State. 



What shmdd he done? — This important question 

 may be answered by saying : — Adopt the best 

 means of preventing the female insect from ascend- 

 ing the tree. Various contrivances have been in- 

 vented for this. In my Keport for 18G5, as Sec- 

 retary of the Michigan State Board of Agriculture, 

 I have given an article on this insect, with figures 

 of it in various stages, together with descriptions 

 of apparatus for protecting trees. A cut is given 

 (at page 27) of " Merritt's Patent Tree-Protector," 

 made and sold by the American Tree Protector 

 Company, No. 19 Phoenix Buildings, Bo.ston Mass., 

 from whom a pamphlet may be obtained gratis, on 

 application, giving a particular description of the 

 apparatus, and directions for applying it. 



I have not yet learned the full results of last 

 year's experience at the East with the difi'erent 

 "Protectors," but I intend to obtain as correct in- 

 formation as practicable on this subject, and when 

 it is obtained, I will lay it before your readers. 



Next Fall and the early part of Winter, if mild 

 weather should occur after the ground has been 

 frozen, will be the time when the trees should be 

 protected against the female canker-worm in its 

 perfect state. It may be that, as last year, the in- 

 sect may not be matured at the time mentioned ; 

 but the trees should be protected as a safe-guard ; 

 and the protection should be continued until the 

 running season of the insect in Spring is over. It 

 should, therefore, be kept constantly in mind that 

 the coming fall is the time to begin the defence 

 against this dangerous enemy. 



And here it may not be inappropriate, to use a 

 word of caution against the use of alleged remedies, 

 which either do no good, or are worse than useless. 

 Of this character is the putting of sul]ihur into the 

 trunk of the tree, to juo)so« the canker-worm and 

 other insects. A prescription of this kind goes the 



