392 



NEW ENGLAND FARMER, 



MAY ar, ig4o. 



From the Miildletown Constitution. . 



REMARKS ON THE CANKER WORM MOTH 

 Or Gioinetra Fernnla, and other Insects injxirioiia to 

 the Orchard and Forest Trees. Bv Joseph Bar- 

 BATT, M. D. Read before the Cuvierian Society 

 of the H'csleyan University, Miildlctoum, Jlpril 

 ith, ISiO, and published at their request. 

 During the last season, great damage was done 

 to orchards b}' the raviges of an insect generally 

 known by the name of tlie canker worm. In the 

 latter part of May, the orcliards looked as if they 

 had been scorched by fire. The extent of injury 

 done to the crops of fruit i;: too well known to re- 

 quire any notice here. With a view, however, of 

 gaining all the informati.jn on the subject, we then 

 watched the progress of the canker worm, through 

 its different stages, and have had our attention 

 drawn to these troublesome and destructive pests of 

 the apple and elm trees: they have since appeared 

 in gre"><- n'lmbers. In turning to works on farming, 

 as well as to books on agriculture and orchards, 

 relating to North America, there is such an evident 

 want of exact knowledge in the names of the in- 

 sects intended, that it necessarily leads to much 

 misapprehension and confusion: it was thought, 

 therefore, that an acceptable service would be ren- 

 dered to our farmers and others, by giving the sci- 

 entific namei of ii;sccts, as found in books ir.d cat- 

 alogues on entomology, especially the valuable 

 catalogue of the insects of Massachusetts, drawn 

 up by Dr Harris, and published with the report of 

 the geology of that State. 



The canker worm is said to have been first ob- 

 served in New England in 1666, and in different 

 years it has been found very destructive to orchards, 

 and then for a time, from unknown causes, to have 

 disappeared. In 1808, they became troublesome 

 again in Middlesex county. 



'I he apple it will be recollected, is an imported 

 tree, and by some it has been supposed, the canker 

 worm is also of foreign origin. If^this should prove 

 to be the case, it must not be forgotten that several 

 insects very destructive to the timber, and formerly 

 confined to the American forest, have in turn found 

 their way to Europe, and become very injurious to 

 tlie growing timber there. Professor Peck, of Cam- 

 bridge, wrote an essay that was published in 17!)7, 

 on the Geomelra vcrnata, or canker worm moth. 

 This essay received the prize of the Massachusetts 

 agricultural society, ($50,) and was published in 

 their papers. We have not been so fortunate as 

 to obtain a copy of this e.ssay. 



The moth of the gcometra vernata is'seen in its 

 perfect state in spring, when it rises froi:i the earth. 

 The female of this, as well as of some analogous 

 species, has mere rudiments uf u-inffs. The Pha- 

 lena brumalis, as its name imports, appears only in 

 winter (in Europe.) This peculiarity retards the 

 progress of the geometra vernata through a country, 

 and it is owing to the wingless insects being oblig- 

 ed to crawl up the tree, that a belt of tar serves for 

 a time effectually to keep trees so protected clear 

 of them. The male insect, it is true, is provided 

 with well developed wings, but as they generally 

 ascend the tree with the females, they are as readi- 

 ly destroyed as the other kinds. 



In consequence of the early breaking up of the 

 winter of 1840, there being but little frost in the 

 ground, the moths showed themselves on tarred 

 trees of elm and apple very early. From the 20th 

 «) Ecbri:ary to the ;3d and 4th of March they were 



numerous: the cold weather of the 5th kept them 

 again in check for a short time. 



In the ground they occupy an area of the extent 

 of the tree on which they fed the preceding year as 

 larvae or caterpillars. 



The Hon. H. A. S. Dearborn, formerly President 

 of the Massachusetts Agricultural Society, made a 

 series of observalions admirably conducted in the 

 year 1830, on the cahker worm moth. Ho com- 

 menced his operations by tarring on the 4th of 

 March, in his orchard, the apple, quince, plum, ap- 

 ricot, cherry, and elm trees, with the honey locust, 

 having found all these subject to its attack. As 

 the weather continued cold and the ground frozen 

 for some days, the moths did not show themselves 

 that year till the ]3th of March ; and on the even- 

 ing of the 16th, the female moths b."gan to ascend 

 the trees in considerable numbers, as well a.^ on 

 the following nights, (with some exceptions, owing 

 to the state of the weather,) until the SOth and 21st, 

 when innumerable males came forth, previous to 

 these last days, but few '~;:d been seen. On the 

 23d, both male and female moths were so numerous 

 as to bridge over a belt of tar by 8 o'clock, that 

 had been applied tiie same afternoon, and it became 

 necessary to renew it at night. The moths of both 

 kinds continued to ascend the tree till April 8th, 

 with but few of the females during the last period. 



The eggs laid by the moths began to hatch April 

 30th ; they continued to prey on the leaves tillJune 

 5th, when the small caterpillars or worms com- 

 menced descending by delicate threads and entered 

 the earth : this they do in the night season. It 

 was found by Mr Dearborn that the caterpillars of 

 the geometra vernata left tlie trees on the .^th, 6th, 

 and 7th of June, and it was difficult to find one the 

 8th. On examining the earth beneath the trees, 

 he found they had penetrated from 1 to 3 inches 

 below the surface, and they had all changed to the 

 chrysalis state, by the 4lh of June. 



The geometra vernata sometimes makes its ap- 

 pearance in the autumn as well as in spring; they 

 then deposite their eggs, which hatch about ihe 

 same time with those laid in spring. They were 

 observed in the month of October 1831, in the vi- j 

 cmity of Boston, and the writer )iad also seen them j 

 in autumn. The winters of 1830 '31 being mild, 

 they were observed ascending the trees every month. | 



Dr Harris, tiie celebrated entomologist of Bos'on, 

 supposes the geometra vernata may bo identified 

 with the phalena brumata of Linnteus, or winter j 

 moth of Europe. It is thus described in Rees' Cy- i 

 clopedia : phalena brumata — wings yellowish with 

 a black streak, and paler behind: the female is j 

 apterus (without wings) and of a brown color. , 



We do not, however, find in English works on ! 

 insects, any|notice of its ravages in orchards siiiii- ! 

 lar to what takes place in this country. The ap- 

 ple tree is invested with the larvse or caterpillars of! 

 several insects ; and especially with a caterpillar 

 that is troublesome and voracious, the product of a 

 different moth. 



Before closing these remaiks on the geometra 

 vernata, it may bo well to name here (to avoid con- 

 fusion) some other insects that infest the apple tree. 



Every tree or plant is more or less infested with 

 insects, and tlie fiirest trees as well as those of the 

 orchard, are at times attacked by numerous cater- 

 pillars: a little attention in spring will generally 

 be sufficient to destroy the nest of the tent-making 

 insect, generally known as the caterpillar. This is 

 the larvae of the Clisiocampa castrensis, an imported 

 species. This is the most troublesome to orchards 



in England; but is not to be named with the geo- 

 metra vernata or canker worm, for the desolation it 

 has caused in this vicinity, as well as through dif- 

 ferent parts of the northern States. 



Among the insects that infest the leaves of the 

 apple tree, may be named several kinds ai Aphides, 

 and also a caterpillar that preys on the bark, and 

 which changes to a moth called the Tinea corti- 

 calis. 



The Torlix ponionii or apple worm, also feeds in 

 the centre of the apple, and beside causing its pr'-- 

 mature fall, is productive of much injury to the 

 fruit. The last named insect should be well known 

 to orchardists in all the stages of its existence, as 

 well as the means that have been adopted for eradi- 

 cating it. 



It gives us much satisfaction to learn that Mas- 

 sachusetts, in her most valuable and ably conduct- 

 ed State surveys, has, besides furnishing an exten- 

 sive and valuable catalogue of insects, caused a 

 work tj be drav.n up expressly on the insects inju- 

 rious to agriculture, &c. with the details of the 

 most effectual means yet known of destroying them. 

 T his work undertaken by Dr T. W. Harris, will 

 soon we learn be printed, and it should be exten- 

 sively circulated. 



The work would be more directly useful to the 

 public, if it contained figures, in the manner of 

 some of the admirable British publications on ento- 

 mology, or similar to that beautiful work, the En- 

 tomologist's Text Book, by J. O. W estwood, F. R. 

 S., 12 mo., London, pp. 429, with colored plates ; 

 or the excellent and popular work in 3 vols, on in- 

 sects, with figures, forming part of the series of 

 the Library of Entertaining Knowledge. These 

 works should have a place in every public library 

 and lyceum, and there ought besides to be preserv. 

 ed, collections of insects, especially those that are 

 destructive to the fruits, &c. If these' measures 

 were duly attended to, young persons would soon 

 attain a competent knowledge of these depredators, 

 that arc at this time doing extensive mischief to 

 the orchards, fields, gardens and forests of our coun- 

 try. 



It has been estimated that in one county in Eng- 

 land the injury done to the turnip crop alone by a 

 small fly, the Hallica memorum or turnip fly, in De- 

 vonshire in 1786. amounted to £100,000 sterling. 



A farmer in the county of Middlesex stated to 

 us a short time since, that his orchard, which used 

 to yield liim 500 barrels of cider annually, did not 

 last year yield a single apple ! If we may judge 

 from what we have w itnessed the last two jears, it 

 would seem that the a4jple -trees would be destroy- 

 ed, at least those in which the insects are suffered 

 to have their course. The locust tree in some of 

 the northern Stales is now so much infested with a 

 boring insect, the Clytus piclus, as to be useless, 

 and to be rendered even a nuisance. 



The black walnut tree in some places is so much 

 frequented year after year by numerous caterpillars,- 

 that trees have been cut down to avoid these pests. 

 • The elm tiesides being preyed upon by the can- 

 ker worm, is attacked by another insect, the spiny 

 caterpillar. This proves to be an introduced spe- 

 cies ; and as there are some facts in relation to it 

 of interest to the entomologist, we will give it a 

 passing notice. In Europe it is known to feed up- 

 on the birch, poplar and willow, but in this country 

 it deserts the poplar and feeds on the willow and 

 elm. About the 15th of June these large and spi- 

 ny caterpillars are seen in numbers to quit the elm, 

 an I by the 30th of the same month, they are abroad 



