The Lancaster Farmer. 



Pro£ S. S. EATHVON, Editor. 



LANCASTER, PA.. APRIL, 1875. 



Vol. VII. No. 4. 



COLORADO POTATO-BEETLE. 



« {Doryphora deeemlincata.') 



The accoinpanyiiiK liE;iiivs, wo tliiiik, suffi- 

 ciently illustniU' this iiuw notorious insect, in 

 its various stages of dcvolopment, without iii- 

 ttictiuf; upon our readers a tcelniical descrip- 

 tion of it. It may, liowever, Iw necessary to 

 state, Ijy way of simplilicatiou, that a a shows 

 the CfiRS. deposited in groups on tlie under- 

 sides of tlic potato leaves; and which, 

 when first deposited, are of a lemon 

 yellow color: 6, ?j, 'j, the hirnr, of vari- 

 ous ages, colors, oraiific and black; r, 

 thepi(jj((,a lit;ht clay yellow,and always 

 found under ground; d, (?, the hiuitjo, 

 or adult l)ectle, colors dark clay yel- 

 low and tilack; e, a wing cover, magni- 

 lied, illustrating itsspeciliclineations, 

 theother figures being the natural size; 

 /, one of the posterior legs. 



The most common translation of 

 the Latin name is " Tenlined Siiear- 

 man," y/hich. tptviJifdHi/ seemsobvious 

 enough, but i/oicriVd??;/ it would bedif- 

 Ikult to see anything aliout the insect 

 that conveys the idea of a spearman. 

 These figures, together with the living 

 forms, which are becoming familiar to 

 potato growers in Lancaster county, 

 will enable those to identify them who may be 

 yet unacquainted with their general appear- 

 ance. 



It seems hardly necessary to publish the his- 

 tory of the "Colorado Potato-Beetle" again 

 in the columns of The Faumek, and yet, in 

 view of the fact that it may come before a larger 

 nimiber of readers since " our new departure " 

 than it did in our former volumes, and that past 

 e.xperiences have had a tendency to direct the 

 attention of potato growers towards a more 

 thorough imjuiry than they have condescended 

 to bestow uiion it heietofore, it may not be in- 

 appropriate to reproduce what we have for- 

 merly written, with such modifications, addi- 

 tionsand corrections as subsequent experiences 

 seem to suggest. And again, notwithstanding 

 the floods of literature with which our country 

 is now almost everywhere deluged, it is some- 

 times discreditably apparent that a great many 

 peoplestill read •'little or nothing," and espe- 

 cially those who, one would think, have the 

 greatest interest in reading the practkal mat- 

 .ter that h:is appeared, from time to time, in the 

 columns of the agricultural, horticultural and 

 scientific journals of the country. Moreover, 

 if it requires periodical preaching, and thecon- 

 .stant illustration of "line upon line," and 

 "precept upon i)recept," to impress or remind 

 people of tlieir ridigions obligations, wecannot 

 reasonably expect that they will give heed even 

 to tluir material interests — especially where 

 reading is involved — without a reiteration of 

 our admonitions, in res|)ect to those things 

 which are likely to seriously ((/fWthose interests. 



In the spring of 1845 a friend of ours, hxtated 

 in Wisconsin, in the vicinity of Grand de Tour, 

 and him we had pri'viousiy commissioned to 

 collect for us the insects of that region. His 

 first instalment we received sometime during 

 tlie sunniier of that year, and among them were 

 four specimens of a large chrysomelan, which 

 we subse(iuently submitted to a competent 

 coleojiterist — for we then possessed neither de- 

 scription nor catalogue of American insects — 

 and hc> named them Poliiyramma W-lineaUi of 

 S.\Y, with juncta of Gekmek, as a synonym. 

 On a subsequent occasion we received two spe- 

 cimensof the same species,but somewhat larger 

 in size, from South Virginia. Allied species, 

 then included in the genera, lllephnridn, Lahi- 

 donifru, Zij(jn(jriiinmn and Cal'lijrnpha, we had 

 frequently found in Lancasterand York coun- 

 ties, hut we never noticed that any of them fed 

 upon the potato tops. Calliifrapha we gener- 



ally found most abundant on the dwarf willows. 

 For about fifteen years our groU|) of (^hry- 

 sonu'lans remained undisturbed, unlit the laie 

 lamented Mit. WAl.sii.of Hock Island. Illinois, 

 demonstratiMl tliat U)-linc(tl<i. Mid* iiiitft<t were 

 not .synonyms, but distinct; that those we re- 

 ceived from (irand dcTonraiid Virginia were 

 thi' junctit, and that h)-linii<i from (!ol<irado 

 and farther west, only reached Wisconsin, 

 Iowa and Illinois, about 18(jl or 1802. And 



that wherever they appeared they were par- 

 ticularly destructive to the vines of the common 

 potato, {Solanum tubcrosuni,) and since then 

 they have become a common pest. 



This enemy of oneof our most essential crops 

 having, to all appearance, now fixed itself in 

 Lancaster county, allow us to ott'ersome specu- 

 lations as to how it got here so far in advance 

 of its usual yearly progress through the AVestern 

 States. In 1S71 we heard of its being within 

 twenty miles of the western boundary line of 

 Pennsylvania; and as its previous progress had 

 been from sixty t(j .seventy miles a year, we 

 might naturally have looked for its "advance 

 guards "in this county, about the year IS7.") 

 or 187(). But it was here already in IS7-J, and 

 as its first appearance was in the vicinity of 

 the Pennsylvania railroad, there is reason to 

 conjecture" that it had been brought here some- 

 how on the rolling stock of that road. In 1870 

 a few of these beetles had been discovered in a 

 potato patch in the town of Worcester, Ma.ss., 

 according to Dr. Packard, who gave it as his 

 opinion that they had been conveyed thither 

 on the railroad, as the enclosure in which they 

 were discovered was in proximity to tlie road. 

 But through Yankee ingenuity and vigilance 

 they were exterminated. 



No\\', the last brood of the season of this insect, 

 either in its pui>a or mature state, hyljcrnates 

 during the winter sea.son — that is, l)ecomes 

 torpid — either under the ground, un<ler heaps 

 of field rulibish, or in " cracks and ci'cvices," 

 or other convenient hiding ))laces. In the 

 autumn of 1871 they were noticed near the 

 eastern boundary of Ohio, deserting a potato 

 field V)ecau.se no more potato plants wore in 

 their green or succulent slate, and winter was 

 approaching. Tliey were so nunurous in cross- 

 ing over the rails of the ro.ad, that the driving 

 wlieels of the engines would sometimes make 

 a whole revolution without making any for- 

 ward progress, in consequence of the cruslied 

 bodies of the insects lubricating the tracks. 

 AVe may, therefore, reasonably conclude, that 

 some of them took refuge in the rolling stock 

 standiiig on the road, or in exposed freight, 

 subsequently lo.aded on the cars — for even the 

 streets, sidewalks and yards of some of the 



*We are in possession of iltiislratioiisof tliisiiiseet, 

 and in a future nuinliernf our jnurnai we will publit^li 

 ttieni ami piiinl out the speejJie ilistinetions lietween 

 it and lO-Zute/d, auil also soniethinir alK)ut its -jreo- 

 trraphioal distribution, its history and its habits, fur 

 the edilication of our readers. 



towns, were full of them and thus were con- 

 veyed toother remote localities. It isditlicult 

 to comprehend how they could so soon have 

 crossed the Allegheny mountains, and have 

 reached ICastcrn Pemi.sylvania, on any other 

 theory. 



It is true that the matured beetles arc pro- 

 vided with ample wings, and although tlieir 

 flight is sluggish, they may still possess the 

 power of flying a great distance in calm 

 weather. Butterflies have an appar- 

 ently weak and awkward flight, anil yet 

 they have been known to alight on the 

 ■y^~J rigging of vessels ninety or a hundred 

 mihsoutalsea,iufair weather. Insects 

 of various kinds have fri'ipiently teen 

 known to cross the liritisli (^haimel, a 

 distance of thirty or forty miles from 

 the continent of Em-ope "to England, 

 and vice v< r.sn. This does not preclude 

 theiiossibilityof their being also trans- 

 ported by artificial means, and it was 

 evi<lently by such means that they were 

 first brought into Lancastercounty. 



Although potato growers are liegin- 

 ning to acipiirc a realizing sense of 

 their destructive habits, and to learn 

 Something of their individual identifi- 

 cation, yet there is a vast amount of 

 the most profound ignorance still 

 abroad in reference to their history, their trans- 

 formation, and their modes of reinvnluction 

 and [lerpetuation ; some alleging that the 

 " white butterfly" deposits the eggs from which 

 the disgusting grubs are hatched; others that 

 the grubs are the parents of certain plant-lice 

 which infest the potato vines; and others again 

 that when the female is d<me laying her eggs 

 she creeps into the groimd, and comes forth 

 again rein vigorate<l; many of them vigorously 

 warring against the grubs," but paying no atten- 

 tion to the mature beetles — the authors of the 

 pestilential hordes. 



Although the lives of virgin or gravid female 

 in.sects may be jirolonged to an iiulcfinite 

 period, yet when they have oviposited, they 

 usually .soon die thereafter from exhaustion. 

 As the female "Colorado Beetle" deposits 

 from one thou.siind to twelve hmwlred eggs 

 within a period of about forty days, there is 

 reason to believe that she .soon thereafter shares 

 the common fate. This is also the ca.sc with 

 the males after their sperniatozoic energies are 

 exhau.sted. Therefore those which survive the 

 hybernating period .and make their apj)earance 

 in early spring, are either gravid or virgin 

 female, and imexhau.sted males. We have seen 

 the .sexes in coin in the early |)art of .June, and 

 therefore concluded that they had hylH-rnated 

 in the pupa state; theearlier eggs must there- 

 fore have been from females impregnated la.st 

 year. 



Under these circumstances then, it becomes 

 the bounden duty of all tin- imtato growers in 

 a district infested by theColorado Potato Bee- 

 tle to exerci.se a vigilant watch for the.se insects 

 early in the spring, evcm tefore their potato 

 plants have broken through the surface of the 

 ground, and by careful and thorough hand- 

 picking or otherwise, to gather and destroy all 

 the adult Ix'ctles as soon as they make their 

 ai)i)earance; for in so doing they destroy from 

 ten to twelve hundred insects in embryo. 

 Although the beetles themselvesalsofeed upon 

 the i)otato plants, yet their injuries are only 

 as one to to a hundred, when compare<l tothe 

 injury inllicted by the larva. Butthe farmers' 

 labors in t his <lircetionsh(mld not ceiwe here, for 

 some of the insects may have evaded their ut- 

 most watchfulness. They should, therefore, 

 thoroughly examine all their potato plants, 

 and, if eggs are present, they will l)e found in 

 clusters of from twenty to iifty on the under- 

 sides of the leaves. 

 Thejse eggs are sufficiently conspicuous to be 



