The Lancaster Farmer 



Prof. S. S. RATHVON, Editor. 



LANCASTER, PA., MAY, -1875. 



Vol VIL No. 5. 



THE COLORADO POTATO-BEETLE. 

 (Doryphora decemlinealu .) 



At the coiK'liision of our inipcr on tins insect, 

 in the Ain'il nuiulicrolTiiK K.mj.mhi;, in wliirli 

 we atti'iniili'd to i^ivi' an account of tlic most 

 conunon )iiniiiiiil an 1 nrlifiriid rcuifilics for its 

 (Icsti'Uction, \vc promised to continue the sul)- 

 ject in a pajier on iiii/KaW reuicilies. and in do- 

 in;; so we will mainly reiiruduee what we had 

 previously published, whidi, with the aid of a 

 few illustrations, we think will assist our read- 

 ers ill recoLTniziu'; them when they lind thcni 

 in their potato lields, or elsewhere, and enable 

 them also to make that discrimination to which 

 wehavealludedon various occasions, and with- 

 out which the polato-firowers will lie standiuD; 

 very much in their own li^iit. The utility of 

 pvcdaceoux and jxtrasilir insects, as destroyers 

 of the noxious species, is becominj; every day 

 more manifest, and intelligent farmers every 

 where are bei^inning to look more minutely 

 into these thinj^s as suhjecls more or less con- 

 nected with their material interests. Asa very 

 striking and lioiieful exaniiile of the utility of 

 tttttin-o} remedies, we liave jnst received from 

 Huntingdon conntv, I'a., about twenty c/nv/.s- 

 nlids of tlic "White Calibage ]5utlerlly', " 

 [I'ieria r(qifi') every one of which was infested 

 with a small Ilymenopterons parasite, to 

 which we will allude specilieally in another 

 place, in tliis number of oiu" journal. In 

 continuation of our present sut)ject, we 

 may say that where ignorance does not 

 prevent the free exercise of tliese remedies, 

 the labors of the fanners and their families 

 might be much lessened. fSomeof these natural 

 remedies are, however, only temporary; but 

 others, to a limited extent, are constant. It is 

 not known that birds, asa geiu'ral thing, mani- 

 fest any partiality for these insects, and this is 

 also the case with poultry in general. But we 

 liave lieen informed that ijuinni foirU are par- 

 ticularly fond of them, and probably would 

 continue to feed upon them, until they had 

 a surfeit of thenf. Tm-k-ei/s, both the adults 

 and the young, but especially tlie latter, are 

 said to t)c fond of them. 



Diirk-.s have been instructed to feed on them, 

 and in some instances chickens also; and last, 

 . perhaps not least, conies a report that a far- 

 mer in the vicinity of Kli/abethtown saved 

 his potatoes last year from destruction, liy per- 

 mitting a tlock of tame yiesr to enter his en- 

 closure daily, and that these, liirds became so 

 fond of the insects that they every morning 

 returned to the feast with renewed zest. Hi.s- 

 tory says that on one occasion a Hock of geese 

 saved ancient Rome from impending ruin, and 

 if they can now save the potato croj), they will 

 be entitled to a higher niche in the Temple of 

 Fame, or in historic record, a larger page. It 

 may be well to .say here, however, that it would 

 not be wise to iiermit fowls of any kind to enter 

 an enclosure where Paris green, or any other 

 poison, has been used. 



In papers published a year ago, in the Daih/ 

 E.c}irisx, the J)iiihj Intrlhijcncrr. and the Morn- 

 m<i Jierirw, of this city, we illustrated the 

 piissibh increase of this insect, whcrenomanual, 

 artilicial or natural remedies intervened to 

 check its progress, and where all other circum- 

 stances were eipially favorable; an<l the fact 

 that it does not so" increase, is largely to be 

 attriVnited to the existence of many natural 

 enemies to which it is constantly falling a prey, 

 and without which our highest estimates might 

 be realized. 



Enemies to the Colorado Potato Beetle. 



The first of the.se enemies is a two-winged 

 fly (Li/ilella dori/plwra, Fiij. 1,) a quarter of an 

 inch in length, and half an inch across the 

 expanded wings, of a black and silvery gray 

 color, the larva of which burrows into the 



larva of the |iotato be<'tle, and makes it an 

 iniwilling but certain victim. 



but the cros.slines 

 natural length and 

 Thi.s tly, acc(jrding 



This figure is magnilied 

 at the bottom, exhibit the 

 expansion of the wings. 

 to Prof. 

 It i 1 e y — t o 

 whom sci- 

 ence and 

 economic 

 agri(adlure 

 are indebt- 

 ed for the 

 develop- 

 ment of its 

 h ist ory — 

 d(!liosits its 

 eggs on the 

 soil body of 

 the tarivi of the potato beetle ; and when the 

 eggs are hatched, the little "maggot" pene- 

 trates the skin of its host, and fecils uiion the 

 internal sulistance of its body, and continues 

 there, " waxing fat" and i)rosperiug generally. 



■When the larva of the potato beetU' enters 

 the ground to assume tlu' puj}!) form, it carries 

 the i)arasite with it; and whether it is able to 

 effect its pupal change or not, it is all the 

 same, for — 



"Dcatli is written in its face, 

 And sorrow's in it. dwelling," 

 and instead of a living Donjphorii coming 

 f(jrth, a Lijdilht rises from its ashes, to tlii' 

 great joy of the fainier, and the overthrow of 

 one of his most destructive in.sect foes. 



Then we have at least four species of "Lady- 

 biids," the larva of which feed upon the eggs 

 of the potato beetle. Almost everybody 

 knows what a Lady-bird is, but not every one 

 knows its lizard-shaped larva, variously col- 

 ored with pink and black, and orange sjiots; 

 for we have seen those who were crushing the 

 Colorado larva, including these u.seful little 

 friends in their list of proscrii)tions. 



Fig. 2 represents the 

 "Convergent Lady-bird" 

 Ilippodnmia corcrijoiK) a, 

 the larva, b, the i)upa and 

 c, the perfect beetle, the 

 colors of which are Itlue, 

 orange, orange-re<l and 

 black, with a wliite margin and sjiots on the 

 tliorax of the beetle. Some years ago, when 

 the "Oat-aphis" (Apiliis av(na) devastated the 

 oat crop of Lancaster county, W'e foimd this 

 species very alaindant, regaling themselves on 

 the soft bodies of the a])hids. It is now found 

 to be equally as fond of the egg of the potato 

 beetle, and "feasts sumptuously every day" 

 on them, both in the larva and the perfect 

 state, and as it undergoes all its transforma- 

 tions on the vine, it is always conveniently on 

 hand. 



Fiy. :! is the "S^iotted I-ady- 

 bird," {Hippridmiiia niarnhitit) col- 

 or, deep pink and black. This ison(^ 

 of the most successful hyhernating 

 insects that we know of, having 

 found from three to live bundi ed of '^"/- •*• 

 them in a single nest, niuler bark, in early spring. 

 They are, however, not exclusively canni- 

 bal in their habits, for wc have freipiently 

 found them abundant. on the flowers of the 

 "butter-cup" (^'((nviK-uhix) feeding on the pet- 

 als, jiistils and stanK'Us. They are now known 

 to destroy the eggs of the potato beetle, and 

 that fact alone is worth all the butter-cups in 

 Christendom. 



Two other Lady-birds, of the same cannibal 

 habits, are known to feed on these eggs; 

 namely, thc"nine-spotted"(Oir(ii, (7/(1 0->!o((((rt) 

 and the " thirl een-dotted" (I{ippndamia 13- 

 jiunrtid"). These two we found nmnerous in 

 potato flelds last summer. Of course, ajiplied 

 Paris green would be equally as fatal to them 



^-y..5. 



as it is to the Culnrado pest, but here no dis- 

 crimination can be made; but many <if those 

 who depended on hand picking crushed both 

 friends and foes together. 



The "."opined soldier bug" {Armaapino8a,sc^ 

 Fig. 11) belonging to the order IIkmiI'TKKA, 

 also feeds exlciisivily upon these potato pests, 

 and not only on these alone, but also on other 

 noxious in.sects. Helonging to the same order 

 are three other true ';»</.< which feed on the 

 potato beetle, sucking out their substance and 

 leaving little more than the empty sludl or 

 skin, namely: the "Bordered soldier buf;," 

 not conunon in this locality, but farther soutli. 

 The "Many Handed Kobber" [Jlarprctor 

 cinrtus), the "Rapacious soldier bug" illcdtir 

 viits raptat'iriu.s, Fig. 4), with whose peuHra- 

 timj haliits we were made ac(iuainted many 

 years ago, and a few others have been known 

 to attack and destroy the larva of the potato 

 beetle in other localities ; therefore we may 

 count iqion their a.ssistance here. 



In addition to the foregoing, 

 several other species of biiij.i 

 have been discovered perform- 

 ing the same n.seful service; 

 conspicuously amongst them, y 

 here in Lancaster county, is the 

 "Wheel-bug" (Krrnrius iiovfii- 

 ariiis) which is not known to 

 have been found in this county* 

 I)rior to is."i,"), although it was /''ff- ■* 

 common about l'hiladcl])hia in Thomas Say's 

 time. It is more than twice as large as Fig. 

 4, of nearly the same form, of bronze-brown 

 color, and is particularly distinguished by 

 having a longitudinal row of blunt spines on 

 the middle of the thorax, that remotely re- 

 semble a ))ortion of a cog-wheel, or the part of 

 ii circidar above a plain surface. 



Several s\n'- 

 cies of "ground 

 l)eetle," of the 

 predaceous 

 families, have 

 been found 

 feeding on the 

 larva of the po- 

 tato beetle, 

 among which 

 are the "Fiery 

 ground beetle" 

 ' '' \ ( Calosoma ridi- 



(/«»(, Fig. ."i, a, the larva, and b, the imago), 

 a large lilack insect, with many copi)ery spot-s 

 on the wing covere; and at least three otlicr 

 common and well-known species; and lastly, 

 it is on record that the common gray "Hlister 

 beetle," which itself feeds upon the potato 

 toi>s, as a change from its vegetable diet, 

 manifests a redeeming trait by making nieat 

 of the Colorado l)eetle. 



If recent observations have demonstrated 

 that potato beetles will also feed on tomatoes, 

 egg-plants, thistles, iHRht-shade, lambs-quar- 

 ter, horse-nettle, henbane, jimpson-weed, 

 raspberry, currant, ground-cherry and several 

 other plants, when the potato is not aceewible, 

 it is some consolation to know that time is also 

 bringing to light more of its natural enemies. 

 15ut let not the farmers depend upon their 

 friendsalone, bid co-operate with Ihein ; and we 

 have written this paper solely witli a view in 

 .some, measure to acquaint 

 them with the length and 

 breadth of the "situation." 

 The following commmii- 

 cation from an intelligent 

 .source will iiractically illus- 

 trate the iH'nelits derived 

 from the aid of the "Spined 

 Soldier l{n'j;"(((, the jointed piercer aiidsucker; 

 and b, the bug itself, with tlie riglft wing 

 expanded.) See Fig. G. 



