Circular No. 99. 
 
 
 United States Department of Agriculture, 
 
 BUREAU Ol KNTOMOLOG 
 L. O. HOWARD. KntomolqgUt and Ch 
 
 THE M I w i r\ 
 
 Bj I II I 'ill I I I M'KN. fi 
 
 I \ I BOD1 i I i"\. 
 
 Nut-growing in tin- United States would in- a>i<m-ii u|*>re rtp*iiiai>l. 
 in d ust n were it not for the insects which inhabit t heTTTTieT-. render 
 them until for food. This is especially true of the chestnut and 
 
 chinquapin and to ;i lesser extent of | an, hickory, and hazel nuts; 
 
 while others, which include butternuts, walnuts, and almonds, suffer 
 little or no injury from this source. Considerable diminution in the 
 yield of 1 1 1 : i n \ forms of nuts is ; » I — « » caused by the inroads of insect 
 larvae in the growing husks. Examples of the first class are the chest- 
 nut " « orms "ur weevils; of the second, the husk- worms and walnut 
 curculio. The present paper will be restricted to a consideration of 
 
 the weevil-. 
 
 The chestnut crop suffers the greatest loss, and the chief depredators 
 are the grub like " worms " or larvse with which everyone i- too dis- 
 tressingly familiar. These larvae develop vi ith the nuts, so that those 
 which first attain maturity are read} to leave and enter the ground 
 nearly as soon as the nuts 
 are gathered ; others re- 
 main in the nuts some 
 weeks later; so it fre 
 quently h a p \> e n - that 
 when nni- are !>;ic U e il 
 for shipment in bags or 
 barrels, some nuts which 
 ueiv apparently sound 
 when shipped are found, <>n reaching their destination, with one or 
 more holes in their shells (fig. I), while the repulsive grubs crawl 
 about at the bottom of the receptacle. II "\\ to cope with these weevils 
 has long been a most vexatious problem. 
 
 I'm ( "ill- i \ i r Wi EVILS. 
 In comparatively recent years chestnut culture has assumed consid- 
 erable proportions, and has taken a new impetus since the extensive 
 introduction and development <>t" .la pane-r ami European varietie- 
 
 I 
 ma 
 
 lan " ii i anthoi - 
 
 itnxliirtion ami development ol .ia pane-r ami iMiropeati varietie- 
 Tiese are grafted on American seedling* or name -jo- L-. and thu 
 ianv valueless tree- on equally nnproinit-mu -mTiHv ronverte.II int 
 
 'Reprinted from Tearbook "f the Departmi JgHcaJtijre^for 1901, \>p. 
 
 299 310, I'ls. XX \ III 3 
 [Clr. :>o] 
 
 xxx. tezl Bga I i 
 
 US DEPOSITORY 
 
sources of profit. Were it not for the "worms." "borers/' and 
 "blights," chestnut growing might develop into a most lucrative in- 
 dustry in regions adapted to it. 
 
 Estimates of losses. — A fair estimate of the damage done annually 
 by weevils to chestnuts grown in the Tinted State> would probably 
 fall little short of ->."> per cent, while in some years the percentage 
 exceeds that figure, running as high as 40 or 50 per cent. Growers 
 in some localities report no damage, others place losses as low a- ."> 
 or 10 per cent, while instances are cited of whole crops being de- 
 stroyed. The amount of loss is dependent on locality, season, and 
 to a more limited extent on the variety of nuts grown. The greatest 
 damage is usually incurred in regions where chestnuts have grown 
 wild for many years, and the least where there are no wild chestnuts 
 or chinquapins and the nuts are grown only for market and are care- 
 fully gathered. The most extensive losses, judging from available 
 sources of information, appear to be in Massachusetts, Pennsylvania, 
 New Jersey. New York (in the vicinity of New York City). Delaware. 
 Maryland. Virginia, Tennessee, and North Carolina. 
 
 In Georgia. Spanish and Japanese varieties have been cultivated for 
 years without attack by weevils being noticed. In New Jersey. 50 per 
 cent of the same varieties have been ruined. A grower in Missouri 
 has reported no damage to 50 trees of an American variety: another 
 at South Haven. Mich., has reported no injury for a period of three 
 or four years to Japanese and Spanish chestnuts grown there, while 
 from 5 to '20 per cent of the crop of native nuts was annually de- 
 stroyed. The nearly complete destruction of the chestnut crop of 
 New Jersey for 1803 was reported. 
 
 The species oe chestnut weevils. — The species of weevils which 
 infest chestnuts are two in number— the larger chestnut weevil, Tiahi- 
 ninus proboscideus Fab., and the lesser chestnut weevil. B. rectus Say. 
 They have extremely long, slender beaks or snouts, nearly as fine as a 
 horsehair, and considerably longer than the body in the female. By 
 means of this long beak the female is able to penetrate the thickest burr 
 of the chestnut with its long spines and to cut out. with the minute and 
 sharp mandibles at the tip of her beak, a little hole for the deposition 
 of her eggs. These are inserted through the husk into the growing nut. 
 
 The two species resemble each other greatly in color and in .mark- 
 ings, the general color of both being golden yellow, ochraceous, or clay 
 yellow, frequently tinged with olive, and a little paler on the lower 
 surface. The disk of the thorax is a little darker, with a wide bright 
 band on each side, and the elytra, or wing-covers, are mottled with 
 rich light brown or dark brown markings of variable size and extent." 
 
 "Occasional individuals lack the darker markings, some being: paler, others darker, even 
 reddish. The ground color, as may lie seen in abraded specimens, is really black, and the 
 apparent color is due to scales very similar to those of butterflies and moths. 
 [Cir. 09] 
 
I ill l vin.l R CHESTNl 1 WEEVIL. 
 i liiiln ii in u i pruboacidcu* Pub > 
 
 The larger chestnut weevil (fig. 2) is considerably the larger and 
 more robust species. The female rostrum or beak, although proportion- 
 ately of about the same length 
 as in the lesser w ec\ il, ia per 
 ceptibly more prominent !»• 
 cause l«'-- curved, the cur\ at ure • 
 being toward the tip. Ii ia rv ^V ri 
 
 also more w idened at the base. 
 The body measures From < m*>- 
 third to nearly one-half of an 
 inch in length, and the beak 
 of the female is often five 
 eighths "I" an inch long. That 
 of the male i fig. ■_'. i ) ia nearly 
 as long as the elytra. The 
 
 IS small, RDOUl One-six-^o n>. largei chestnut weevil 
 
 , .. , | i ,- ■ 'i Female beetle; b, lame in ootllne from 
 
 (eenth Of an inch long, and <>l . andantenna of male 
 
 the Outline shown in figure ttmea natural atse (author's UlustraUon 
 
 ."..</. It is nearly white, partially translucent, and without sculpture. 
 
 The larva < fig. 3, a ) is 
 milk-white, robust, fully 
 three times BS Long as wide. 
 
 with the dorsal or upper 
 portion rounded and con- 
 vex. The entire surface is 
 very st rongly \\ rinkled 
 transversely, and there are 
 
 Kn. :i -Larger chestnut «■■ g \\-\\ \crv -hort hair- -cat- 
 
 a, Lai muli' papa; ■'. »•«* all enlarged (an- ' 
 
 tbar'ininitraUon tercd sparsely over the dit- 
 
 t'erent segments. The head i tin. 1 1 i- about one-fourth as wide as 
 
 the widest portion of the body. It i- provided with 
 
 shorl Inn strong mandibles, by means of which it gnaws 
 
 the kernel constituting it- food. The fully developed 
 
 larva in ordinary resting position measures nearly half 
 
 an inch. Although the larva has do true legs, it i- able 
 
 to crawl, -lowly and clumsily, it i- true, by mean- of 
 
 of the flattened lower surface, locomotion being aided 
 
 l'\ transverse wrinkle-. 
 
 The pupa i- of a clearer whitish color than the larva, 
 and -how- the principal external organs of the body of nioatmtlon • 
 the future beetle, all. except the beak, folded tightly t<> the l»od\ 
 The female pupa i- illustrated in figure 3, '-. . 
 
 [Ctr. '.'•.'] 
 
 • 'i in ii* 
 
 Unch en- 
 
This species, like the other weevils under consideration, is native to 
 America and is known from Rhode Island to Virginia, the District of 
 Columbia, southern Ohio, and Tennessee, and westward to Kansas. 
 The geographical distribution of this and the other nut weevils has as 
 yet not been carefully studied, hut in all probability it is considerably 
 more extensive than above stated. 
 
 In some regions this species is quite generally known as the chin- 
 quapin weevil, hut the investigations conducted during L904 indicate 
 that, although it hreeds in chinquapins and more commonly in chest- 
 nuts, it occurs in greater abundance in the larger imported nuts. 
 
 THE LESSER CHESTNUT WEEVIL. 
 
 i Balaninus /(tin* Saj . i 
 
 The lesser chestnut weevil (fig. 5) has the scape of the antenna 
 longer than in the preceding species and the first joint longer than 
 
 the second." The average 
 length of the body is about one- 
 fourth of an inch, hut the size 
 varies, as in all of these insects. 
 The distribution of this 
 specie- extends from Canada 
 and Massachusetts to North 
 Carolina. Tennessee, and Ohio, 
 ami probably farther west- 
 ward. The writer ha- seen sets 
 of specimens labeled "Arizona." 
 
 Although in some localities the 
 Pig. 5. — Lesser chestnut weevil i Balaninui rectus) 1 ■ ■ i_ 
 
 adult: a, Female, dorsal view; b, female, lateral liU ^' 1 ' S P eCleS lS lllll( ; h ln ° n ' U1 
 view; c, head of male. Much enlarged (author's evidence, taken all ill all. the 
 illustration). i ■. • tl 
 
 lesser weevil is the more com- 
 mon and is probably even more widely disseminated. 
 
 The egg has not come under observation, but is undoubtedly very 
 similar to that of the preceding, being proportionately smaller, which 
 is true of the remaining stages. 
 
 The larva is only a third of an inch long and its length is about 
 three times its width. The body is milk-white and the head light 
 brownish yellow, while the i-mark has a short lateral branch each 
 side. 
 
 The pupa differs from that of the larger species by size and by 
 characters shown in figure 6, which illustrates the male. 
 
 " In the larger species the first joint (omitting the scape) is shorter than the 
 second. In the female rectus the rostrum is strongly curved, the thorax is 
 longer than wide, and the elytra are strongly acuminate apically. The tooth 
 with which the thighs are armed is small, with the entering angle rounded. 
 [Cir. 99] 
 
1 I II MOTOR 1 ' l BOTH 8P] i 1 1 -. 
 
 rhe life history of our two chestnut weevils is so similar as to be 
 practically the Bame for both species. There are, however, minor 
 differences. These, as well as r< lated mil and acorn weei ils, hibernate 
 exclusively in the larval condition and in the soil. Both make their 
 
 Rrsl appearance ai about the same time with the first bio g of 
 
 chestnuts but this period may varj from late in June to July, 
 
 according to locality and season, or, more properly speaking, the 
 
 mean temperature. At this time the beetles are found rarely and 
 
 scatteringly, and as oviposition has not been observed then ii is 
 
 doubtful whether it begins until considerably later. What function 
 
 these early arrivals fulfill is problematical. The beetles increase in 
 
 number as the nuts approach maturity, or until about the middle of 
 
 September or a little time before the nuts are first marketed. Then 
 
 they max be seen in greater abundance, several pairs, frequently of both 
 
 species, often occurring on a single bunch 
 
 of burrs | fig. 8). A- it requires about two 
 
 weeks for the egg to develop, it is not prob 
 
 able that the} are laid much earlier than 
 
 when the nut begins to form. Prom exam 
 
 ination of many burrs gathered in the fall 
 
 of L904 by Mr. V. C. Pratt, of the Bureau 
 
 of Entomology, \\ ho \ isited some of the 
 
 principal chestnut groves of Pennsylvania K »r chestnui weevil 
 
 and Virginia at the urgent r ,est of gro* 
 
 ers in those States, it is deduced that the riKl " En ' ai... r -. 
 
 first eggs deposited are laid (seldom and 1 ""- tr,,l "•" '• 
 very sparingly | in the soft, woolly material surrounding the forming 
 nut; but later they are inserted in the knurl jusl under the inner 
 skin, and occasionally they are deposited somewhat more deeply. In 
 no case has the egg I n found in the outer husk. 
 
 Eggs are laid singly, bul many are placed iii a single nut, as high as 
 l" or more (of the -mailer weevil i in imported nuts, and as many as 
 '•» in native nut-. The larva; when hatched feed on the tissue of the 
 growing kernels, enlarging with their own growth the cells thus made. 
 W hen. as i- usual, several larvae inhabit the same nut, the interior is 
 more or less completely hollowed out, and large ma—- of excremenl 
 are left behind i fig. 9). 
 
 I'».\ the en, | of September or the first weeh of October the beetles dis- 
 appear. At about the same time, when the nuts first fall, the larva? be- 
 gin to mature and issue from round orifices which they gnaw through 
 the shell and which vary in diameter from one-i \teent h of an inch, in 
 the case of the -mallei- species, to one-eighth of an inch in the larger 
 (see fig. 7 1. By the size of these hole- alone it can be readily deter- 
 mined which species is the dominant one m any given locality Rarelv 
 
 [Cir 
 
Fig. 7. — Chinquapins, showing injury l>> les- 
 ser chestnut weevil at left; of larger weevil 
 nl right. Enlarged (original). 
 
 larvae bore through the burr. (>n leaving the nuts they burrow into 
 the earth to depths varying from -2 to about 8 inches, according to the 
 hardness of the soil. If confined in soft earth or sand they penetrate 
 -till deeper. The larval period probably lasts from three to live weeks 
 in the nuts, and about ten months m the earth, pupation taking place 
 
 within three weeks of the issuance 
 of the beetle, the latter remaining 
 several days in the earth before 
 appearing above ground. 
 
 The beetles do not fly readily, but 
 cling tightly to their resting place 
 or drop when disturbed: yet, as 
 their bodies are not heavy and their 
 winirs strong, they are obviously 
 able to cover considerable distances, 
 especially with the wind. Ordina- 
 rily, however, they are sluggish, 
 like most other weevils, and probably do not go far from the vicinity 
 of the trees which have sheltered them as larvae, although they 
 undoubtedly migrate when food is scarce. 
 
 NATURAL ENEMIES. 
 
 A natural enemy of the nut weevils is known, a small four-winged 
 wasplike fly, the braconid parasite Urosigalphus armatus Ashm.. 
 which develops in the body of the larva. * : 
 
 METHODS OF CONTROL. 
 
 The most practical remedy for nut weevils that can be suggested is 
 the early destruction of the " worms" in the nuts by means of bisul- 
 phid of carbon and the observance of clean orchard management and 
 other cultural methods. It may be well to preface the discussion of 
 these methods with a statement of the uselessness against nut weevils 
 of ordinary measures employed in the control of similar insects. 
 
 Unsatisfactory Methods. 
 
 Stomach poisons. — The peculiar structure, in the nut weevils, of 
 the mouth-parts (minute mandibles placed at the end of a beak nearly 
 as fine as horsehair and as long or longer than the body) is almost 
 sufficient proof in itself that these insects do not feed on leaves, but 
 depend for sustenance on the substance of the growing nuts. The 
 beetles first appearing feed on the undeveloped, very young nuts and 
 the juices within the husk. There is. therefore, no seeming possibility 
 of reaching them with a spray of Paris green or other stomach poison. 
 
 "Two other insects are associated with the weevils and are probably also 
 their enemies, n proctotrypid parasite. Trichasis mflpes Ashm., ami a predatory 
 reduviid bug, Acholla multispmo&a Dec. 
 [Cir. 99] 
 
FN 
 
 B i.;ir:'T chestanl \% • • • ■ \ i I "ii chinquapin barn Twice n:itm-:il b1k (original). 
 [Or. !>!>1 
 
PIG. 9. — Imported nuts, showing different forms of injury by nut weevils. 1 — Parry's 
 Giant nut, showing exit hole of Balaninus probosddeus ; 2 — Same of /;. rectus: :> — 
 Interior of Paragon nut, showing larva' of H rectus in situ; 4 — Same, showing work of 
 one individual of /( proboscideus ; 6 — Reverse side of figure 2. showing sears made by 
 puncture of female n rectus in ovipositing: 6 — Reverse of figure l. with puncture of 
 /{. proooscidetw. All natural size (original). 
 [Cir. 99] 
 
particularly as we are unable to place the insecticide where they 
 « until iii enough to kill i hem. 
 
 Trap crops. The cultivation '>f special varieties of nut- with a 
 view to securing immunity from attack or as ;i means of luring the 
 insects from the main crop does not offer any degree of promise. The 
 Paragon, Cooper, and Ridgele} varieties, according t" Mr. <■ II 
 Powell, of the Bureau of Plant Industry, suffer greater 1"-- from 
 weevil attack than Japanese varieties. Chinquapins are favored l>\ 
 the smaller weevil and suffer far more damage, as a rule, than wild 
 chestnuts. Ii is possible thai the planting of the varieties specified, 
 or, better, of chinquapins, at intervals around, as also through, 
 orchards of the leasl affected varieties might lessen the loss to the 
 main crop. If a variety could be produced which would mature fruit 
 before the advent <>t' the beetles in greatest numbers, tin- would 
 partially solve the problem, particularly as the earliest nuts bring 
 the highest prices. The nuts gathered toward the end of the season 
 are comparatively uninjured, l>m by this time the market value is 
 considerably lower. 
 
 (uni M i poisons. Scarcely more can be expected from the use of 
 contact poisons, such a- kerosene emulsion, since in view of the long 
 period spent by these weevils in the adult stage ( from June and July 
 to September or October) such frequent application would be ui 
 Bary that the expense would destroy the profit. 
 
 Jarring mr nusES, as practiced againsl the plum curculio, is for 
 the same and other reasons equally impracticable, save, perhaps, on 
 young tree- grown in a -mall way. 
 
 I'm w \ 1 1 1: it — i - m i mi -i \ i H in. Having doubts of the efficacy of 
 this old-fashioned test of the difference between ■•wormy" and 
 healthy nut-, an experiment was made by the writer witli native 
 chestnuts obtained from a street vender. To begin, I" per cent were 
 obviously " wormy." ami only 60 per cent apparently sound. 
 
 Results of water tests icith nai tnuts. 
 
 i iiirti rose • 
 
 
 Unlnfwted 
 
 I Ing minute marks only: good 
 
 Vrr cn< . 
 
 ■ 
 
 10 
 80 
 
 In norfivt condition 
 Slightly injure! 
 
 Completely iiium with grata 
 
 Per cent . 
 
 10 
 
 30 
 20 
 
 lining full irmu n grabs 
 linlnc Immature grata 
 
 
 A- will be -ecu from this experiment, noticeably wormy nut-, as 
 evidenced by loss of weight and the exit holes of the "worms," 
 naturally rise when placed in water. l>ut the remaining nut- may or 
 may not he infested, and hence require further test than whether 
 they will -ink or float, 
 [dr. '.''.'l 
 
10 
 
 I >iiu.< t Remedies. 
 
 Bistjlphid of carbon. — The value of bisulphid of carbon as a fumi- 
 gant for chestnuts infested by weevils is now fully established. 
 Although at first thought it would seem difficult for the gas to pene- 
 trate through shells so firm and compact and kill the larvae, neverthe- 
 less a prominent grower in Pennsylvania successfully uses the bisul- 
 phid, applying it when the nuts are first harvested. The dead weevil 
 larva' are at this time so small that the average person would never 
 detect their presence, while if they were permitted to develop they 
 would soon destroy the nut for food. Bisulphid of carbon has been 
 used on the largest chestnuts grown in this country, and. since a score 
 or two of larva' find shelter in a single nut. one can appreciate the 
 desirability of prompt fumigation. The grower mentioned uses 
 bisulphid of carbon at the rate of 1 ounce to a bushel of Paragon nuts 
 placed in a kerosene barrel of about 50 gallons capacity and covered 
 by sacking. After an exposure of about sixteen hours the nuts are 
 removed, the larva' being then practically all destroyed. Several 
 hundred pounds were treated in 1901 in this manner with perfectly 
 satisfactory results. To verify reported results. Mr. Pratt was 
 detailed to visit the infested orchard and witness the process. This 
 method could be employed at less expense by using tightly fitting 
 covers, the effectiveness of the fumigation being in exact proportion 
 to the tightness of the receptacle and the length of exposure to the 
 fumes. Therefore, a longer exposure of one or two days, with per- 
 haps one-half ounce of bisulphid. should accomplish the same purpose. 
 
 Scaldino and DRYING. — Some growers make a practice of plunging 
 the nuts as gathered into boiling water just long enough to kill the 
 contained insects and yet not injure the nuts for sale, after which 
 they are dried before being marketed. This may be profitably accom- 
 plished by using a large sieve, which is filled with nuts, dipped in the 
 water, and removed in about five minutes. The late W. P. Corsa 
 used a washtub, in which was placed a bushel or so of nuts, pouring 
 in enough boiling water to come an inch or two above the nuts. 
 Then, by stirring vigorously with a stick, the bulk of the weevilly 
 nuts would come to the surface in the same manner as do peas and 
 beans affected by weevils. The infested nuts are skimmed off and 
 destroyed, or they may with profit and safety be fed to hogs, pro- 
 vided the animals do not have a too exclusive diet of this form of 
 food. Salt water, it is claimed, is preferable for scalding, the brine 
 serving to keep the shell soft and pliable and rendering the kernels 
 more palatable than when not thus treated. 
 
 Different methods are employed in drying. A good way is to place 
 the nuts in the sun and agitate them occasionally by stirring or 
 
 " .Note the writer's observations on this head on p. '.». 
 [Cir. 99] 
 
11 
 
 shaking in a bag until thoroughly dry, because it moisture remains 
 unevaporated it is apt t°> form mildew when the nuts are prematurely 
 packed for shipment. 
 
 \ut- for planting should i><>i !>«• scalded, and care should be taken 
 iidi to cook the kernels of nuts intended for sale. Sum.- growi 
 claim thai the hot water treatment is objectionable because the nul 
 shells lose a certain degree "f polish, rendering them less desirable 
 for market. 
 
 Heat. Infested nuts can !><• subjected t<» a temperature of be- 
 tween L25 F. and 150 I", without injuring them for food or for 
 -ci'd. Mini tin- will effecl the destruction of the larva; within. Some 
 growers of chestnuts destroy the weevils by kiln-drying. 
 
 Cold storage. Cold storage has been employed and is successful 
 in arresting the development of the larva?. The appearance of the 
 nuts is scarcely different from that of those not so stored, but nuts 
 thus treated and submitted to the writer after becoming dry were 
 deficient in flavor, having an acrid and moldy taste. 
 
 \ crude form of cold storage has been successfully followed by a 
 Virginia grower. It consists in placing nuts in the earth under the 
 -hade afforded by his house, where the soil temperature, after the 
 nuts are gathered, doe- not exceed "> 11 . Since most insects are ina< 
 live below 51 thi- has the effecl of restraining their development, 
 causing the eggs or minute larva; to die. 
 
 Phi \ i \ i m i -. 
 
 Choice of ux IlTion fob mi orchard. The -election for the 
 planting or grafting of chestnuts of a locality with reference to the 
 chance- of immunity from injury by nut weevils is a matter of great 
 importance. For this reason it i- most undesirable to plant in the 
 immediate vicinity of woodland abounding in wild chestnut and chin 
 quapin, since these trees furnish natural breeding places for the in- 
 sects, and are, therefore, a constanl menace to successful chestnut 
 culture. Too frequently growers suffer losses from weevils because 
 they neglect to gather the wild chestnuts or chinquapins in the im- 
 mediate vicinity of their cultivated groves. Another phase of had 
 management which i- frequently practiced is the grafting of culti- 
 vated varieties on native chestnuts growing in rocky and uneven soil, 
 often on hillsides, as shown in figure 11. In such place- it i- impos 
 sible to har\e-t a complete crop. and. what i- of equal importance, to 
 gather the remnant-. Hence, to secure these results, it is impera- 
 tive to plant or graft trees on smooth ground (fig. 12), tir-t for the 
 sake of economy, and second to permit the collection of all of the 
 nuts, leaving none for the propagation of weevil-. It is also neces 
 sary to keep the soil clean of herbage, as shown at the left of fig 
 ure L2 — not overgrown with brush, a- illustrated at the right. 
 
 [Clr !)!»] 
 
12 
 
 Careful harvesting. — It is always advisable to gather the entire 
 crop, leaving none on the ground, and cither place the nuts in ti<rht 
 receptacles or fumigate with bisulphid of carbon before marketing. 
 The grubs crawl out soon after the nuts have been gathered, and as 
 
 they require considerable moisture they will die ii' confined in closed 
 barrels or boxes. The trouble is that enough nuts are usually left in 
 orchards or in adjoining wood or forest land to serve for the propaga- 
 tion of the insects the following year. In order to make the method 
 of treatment here described thorough, it will be necessary to secure the 
 cooperation of neighboring landowners who grow chestnuts for mar- 
 ket and of all who own woodland containing chestnut and chinquapin. 
 
 The collection of remnants can be made by children or the unem- 
 ployed. It is also profitable to allow hogs the run of the orchards to 
 destroy what nuts remain after the crop has been harvested. In the 
 mountainous sections of Virginia and Pennsylvania it is a common 
 practice to fatten swine on the unpicked fallen nuts. Hogs fatten on 
 nuts and acorns as well as on corn, and without expense to the grower. 
 
 Cooperation. — The results of the observance of clean farming on 
 the lines that have been indicated may not at once be apparent, but in 
 course of time, if this work is systematically carried out by all grow- 
 ers over a considerable territory, infestation will be very materially 
 decreased. An important point is to ascertain how far the insects 
 fly. Their structure indicates that they are strong fliers and capable, 
 with favoring winds, of migrating considerable distances; but under 
 ordinary circumstances they probably do not fly many miles at a 
 time or in a given year. 
 
 The Pecan Weevil. 
 (Balaninus oaryx Horn.) 
 With the increase of pecan culture in our southern States frequent 
 inquiry is made in regard to the cause of the holes in the nuts 
 
 (fig. 10). and during 
 IDO.i and 1904 there 
 were reports of great 
 injury of this nature, 
 more particularly to 
 pecans grown in Texas, 
 where considerable loss 
 was reported, and in 
 Georgia, where in one 
 locality 7."> per cent of 
 the crop was a failure. 
 A shortage has also 
 been reported in Mis- 
 sissippi. The insect involved in these cases is the pecan or hickory- 
 nut weevil, a pest which is evidently destined to become one of the 
 [Cir. !)'.)] 
 
 Fig. in. 
 
 -Pecan nuts showing exit hole of pecan weevil larva-. 
 One-third enlarged (author's illustration!. 
 
i:: 
 
 Pia 1 I I 'aragon cbekl nut orcl 
 
 bard management, 
 
 Paragon chestnut growing on plan.' surface, where dean methods of cultivation 
 
 i an be practiced. 
 I fir. DO] 
 
14 
 
 principal drawbacks to the cultivation of the pecan. Indeed, in many 
 parts of the South it already divides that distinction with the husk- 
 wonu. so that it has been truthfully said that what the husk-worm 
 leaves the weevil destroys. 
 
 The beetle (fig. 13) is about the same size as the larger chestnut 
 weevil, from which it may he distinguished by its much duller color 
 and by the relative lengths of the first and second antenna] joints, the 
 first joint being longer than the second in the pecan-infesting specie-. 
 The larva differs from that of proboscideua in heing decidedly yel- 
 low, having the head bright 
 red and wider than long. Its 
 cervical plate also is darker. 
 The pupa is similar to that of 
 the larger chestnut weevil. 
 
 The distribution extends 
 from New York to the (iiilf. 
 and westward at least to Iowa. 
 The life history of this wee- 
 vil, as it occurs in the pecan 
 in the South, is. so far as can 
 be gathered from reports from 
 Georgia and Texas and from 
 laboratory experiments, very 
 similar to that of the chestnut 
 weevils. According to the ob- 
 servations of Mr. H. A. Halbert. at Coleman. Tex., the female begins 
 to deposit her eggs in August while the pecan is still immature, and 
 the larva usually escapes from the nuts in the latter part of Septem- 
 ber and in October; but most of them do not issue until the husks 
 open, allowing the nuts to fall. In Georgia they have been found in 
 the nuts as late as the middle of January. 
 
 REMEDIES. 
 
 The same care in the selection of the site for a pecan orchard is 
 advised as in the case of chestnut culture, with this difference, that the 
 grower should avoid planting in the vicinity of wild pecan and hick- 
 ory of whatever kind. The entire crop, also, should he harvested or 
 hogs should be turned in to devour what nuts are left. At Thomas- 
 ville, Ga.. Mi-. YVilmon Newell observed in L904 that where swine ami 
 chickens had had access to a pecan grove, the ground was well rooted 
 and scratched up and there was less Loss from weevils than in the pre- 
 
 " Tlie ground color is uniform dark In-own. nearly black, and the scaly covering 
 i which characterizes the chestnut weevils) in this species is hair-like on the 
 thorax, line and somewhat sparse on the wing-covers, and much duller, with 
 little or no mottling. Moreover, the beak of the female is. comparatively, a little 
 shorter, although of about the same curvature, and is less widened at the base. 
 [Cir. !':>] 
 
 Fig. 13. — Pecan weevil (Balaninus caryse): a, Female. 
 dorsal view; b, same, lateral view, in outline; 
 c, head with rostrum and antenna of male. About 
 two and one-half times natural size uiuthor's 
 illustration). 
 
15 
 
 vious year. Evidently both hog and poultry devour the larva? in the 
 ground. 
 
 At the time that bisulphid of carbon was first suggested as a remedy 
 for chestnut ''worms" if was feared thai the firm and compact shell 
 would hardly permit the gas to penetrate and kill the contained larva). 
 Experience, however, has shown that this remedy ia successful in the 
 case of chestnuts, and it is not impossible tliat it might be adapted to 
 pecans, using ;i larger amount of the chemical and a longer exposure 
 in a perfectly tighl receptacle. We can as yet scarcely advise this 
 method on a large scale, but it should certainly be tried experimentally. 
 
 Tin 1 1 \/i i.m i W ii \ ii.. 
 (Balaninut obtusua Blanch.) 
 Hazelnuts or filberts are injured in much the -nine manner as are 
 chest 11 in- and pecans and by ;i similar weevil. Injury was recognized 
 :i- early as 1841, !>ut was attributed to 
 other species than that under considers 
 t ion. Owing to the comparatively slight 
 importance of the hazel as a nut tree in 
 this country, few notices of losses from 
 weevil attack have been recorded. The 
 
 weevil which ailed- the nut was not 
 differentiated from others of its kind 
 until 1884. In 1891 ii was reported as 
 badly damaging hazelnuts in Iowa 
 
 The beetle ( fig. 1 1 ) differs from others 
 which attack edible nuts, exclusive of 
 acorns, by its shorter, more robust form 
 and shorter beak.' It is about one- 
 fourth of an inch in length, and the 
 
 beak doe- nol exceed half the length of the body. The vestiture 
 raries from gray to ochreous', and the elytra are moderately mottled. 
 
 This species occur- from Massachusetts and New Hampshire west- 
 ward to Minnesota and Texas. Injury has been noted in Massachu- 
 setts, New York. Indiana. Iowa, and Minnesota. 
 
 Of the life history little has been recorded beyond the fact thai the 
 
 " worm " issues from the -ide of the nut. and that paired adult- have 
 been found on hazelnut- in duly. 
 
 1:1 mi mi -. 
 Since hazel- are not cultivated in this country to any extent, no rem- 
 edy need be employed other than gathering entire crops and destroy- 
 ing isolated bushes where it i- unprofitable to gather the nut-. It 
 
 would he quite possible, owing to the -mall size of the hazel plant, to 
 control this species by jarring, a- for the plum curculio. 
 
 ■"Tin- appendices of tin' claws are broadlj rectangular, and the femora or thlgl 
 arnuMl with large teeth The scape at the antenna in ti\.- female i- long. 
 
 Fig, i i — Haaalnnl tfaninui 
 
 aofwiM . adult: a, Female, •icr-jii 
 vi.u , ;. head from side ■ bead of 
 male from side, Enlarged (original i. 
 
 I fir '.>!>] 
 
 o 
 
UNIVERSITY OF FLORIDA 
 
 
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