mm ■i' 4 '.^^^^1 1 Ij IP ^?BRIM^. -^7> ""^^ON L\^^ Class .^.^.*^.-.X2:>- Number JV.^.^.... Volume . Source... .<^^r*^. X ^..va-^A- Accession No. \5"A"^S Bulletin 128. January, 1907. NEW HAMPSHIRE COLLEGE Agricultural Experiment Station IN COOPERATION WITH THE State Board of Agriculture AND THE Bureau of Entomology, U. S. Department of Agriculture THE BROWN-TAIL MOTH By E. Dwight Sanderson state Nursery Inspector and Entomologistof the Station AND 1*^. ^ ♦'i%v r ■^-jiTji , THE GIPSY MOTH By Dr. L. 0. Howard Chief of Bureau of Entomology, United States Department of Agriculture IN NEW HAMPSHIRE IN 1906 NEW HAMPSHIRE COLLEGE OF AGRICULTURE AND THE MECHANIC ARTS DURHAM L. ! V M 1-rt.W 5farJ( .1 .>5i^^^ C yj. rteajte»* I /_ < Bt rl l^ \^ ^ — Ti'' i jf ^t7 .^""'^'^'is^' i~. /-!^ , L^ "'>A-- ' ■> *^ r- -^•- J nt»0''«*w' - .>'\_.r.::g l^andu/icJl 1^^, .^^ >-^ Msi ■■■> /' SaMbo**«/oW \T-jr \ , 1 •'<'<•'•/ 1106 S^t^ji W03 Figure 1. Map showing the gradual spread and distribution of the Brown- Tail Moth in New Hampshire. Dotted area infested in 1906. Heavj- lines are outer boundaries of areas infested in years indicated at margin. Dash lines represent approximate boundaries not personallj^ investigated, based on points infested north of them. Black circles show points examined in January, 1906, and found uninfested. Black squares show points examined in Decem- ber, 1906, and found uninfested. Towns shaded with horizontal lines found infested in December, 1906, and those underlined within 1906 boundary are undoubtedly infested, though not personally' examined. THE BROWN-TAIL MOTH IN NEW HAMPSHIRE. Spread and Present Distribution. During July, 1906, the brown-tail moth continued to spread to the northwest into Grafton County, and north into Carroll County, but failed to spread westward into Cheshire County. Examinations made by an inspector of this station in November and December, 1906, show it to have spread over the area indicated in figure 1 in 1906. In those towns shaded the winter webs were found. The other towns within the boundary line connecting these towns were not examined but are undoubtedly infested. The following is a list of these towns, with those in which the webs were found marked with an asterisk.^ Grafton County. *Moultonborough. Alexandria. *Tuftonborough. Bridgewater. * Center Harbor. Bristol. Merrimack County. *^^^fton. Andover. ^^^t^^- ^Bradford. Hebron. ^Danbury. Orange. jj-^ ^Plymouth. Newbury, mumney. ^^^ London. Sullivan County. Salisbury. Springfield. Sutton. Warner, Carroll County. Webster. * Sandwich. Wilmot. 1 For the previous distribution and spread of the brown-tail moth in New Hampshire with a full account of its life history, remedies, etc., see Bulletin 122 of this Station. 212 THE BROWN-TAIL MOTH IN NEW HAMPSHIRE. In all twenty-five towns were probably newly infested during the summer or the area infested in New Hampshire increased about twenty per cent. On the north the moths crossed Lake Winnepesaukee and are not diffi- cult to find along' its northern shore and in southern Sand- wich. The moths came into Meredith and Plymouth in large flights in mid-July. Webs were not found in Camp- ton and it seems probable that the mountains with a scarcity of fruit and deciduous trees for food will make further spread much slower. Eight towns were examined in Cheshire County and Claremont and Newport in Sullivan County, but no webs were found. Present Condition in Towns Previously Infested. Throughout the coast towns where the moth has been longest and is therefore most abundant the heavy rains of May and June furnished ideal conditions for the growth of a fungus disease which destroyed thousands of the cater- pillars. This disease was not so noticeable ten or fifteen miles back from the coast, and will probably be equally effective only under similar weather conditions, which are abnormal. During January, 1906, there was a period of unusually warm weather, which it was asserted by the daity papers, would cause the young caterpillars to emerge from their winter webs. We were unable to find any which did so emerge and experiments conducted by us in subjecting win- ter webs to a greenhouse temperature and thus securing their emergence show that it would require a much longer period of such weather to cause the caterpillars to emerge even much later in the spring. In general the winter webs are very much more abundant over the area infested in 1905 than they were a year ago. For even where the webs were almost entirelv removed from fruit and shade trees in the winter of 1905 and 1906, the moths flew in July, 1906, from to^vns which had failed to THE BROWN-TAIL MOTH IN NEW HAMPSHIRE. 213 combat them, with the result that many towns which did good work in cleaning their trees of the webs a year ago must now do a larger amount of work on account of the neg- lect of neighboring towns. Work Done hy the Towns in 1905-'06. In general there was but little complaint from annoyance by the brown-tail caterpillars in the early summer. This was due to the excellent work done by most of the towns and cities in destroying the winter webs. To determine just what had been done to combat the pest by the cities and towns of the state a circular letter was sent to the mayors and selectmen, from practically all of whom replies have been received, asking the following questions : (1) What sum was appropriated for fighting the brown- tail moth in your town in 1906 ? (2) How was this to be spent? (3) What sum has been expended ? (4) Were the trees thoroughly cleaned of winter nests? (5) Have the moths appeared during mid- July in larger numbers than in previous years, if so to what extent ? (6) Would you favor state legislation requiring prop- •ertv owners to remove the winter nests of the brown-tail moths from their trees, providing the cost of the work would not exceed one half of one per cent, the taxable valuation •of the property and requiring the towns to see that this is -done ? This is the arrangement under which Massachusetts is now working and securing good results. The replies of these towns which made any appropriation are summarized in the following" table : 214 THE BROWX-TAIL MOTH IN NEW HAMPSHIRE. Town. Appropria- tion. Spent, 1905-'06. How used. Amherst ic. per nest Barnstead Bedford Candia Chester Chichester Concord Contoocoob Deerfield Durham East Kingston Epping Epsom Exeter Farmington Gilford Hampstead Hampton Hampton Falls Hollis Hudson Laconia Lee Litchtiold Loudon Manchester Mason Milford Mont Vernon Nashua New Boston New Durham Newington Newmarket Newton North Hampton Northwood Narrows. Penacook Raymond Reed's Ferry Rochester Rollinsford Somersworth South Hampton Tilton Windham Wolfeborough $500.00 Ic. per nest 100.00 100.00 100.00 300.00 200.00 300.00 50.00 150.00 200.00 50.00 100.00 50.00 200.00 500.00 100.00 100.00 50.00 150.00 75.00 100.00 200.00 $300.00 140.00 312.75 65.00 25.00 30 00 286.68 300.00 273.47 86.10 54.23 50.00 20.00 488.58 14.67 40.00 50.00 50.00 12.00 116.25 110.00 50.00 50.00 35.06 ? 38.52 75.00 38.66 500.00 7.00 10.31 10.00 150.00 35.00 100.00 50.00 23.54 75.00 280.68 77.50 40.00 50.00 40.00 100.00 100.00 $4,711.00 1 cent bounty. 2^ cents bounty. 1 cent bounty. Roadsides. Roadsides; abandoned farms. 1 cent bounty. Street trees." 3 cents bounty. 1 cent bounty. I cent bount\'. ^ cent bounty. 5 cent bounty. i cent bounty. Ba' selectmen. g cent bounty. 5 cents bounty. By selectmen. Road surveyors. By selectmen. h cent bounty. Contractor. Bounty. I cent'bounty. 1^ cents bounty. Street and park commission. 3 cents bounty. Hired men. k cent bounty. Park commission. \ cent bounty. 1 cent bounty. By selectmen. \ cent bounty. 9 § cent bounty. 9 5 cent bounty. 1 cent bounty. Parks and city trees. ^_ cent bounty Hired men. ^ cent bounty. The figures are somewhat misleading as the appropri- ations given are those made in March, 1906, while the amount spent represents that expended in 3 905 and the spring of 1906. In addition to the $4,711 spent by forty-seven towns re- ported, about $1,000 is known to have been used in cities and towns which have failed to report. So that probably nearly $6,000 Avas expended by cities and towns in New Hampshire in 1905- '06. THE BROWN-TAIL MOTH IN NEW HAMPSHIRE. 215 The following towns took no official action for the control of the pest, leaving it to property owners : Allenstown. Antrim. Atkinson. Auburn. Barrington. Belmont. Bennington. Bow. Brentwood. Brookfield. Brookline. Canterbury. Danville. Derry. Dunbar ton. Francestow^n. Fremont. Gilmanton. Goffstown. Greenfield. Hancock. Henniker. Hillsborough Bridge. Holderness. Hooksett. Kingston. Londonderry. ]Middleton. Milton. Northfield. North Weare. Nottingham. Pelham. Pembroke. Plaistow. Portsmouth. Rye. Salem. Sandown. Sanbornville, Seabrook. South Lyndeborough. Strafford Centre. Wilton. Hill. Summarizing the replies to the other questions, twenty- one report the moths more numerous in 1906, and thirteen state them to be less numerous, the majority failing to report. The selectmen of fifty-six towns reply in favor of state legislation, while only eight are in any way opposed to it. This shows most conclusively that although the work done by half of the tow^ns was w^ell done and most commendable, that unless all tow^ns assist in the fight it will be difficult to control the pest, and the cost of control will increase unduh^ Furthermore the method of paying bounties for the nests is hardly satisfactory. They are usually gathered 216 THE BROWN-TAIL MOTH IN NEW HAMPSHIRE. wherever found most abundant and are left where it is difficult and not worth the bounty to secure them. Is it not the duty of every property owner to clean his trees of this pest within a reasonable cost, and is there any reason why he should be paid for so doing? The large majority of re- plies from selectmen from all parts of the infested area show that public sentiment is strongly in favor of state legislation which will ensure the control of the pest in the best possible manner, making its control obligatory on every property owner and aiding the towns in their fight with an appropriation from the state. Fig. 2.— Apple trees on Water Street, Somersworth, N. H., defoliated by brown-tail moth caterpillars in June, 1906. the brown-tail moth in new hampshire. 217 Remedies. Destroying the Winter Webs. Cutting' off and burning' the winter webs (as described in Bulletin 122) is by far the most practical means of con- trolling the pest. The efficiency of their destruction was ^well shown in the City of Somersworth during the past sum- mer. The city and private property owners had done most excellent work the previous winter in destroying the webs, but in one or two cases the ignorance or obturacy of the property owner prevented the destruction of the webs by the city employes. In one small yard with scarcely a dozen fruit trees where the webs were not destroyed the caterpil- lars appeared in such numbers that every apple tree was absolutely defoliated (see figure 2) and were gathered by the peck at the bases of the trees. Thorough spraying of the trees with arsenicals and spraying the caterpillars which had crawled on neighboring fences and houses with pure kerosene, destroyed most of them. But the expense was ten fold what it would have been to have pruned off the webs in winter, and enough caterpillars escaped destruction to reinfest the whole community. In another case a limb of a large apple tree (Fig. 3, a) overhung a neighbor's yard in such a way that it was difficult to remove the nests with- out entering the adjoining property. Permission to do so was refused. As a result this branch and another tree (Fig. 3, c) on the untreated property was defoliated, while the rest of the tree (Fig. S, b), from which the nests had been removed, bore its normal foliage unmolested. Spraying. Frequently we are asked whether the caterpillars cannot be controlled by spraying. Spraying is effective if done early in May while the caterpillars are still young, but it is so much more expensive than to destroy the winter webs that it is rarely to be advised as the principle means of con- trol of the brown-tail moth. When the eggs hatch in early r— t o o d c >> >< ^ o d e '5 +- c. a it. *- a u © 0/ A 'be x: -tj c -*-> e *« c c »-* ® o ti (-^ > o ? to 3 'O o as ja a 1-H a cT 1— < e3 a jr 3 D d ^-3 J3 ■1^ d ffi a >» • o "5 !z; _o •■ '■3 A F^ o o « > u 02 a ,— ^M ® 5 01 ^i* a s +j '5 o o c CO a d Oi « 0) 4-2 ® cta •i-i a C r- •T^ -^ ^ r. w w r" 1. ;u G 3 .— O © •^^ x: rt ■? •*^ ^ ■i-2 ® r>^ 1 0 ^ c £ ^ )— 4 ■4^ ^ c3 35 •FN w ^ A ^ O 5 ^ ® -i-> ^^ r** > rt O ^ 0 •*-' rt O ■G K a ® O 0) O '^ 0) h o -a ® c. "C 82 ^ C^ d S3 <» X a, 03 X5 01 x: a: OJ 5f -1^ ^ © T. ft -5j J2 rt '^ +j ^ F*^ 1 \* .Wings spread 2^ in. Dingy -white, light- ly streaked and blotched with blackish. No brush of brown hairs at tip of ab- domen. Does not fly, crawls. Winter Passed in ^gg stage— see above. Never as a caterpillar. Irritation of Human Skin Not caused by any stage. Most Effective Means of Control. Soak eggs with creosote in fall, winter, or spring. AND BROWN-TAIL MOTH CONTRASTED. Brown-Tail Moth. Stages. A.lways on uuder side of leaf. Smaller and more slender. Dark or golden brown. July. Egg Cluster. Bright tawny or orange. A conspicuous row of pure white spots or dashes along each side of body. Only two bright red spots on middle line at lower end of back. Caterpillar. Wings spread li inches. Pure snow white. Moth, Female. A conspicuous, sharply con- trasted, thick tuft or patch of golden or brownish hairs at tip of abdomen. A swift, strong flyer, by night, and attracted to lights. :^.- ^vi&^«>* As small caterpillars in a silken web or nest on tips of tw gs, from which they crawl out in spring. Winter Passed. Irritation. Hairs from caterpillars, which are often transferred to cocoons and moths, cause an annoying and painful irrita- tion of the skin. Most Effective Means of Control. Cut off and burn webs in winter. THE PRESENT CONDITION OF THE GIPSY MOTH IN NEW HAMPSHIRE. In the fall of 1905 a rough scout of the seacoast towns of New Hampshire which are most accessible by through travel from the areas in Massachusetts most infested by the gipsy moth was made by two men employed in the work for a few weeks only. In the course of this scout the moth was dis- covered in all of these towns from the Massachusetts line to Portsmouth, but always in small colonies only. This work was done under the direction of Professor Sanderson, at the expense of the state of New Hampshire, and one of the inspectors was borrowed from the Massachusetts force engaged in the work of suppressing the gipsy and brown- tail moths. The appropriation of the general government became available July 1, 1906, and in the latter part of that month scouting work was begun by government employees in New Hampshire. One man was sent to the state at first and on August 12 another was furnished. Systematic scouting was at once begun in the towns in which the moth was discovered the previous year, with the following result : In Seabrook were found twenty colonies and more than 300 egg-clusters ; in Hampton Falls fifteen colonies and a total of 140 egg- clusters; in Hampton nearly sixty colonies and over 550 egg-clusters; in North Hampton over forty colonies and about 400 egg-clusters, and in Rye about seventy-five colonies and over 1,400 egg-clusters. Curiously enough, this record would seem to indicate that the gipsy moth is more plentiful as the distance increases from the badly infested centers in Massachusetts, but this cannot be taken as a sound generalization, since when the scouting commenced in late July there were still many of the caterpillars crawling, and there are undoubt- edly very many egg-clusters in the first named towns which / * /EPSOM / \ / V \ ••"■»■ /bow y /NORTHWOooVBARRlNJi^TON A^ O v^.-r \ /--/ ' -OWN l^'"' 7 : V"-^"""'^ >v,'tan«MTo» /«lTo»i \ \ /milTOKi \ »A«NSTUO A. %-\ / -J^v R0CHC5T ROCHESTER VsTRAfTORO ,'n^ CANDIA PORTS- ^ TOWN /OEERFIELD ..-— ' y-fi ; '~~' /NOrriNeHAM /.EC /OURHAny iNcwmt- / /I TON IhOOKSEtt ; -r— --- '- ' T-^ew , /maRketV ' " 'reem-i — \i "'"■^■*> EXETER L ^/---i"'^ J-* I ScmfstTr >REMON^lBREi;^, © •^?/'"'"" i ' *- ' /CHESTER ; "WOOD > yMAMPro!>~_ .•RAYMONO-' EPP'NC ;5,^'Sr,; <<, 'AUBURN/ l LONDON-", OERRr X~-^,__J..^^ ':^*'l^,l\il&7^ r \y WINOH/»M ) /SAIEM I E>W« I /'PEl)h*m";V'EThSen /-. 0"/< ^V 1/lBBiCTONA' .,^-^- . 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