BTATE PIt.ANT 3OAXRD
THE INSECT PEST SURVEY
A periodical review of entomological conditions throughout the United States
issued on the first of each month from March to November, inclusive
Summary for 1926
INS EC T PEST SURVEY BULLET IN
Vol. 6 Summary for 1926 No,6O
A summary of the insect conditions for the year 1921 was ptublished
as a Departmental Bull1etin (U. S. D. A. Bulletin 1103). It was proposed
at that time to make this an annual feature, but owing to the rapid growth
of the survey work it was found impracticable to continue this feature, The
demand,however,fot this type of annual summary makes it desirable that each
year's entomological activities be reviewed by the Survey, We feel that the
present departure id issuing a 10th number to the annual volume of the Insect
Pest Survey will meet this requirement most satisfactorily.
ft considerable space was devoted to those introduced insects which
are the subjects of special investigations, as these are covered in annual
summaries from the offices in charge of these activities.
The most striking entomological feature of the year 1926 was the
widespread and destructive abundance of several species of cutworms. The late
spring was very probably responsible for the continued depredations of these
insects. The army cutworm (Chorizagrotis uxijiaris Grote) appeared in des-
tructive numbers in March in parts of Kansas, Nebraska, and Cklahema. During
April this cutworm did very considerable damage to wheat and alfalfa. Similar
reports of injury by cutworms early in the season were received from the south-
eastern and Gulf States. In May a very unusual outbreak of -the variegted
cutworm (Lycovhotia mararitosa var. saucia Hbn.) was reported from the Gulf
region of Mississippi and Texas. Depredations of cutworms continued through-.
out early June, particularly in the Chio and upper Mississippi River Valleys,
and the damage extended into early July, when the rea-backed cutworm (uxoa
ochrogaster Gne), the pale western cutworm (Porosagrotis orthonia Morr.),
the early cutworm (B oa tristicula Morr.), and Buma -eeliens Grt., were
reported as the most important insects of the season in Saskatchewan, Alberta,
British Columbia, Manitoba,and southern Ontario.
CERFAL AMD FORAE CROP INSECTS"
The late fall and winter surveys of 1925-26 indicated that the Hessian
fly was at a very lov stage of its abundance in the Middle Atlantic and South-
Central States, as well as *in the Lake region, with the possible exception of
Illinois. This low ebb seemed to extend southward through Missouri and westward
to Nebraska and South Dakota. The situation in Kansas, however, appeared
much more critical, while on the Pacific Coast the conditions of the Best
were repeated. As the season advanced the forecast was, in general, borne
out, but little commercial damage being reported from any part of the wheat
belt except Kansas, During July, however, the fly was observed to be decidedly
more abundant in west-central Ohio and the northern two-thirds of Indiana.
The fall surveys indicate that it has increased from 1,5 per cent in 1925
to 3.6 per cent in 1926 in New York State and from 7,5 per cent to 8.8 per
cent in Ohio; but in Illinois the fall surveys indicate a decrease in the
abundance of this insect. In general, the fly is not appearing in threatening
numbers east of Kansas. A rather unusual situation developed in Pennsylvania,
where the flies in volunteer v-heat emerged this fall, infesting grain sown
alter the fly-free date. Usually these flies do not emerge until the following
spring. Another interesting development of the year was the discovery of this
pest on the tast coast of New Brunswick, in Northumberland County, about 100
miles from the St. Johns River Valley.
Brood "A" of white grubs emerged as prognosticated. Heavy flights were
observed during May in southern Illinois, parts of Indiana, Iowa, Missouri,
Kansas and Mississippi. The larvae of these insects were in general less
prevalent and destructive than usual in the United States, but in southern
Ontario the damage caused by them seems to have materially increased over
that in 1925,
The chinch bug passed the winter with slight mortality. During May it
was reported as unusually abundant in central and south-central Illinois
and in parts of Kansas. The outbreak in Mississippi reported last year does
not seem to have abated. In general, however, damage by the chinch bug
was not serious, although scattered outbreaks were reported from Mississippi,
and rather intense infestations from southeastern and southern Nebraska, parts
of Kansas, and central Missouri. Owing to the lateness of the season the
movement of the chinch bug from small grain to corn was delayed until early
in July. At that time the situation seemed rather serious in the Ohio River
Valley and westward to NITebraska and Kansas. Heavy rains in the East however,
materially checked this insect, and present indications are that in the Ohio
River Valley it will go into hibernation in materially reduced numbers; in the
part of the chinch bug belt west of the Mississippi River it will in all
probability enter the winter in 1arge numbers,
The green bug (Toxoptera graminum Rond.) appeared in March. in -onl3 small
and localized areas in the southern part of its range; small areas were found
infested near Sherman and Rochelle, Tex. 1arly in April a single outbreak
was reported from Logan County, Okla. In the northern part of its range,
however, in Ohio, Indiana, Micbigan, Minnesota, South Dakota, Wisconsin and
Iowa, it appeared in rather conspicuous numbers, but the damage except in
Minnesota was not serious.
Grasshoppers in general were not in 1926 unusually abundant in the United
States. In British Columbia, however, serious outbreaks occurred, particularly
in the Peaae River and Chilcotin districts.
Tireworms (Elateridae) were reported from many scattering localities.
No unusually serious damage, ho-ever, was recorded from the United States. In
the Provinces of Saskatchewvan and Alberta these insects have since 1923
continued to increase in both numbers and importance as crop pests.
The ELropean corn borer (Pyausta nubilalis Hbn.) in its originally
infested area in New York State has increased 300 per cent in intensity over
the popyTlation records of 1924. The total area found to be infested by it
has during the season almost doubled and now extends westward to Berrien
County, Mich.,and Noble County, Ind. One corn borer was found just over
the Indiana.- Illinois line in Zanriakee County, Ill.
The fall armyworm (La-phM frugiperda S. & A.) was more or less destructive
throughout the season, Reports of heavy damage have been received from South
Carolina, Georgia, Mississippi, and southern Louisiana.
The corn ear worm (Heliothis obsoleta Fab.) was decidedly troublesome over
the greater part of the country. Exceptional damage has been reported from
North Carolina, South Carolina, Georgia, Alabama, Iowa, Nebraska, Kansas,
Indiana, Illinois,and Missouri. Corn suffered the major damage, as usual,
but in the peach belt of Georgia the entire crop of peaches on a 4,000-tree
plantation was destroyed.
Slight and unimportant outbreaks of the armyworm (Cirphis untmncta Haw.)
were recDrded from the East-Central States.
The sugarcane beetle (Raetheola ruice's Lec.) was so serious in the Gulf
region that in many cases replanting of corn was necessary, and in 1926 it
appeared for the first time as a serious porn pest in Illi4ois.
The grape colaspis (Colaspis brunnea Fab.) was an unusually serious anemy
of corn in the East-Central States#
The stalk borer (Papaiema nitela Gaen.) was one of the outstanding
pests of the year tin the region extending from Ohio through Indiana and Illinois,
westward to Nebraska and Iowa, and southwestward into Missouri and Kansas.
The alfalfa weevil (Phytonomus 1posticus Gyll.) has been found in Goshen
and Carbon Counties, Wyo., near the Nebraska State Line, and in four additional
counties in Colorado*
The joint worm (Harmolita tritici Fitch) was reported for the first time
as serious in the Pacific Northwest, an area about 12 miles square in Clackamas
and Marion Counties, Ore.,being very heavily infested. Inasmuch as stubble
from this general region has been examined for the past 8 years in connection
with. Hessian fly work, this insect is undoubtedly new to this particular
The season seems to have favored unusual northern extension of the range
of a number of important pests. The sugar-cane beetle and the green bug have
been mentioned. The southern corn stalk borer (Diatraea zeacolella Dyar)
occurred in serious numbers in a restricted region about Racine, Wis,
The wheat stem sawfly (Cpghua 1paeus L.) infested from 1 to 50 per
cent of the wheat throughout southwestern Manitoba and southcentral Alberta,
and has caused u wia Ilyheavy damage in southern Saskatchewan.
One of the most striking features in connection with insects affecting
deciduous fruit ws the remarkably small population of aphids throughout New
England and the Middle Atlantic States, and in the LIississippi Valley. In the
latter region eggs were very generally less prevalent than usual. In the
Southeastern States, on the other hand,the rosy apple aphid (Anuraphis roseus
Baker) was unusually abundant. The small population of aphids in the greater
part of the deciduous fruit belt continued throughout the season. Reports
from the Niagra District of Ontario and the Annapolis Valley in Nova Scotia
indicate that the scarcity of these insects also prevailed over those regions.
Reports in the early spring indicated that the codling moth (Carpocapsa
pomonella L. ) passed the winter in unusually la .'ge numbers over the greater
part of its range. The only exception wts the Pacific Northwest. LDter
developments show that this pest was more seriously prevalent than in years
in parts of the eastern fruit belt, in many cases doing very serious damage
even under good spraying practise.
The oriental fruit moth (Las-peyresia molest Busck) has been less serious
than usual over the greater part of its range. In the Georgia peach belt
it produced one brood less than in 1925. Larvae of what are believed to be
this insect were found at Dast Lansing, Mich.,in the season of 1926. It was
also discovered in the Niagara district, Ont., in October, 1925, in peach
orchards at St. Davids, Peachland, Vineland Station, and Bartonville, thus
indicating either a somewhat general or a patchy infestation extending from
Hamilton to the Niangara river. Fortunately, the infestation is at present
The European red mite (Ppratetranychus pilosus C, & F.) is now known
to occur in the Shenandoah Valley, Virginia, this being its southernmost
A rather unusual infestation by the boxelder bug (Leptocoris trivittatus
Say) has been reported from the State of Washington,the bugs doing considerable
damage by puncturing the fruit of apples. This insect has been reported for
the first time from North Carolina,
The eastern tent caterpillar (Malacosoma Pmericana Fab.) was generally
abundant from the Connecticut River Valley westward to New York State and
southward to Virginia; to the north it extended in unusual numbers into
parts of southern Quebec and New Brunswick, Canada.
The San Jose scale (Aspidiotus perniciosus Comnst.) was in 1926 slightly
mere prevalent in the New England States than it was a few years agD, "hereas
the general uprard trend noted in New York State and Pennsylvania for the
last few years seems to have passed its crest and is receding. In the south-
eastern States the scale is decidedly more serious than usual, and appears
to be on the increase in the Bast-Central States. Over the rest of its range
it appears to be under satisfactory control, and in the Pacific Northwest
is subnormal; this latter condition is believed to hlive been brought about
by the severe winter of 1924...25.
The plum curculio (Conotrachelus nenuphar Hbst.) as a whole was
less prevalent than usual. Reports of serious d.amrge, however, were received
from Indiana and Missouri, and also from sections of southern Quebec and
The cambium curculio (Conotrachelus anaglypticus Say) appeared in
3ne of the most serious insect outbreaks that has ever occurred in the pecan-
growing sections of southern Mississippi. The walnut caterpillar (fatana
integerrima Go & R. ) was much more numerous than usual over the entire eastern
pecan section, from Florida to Mississippi.
The citrus aphid situation in Florida has very materially improved.
Very slight infestations were observed over the entire region previously so serio'sl
infested. A single serious infestation was reported from Louisiana.
TRUCK CROQP INSECTS
The harlequin bug (Murgantia histrionics Hahn) was decidedly more
troublesome than usual over the South Atlantic and Gulf region.
The cabbage maggot (HylemAya brassicae Douche) was in 1926 generally
destructive from Massachusetts through the Zast-Oentral States to Wisconsin
The known distribution of the Mexican bean beetle (Epilachna corrupt
Mule.) has very materially increased during the past year. It was reported,
for the first time in the State of Maryland, in Garrett and Washington Counties.
In Virginia the insect has advanced to very nearly the eastern border of the
State in Frederick, Pagesnd Culpeper Counties. In Norith Carolina it has
reached the center of the State in Casewell County, and in Ohio the extension
along the lake is now complete. In Indiana it has spread -estward to Clinton
County, and in Pennsylvania it has been found as far East as Dauphin County,
near Harrisburg, and north to Ven-ingo Coanty.
The bean aphid (h-phis rumicis L.) developed in unprecedented
numbers in the cannery bean sections of Ohio, where it caused considerable
losses to growers of lima and string beans.
In southern Utah the beet leafhopper (3utettix tenella Baker)
was epidemic in 1926, and because of curly top the beet crop was practically
The campaign for the control of the sweet potato weevil in the
Gulf region of Mississippi lnd Alabama has been so successful that where 123
farms in Pearl River County, Miss,, vere infested in 1923 but one fvrm was
found infested it 1926, and where 62 farms in BIdwin County, Ala., were
found infested in 1925, but two showed any infestation this year.
The turnip weevil (Listroderes obliouus 'Gyll.) was for the first
time reported from California, where it was found seriously infesting c-rrots,
spinach, and other grden truck at San Jose. In the eastern area of infestation
by this insect the situation has changed but itttle since last year. The
closely related species Listroderes a!picalis Waterh. was found for the first
time in the State of Mississippi, Up to this year this species hlrs been
confined to Louisiana.
The sweet potato beetle (T2.ophorus viridicyaneus Cr.) has been
reported as damaging sweet potatoes in WIalker Oonfy, Ga, This insect has
STATE PLANT BOARD
for .a number of years been known as infesting the sweet potato, but has not
heretofore been recognized as of much importance.
In Mississippi during the past season the sugarcane beetle (1hetheola
rugiceps Lec.) caused very unusual d.-mage to sweet potatoes, as high as
26 per cent of the tubers in three lots examined by the inspectors being
The coffee bean weevil (Araecerus fasciculatus DeG.) has been found working
on sweet potatoes in storage near Foley, Ala.
The pepper weevil (nthonomus euenii Cano) is now one of the most
important pests in the pepper-growing sections of Orange County, Calif. ,where
losses have run as high as 50 to 65 per cent of the crop. Approximately 8,000
acres of peppers are grown annually in this county.
The spotted asparagus beetle (Crioceris duodecimpunctata L.) was in 1926
collected for the first time in the State of Illinoise. It appeared in students'
collections, in the fall of 1925, from Lake, Piatt, and Champaign Counties.
Inasmuch as very extensive collections have since 1922 been made annually
over this same region, this insect is undoubtedly a quite recent arrival, This
is the westernmost record for the spotted asparagus beetle, despite the fact
that its distribution is usually considered the same as that of Crioceris
The Colorado potato beetle (Loetinotrsa decemlineata Say) was generally
about normal to suTbnormal throughout its entire range, This condition alse
prevailed throughout Canada, with the exception of a small region in southern
Quebec and in southern Alberta.
The potato leafhopper (gporasca nmli LeBw) was decidedly more serious than
usual in Indiana and Illinois, and in the Niagnra district of Ontario.
The pea aphid (!llinola psi KAtlt.) was very numerous in the cannery
pea sections of Mine and southward to eastern Massachusetts; also in the
pea-canning sections of western New York and southern Minnesota,
A flight of the painted lady (Vanessa cprdui L.), similar to the one
reported in 1924, occurred in California this year in Mrch. In April the
larvae were troublesome on lettuce and prunes in parts of that StF.te.
.'rom the moss examinations marda it was evident that the initial infes-
tation of the boll weevil (Anthonomus grnndis Boh.) in Louisiana would be
heavier this year than last, and much hep.avier in the southern than in the
northern part of that St-te. TheS Mississippi Valley territory in general
was rather heavily stocked with hibernating weevils, the infestation decreasing
to the eastward, but with enough weevils present to do serious damage under
favorable summer weather conditions, rIn Texas the weevil population was so
reduced over a large part of the State that very abnormal weather would be
required to cause serious damage. Tb emamargonce of the wecvil in the spring
was extremely slow in practicaly the entire cotton bolt; as the season advanced
the infestation was generally low in Texas, Oklahoma, and Arkansas, but decidedly
heavier than normal in Louisiana. It was more general than usual in Mississippi,
though the intensity there was lower than usual, Eastlard throughout Alabama
and Georgia the infestation was generally low. As the season advanced further
the insect developed no serious aspects except in Louisiana, Mississippi, and
southern Alabama. Late in the season, ho-ever, considerable damage -7as done to
the top crop, but the main crop as a hole was not seriously affected.
The cotton flea hopper (Qsallus seriatus Reut.) occasioned very considerable
excitement in July in Texas, Oklahoma, Louis iana,and Mississippi, extending
eastward to Georgia, South Carolina, and North Carolina. The outbreak, however,
was of short duration, and not so serious as anticipated except locally.
The cotton boll worm (Heliothis obsoleta Fab.) was somewhat more trouble-
some than usual throughout the cotton belt, extending from North Carolina to Texas.
The year 1926 marks one of the unusual advances of the cotton leaf -orm
(Alabama ariliacea Hbn.) into the northern States, Late in May pupae and recently
emerged adults 7ere quite numerous in Wharton County, Tex. These continued to
multiply during June in south-central Texas. Heavy flights took place from this
center in the early part of July, and up to July 6, larvae were appearing in
northern Mississippi, Louisiana, and Arkansas. From this new center a brood
appeared about September 1 and swept northward, being recorded in Michigan on
the 5th, in New York on the 7th, and Massachusetts on the 12th. The moths con-
tinued to drift into the Vpper Mississippi Valley and eastern States in increasing
numbers throughout the month. By the middle of September the larvae of this
last brood "ere stripping the cotton in Georgia and South Carolina. In the Ohio
River Valley in Indiana and Illinois the moths did considerable damage to peach,
grape, apples ,and tomatoes. The insect rwas so numerous in parts of Mississippi
that at one point where their march was impeded by a road the stench of their
decaying bodies attracted turkey buzzards, and in certain cities and to-ms in
Pennsylvania and Massachusetts the enormous numbers of the moths caused con-
siderable alaTm among residents. The most unusual feature of this northern
flight was recorded in October, rhen a brood of larvae from these moths was found
on the experimental cotton plots at Arlington Farm, near Washington, D. C., and
on cotton plants at Monroe, Mich. Thsicinsect has never been recorded heretofore
as producing larvae in the northern States.
GF3EWHOTJSE AND OENAMETTAL PLANTS
Among the insects affecting greenhouse ind ornamental plants wre may
mention the finding of the sawfly Allantus mellipes Norton at Moncton, New Bruns-
wick; and the finding of the lilac leaf miner (Gracilaria syringella Fab.)
for the first time at Vancouver, British Columbia.
The rose chafer (Yacrodactylus subspinosus P'ab.) :-as generally below norm-.,.
in population in New Eglmand and the Middle Atlantic States, the only report of
its occurrence in serious numbers having been received from lebraska.
FOERST AID SHADE TREE INSECTS
Among the forest and shade-tree insects the bagworm (Thyrido-oteryg
ephemeraeformnis Ha7.,was quite generally reported from the Eist-Central and
Southeastern States. The birch leaf miner (FZnusa pamila Klug) again seriously
damaged the foliage of birches in southern New York and Connecticut. The
hemlock spanworm (Ello-ia fiscellaria Guen.) is still seriously infesting hemlock
and balsam fir in Wisconsin.
On the Beaverhead-Bitterroot National Forests in Montana there exists one
of the largest epidemics of the mountain pine beetle (Dendroctonus monticola
Hopk.) that has ever been recorded. Ihis epidemic has been going on almost
continuously since 1909 but until very recently it has been in unmerchantable
A serious outbreak of the Black Hills beetle (Dendroctonus ponderosae Hopk.)
has suddenly come into prominence in the Colorado National Forest, Colo. Approxi-
mately 350 square miles are involved. Last year the infestation increased 500
per cent. The epidemic of this beetle in the Kaibab National Forest, Ariz.,
has completely subsided.
In southern Oregon in the vicinity of Elamath Lakes the western pine
beetle (Dendroctonums breviccp"is Lec,) has again increased in prominence. Private
companies are undertaking control during the present winter and spring.
Brood XVII of the periodical cicada (Tibicina septendecim L.) is one of the
problematical broods with but few well-developed colonies reported, It has
been reported from Virginia, Georgia, Iowa, Missouri,and New York, but none
of the records have ever been confirmed. In 1926 authentically determined
specimens were taken from Doniphan County, Kans. ,about 100 miles north of the
nearest previously recorded locality for this brood, in Cass County, Mo. This
was the only record of the appearance of this insect in 1926.
INSECTS AFFECTING DOMESTIC ANIMALS
A very severe outbreak of the stable fly (Stomoxys calcitrans L.).believed
to have been the most severe since the unprecedented conditions of 1912, occurred
throughout the grain belt of northern Texas and southern Oklahoma. During its
height dairymen reported a reduction of milk flow &f from 5 to 80 per ce~t, farm
work was discontinued, and meat animals were rushed to market on account of
loss of weight. 1s was the case in the earlier severe outbreak mentioned, a
large grain erop, with the production of a surplus of straw, followed by wet
weather, brought about conditions very favorable for the breeding of flies in
MISC LATUS PESTS
The number of reports being received by the Insect Pest Survey of dcnage
done to buildings and other woodwrork by termites has increased every year since
the Survey started. This is possibly o-'ing to an increased interest in the
damage done by these pests.
Among the newer pests that have come to our attention during the year
is one of prunes, a small moth (,Aieola scitulella Dyar) reported from Idaho.
The scale insect. Lecanin ccr'._ii L<.L has occurred in very serious numbers
in the western part of the State of Washington, as has also the satin moth
(Stil-pnotia salics L.). The black vine weevil (Brachyrhinus sulcatus Fab.)
has been found for the first time in southern California, and the eggplant
le.-f miner (Phthorimnaea glochinella Zeller) was also recorded from this
region for the first time.
In Nay,1922, the Insect Pest Survey received a report of the weevil
G1yptoscelis squamuilata Crotdh, damaging grapes in southern Nevada. In
1925 this pest was reported from the Coachella Valley, in California, and
in 1926 it was reported as doing damage in the Imperial Valley, the adult
beetles eating into the unfolding buds of grapes.
A new scarabaeid beetle (Autoserica castansa Arrow) was recorded
for the firsb time from North America$ in the vicinity of greater New York,
0Ce of the most significant developments of 1926 was the extension
of territory known to be infested by the Anomala (Anomala orientalis Waterh.),
rhich is now found in the southern part of New York State, on Long Island,
and in southern Connecticut.
The Japanese beetle (Popillia Japonica Nevn.) has extended its range
fro its original territory in eastern Pennsylvania westward to Harrisburg
and northward to FEston. It has also been found in the Hudson River Valley
as far north as Ossining, southward to Stamford, Conn., and* to Long Island.
- r -. "2
UNIVERSITY OF FLORIDA
3 1262 09244 5419 I