,transcriber ,note    ,text emphasis    
denoted as ,italics and ,bold4 ,whole   
and fractional parts  of numbers as     
#abc-d_/e4                              
,,flytraps ,,and ,,their ,,operation    
,f4 ,c4 ,,bishopp                       
,entomologist1 ,investigations of       
,insects ,affecting the                 
,health of ,animals                     
,illustration                           
,,farmers' ,,bulletin #gcd              
,,united ,,states ,,department ,,of     
,,agriculture                           
,contribution from the ,bureau of       
,entomology                             
,l4 ,o4 ,,howard1 ,chief                
,washington1 ,d4 ,c4   ,issued ,june    
#aj1 #aiaf2 second revision1 ,march1    
#aiba4      ,show this bulletin to a    
neighbor4 ,additional copies may be     
obtained free  from the ,division of    
,publications1 ,united ,states          
,department of ,agriculture             
,,washington 3 ,,government ,,printing  
,,office 3 #aiba      ,,results obtained

 in experiments with the use of         
chemicals against fly  larv in manure   
are presented in ,bulletins ,nos4 #aah1 
#bde1 and #djh of the  ,department of   
,agriculture4 ,the biology of the house 
fly and the various  methods of control 
are discussed in ,farmers' ,bulletin    
#hea4    ,this bulletin is intended to  
give directions for the use of a        
supplementary means of controlling      
flies4 ,it is adapted to all parts of   
the ,united ,states4          ,,flytraps
 ,,and ,,their ,,operation4             
,,contents4                             
,page4      ,uses and limitations of    
flytraps               #c      ,kinds of
 flies caught                           
#c      ,types of traps                 
#d      ,trapping the screw-worm fly    
#ac      ,baits for traps               
#ac      ,bait containers               
#ae      ,care and location of traps    
#ae      ,sticky fly papers             
#af      ,poisoned baits                
#af          ,caution                   

#af          ,,uses ,,and ,,limitations 
,,of ,,flytraps4      ,,flytraps have a 
distinct place in the control of the    
house fly and other  noxious fly        
species4 ,there is a general tendency1  
however1 for those  engaged in combating
 flies to put too much dependence on the
 flytrap  as a method of abating the    
nuisance4 ,it should be borne in mind   
that  flytrapping is only supplementary 
to other methods of control1 most       
notable of which is the prevention of   
breeding either by completely  disposing
 of breeding places or by treating the  
breeding material with  chemicals4      
,it may be said that there are two main 
ways in which flytraps are  valuable3   
7#a7 ,by catching flies which come to   
clean premises from  other places which 
are insanitary and 7#b7 by capturing    
those flies  which invariably escape in 
greater or less numbers the other means 
of  destruction which may be practiced4 
,furthermore1 the number of flies       
caught in traps serves as an index of   

the effectiveness of campaigns  against 
breeding places4    ,flytrapping should 
begin early in the spring if it is to be
 of greatest  value4 ,although          
comparatively few flies are caught in   
the early spring1  their destruction    
means the prevention of the development 
of myriads of  flies by midsummer4      
,,kinds ,,of ,,flies ,,caught4      ,the
 various species of flies which are     
commonly annoying about habitations  or 
where foodstuffs are being prepared may 
be divided roughly into two  classes3   
7#a7 ,those which breed in animal       
matter1 consisting mainly of the        
so-called blowflies1 including the      
screw-worm fly2#a and 7#b7 those which  
breed in vegetable as well as in animal 
matter4 ,in the latter group the  house 
fly#b is by far the most important4 ,the
 stable fly is strictly a  vegetable    
breeder1 as are also certain other      
species which occasionally  come into   
houses and in rare cases may contaminate
 foodstuffs4 ,the stable  fly1#c which  

breeds in cow manure or decaying        
vegetable matter1 and the  horn fly1#d  
which breeds in manure1 are             
blood-sucking species1 and can be       
caught in ordinary flytraps in          
comparatively small numbers only4 ,the  
kind  of flies caught depends to a      
considerable extent on the material used
 for  bait4 ,in general the house fly   
and other species which breed in        
vegetable  matter are attracted to      
vegetable substances1 while the         
blowflies will  come most readily to    
animal matter4 ,this rule1 of course1 is
 not absolute1  as flies are less       
restricted in feeding than in breeding  
habits1 and1 as  is well known1 the     
house fly is attracted to a greater or  
less extent to  any moist material1     
especially if it has an odor4    #a     
,chrysomyia macellaria ,pab4    #b      
,musca domestica ,l4    #c ,stomoxys    
calcitrans ,l4    #d ,lyperosia irritans
 ,l4          ,,types ,,of ,,traps4     
,the same general principle is involved 

in nearly all flytraps in use1  though  
superficially they may appear quite     
different4 ,the flies are  attracted    
into a cage1 as it were1 by going       
through a passage the entrance  of which
 is large and the exit small1 so that   
there is little chance  of the flies1   
once in1 finding their way out again4   
,this principle is  modified to fit     
different conditions4 ,for instance1 the
 window trap1  devised by ,prof4 ,c4 ,f4
 ,hodge1 catches the flies as they      
endeavor to enter  or leave a building2 
the garbage-can trap1 for which ,prof4  
,hodge is also  to be credited1 catches 
the flies that have entered garbage     
cans2 and the  manure-box trap retains  
the flies bred from infested manure put 
into the  box4    ,the attractant used  
to induce flies to enter traps may      
consist of 7#a7  food1 as in baited     
traps2 7#b7 odors1 as in window traps   
placed in windows  from which odors are 
emitted2 and 7#c7 light1 as in traps on 
manure boxes4  ,of course1 light is an  

important factor in the success of all  
traps1 for1  as is well known1 flies    
have a marked tendency to go toward the 
light1 and  they usually enter the trap 
by flying toward the light after having 
been  attracted beneath it by bait or   
after entering a room in search of food4
      ,,conical ,,traps4    ,a number of
 traps of this general type are on the  
market1 but most of  these are of small 
size4 ,nearly all are constructed with a
 dome instead of  a cone1 and on this   
account the catching power is reduced   
about one-third4  ,moreover1 the farmer1
 dairyman1 or anyone with a few tools   
can construct  traps at a small fraction
 of the sale price of ready-made ones4  
,,the ,,conical ,,hoop ,,trap4    ,a    
trap which appears from extensive tests 
made by ,mr4 ,e4 ,w4 ,laake and the     
author to be best for effective         
trapping1 durability1 ease of           
construction  and repair1 and cheapness 
may be made as follows3                 
,illustration3 ,fig4 #a4--;,conical hoop

 flytrap1 side view4 ,a1 ,hoops  forming
 frame at bottom4 ,b1 ,hoops forming    
frame at top4 ,c1 ,top of trap  made of 
barrel head4 ,d1 ,strips around door4   
,e1 ,door frame4 ,f1 ,screen  on door4  
,g1 ,buttons holding door4 ,h1 ,screen  
on outside of trap4 ,i1  ,strips on side
 of trap between hoops4 ,j1 ,tips of    
these strips projecting  to form legs1  
,k4 ,cone4 ,l1 ,united edges of screen  
forming cone4 ,m1  ,aperture at apex of 
cone4    ,the trap consists essentially 
of a screen cylinder with a frame made  
of  barrel hoops1 in the bottom of which
 is inserted a screen cone4 ,the height 
of the cylinder is #bd inches1 the      
diameter #ah inches1 and the cone is #bb
  inches high1 and #ah inches in        
diameter at the base4 ,material         
necessary  for this trap consists of    
four new or secondhand wooden barrel    
hoops1 one  barrel head1 four laths1 #aj
 feet of strips #a to #a inches wide by 
one-half  inch thick 7portions of old   
boxes will suffice71 #fa linear inches  

of #ab  or #ad mesh galvanized screening
 #bd inches wide for the sides of the   
trap  and #da inches of screening #bf   
inches wide for the cone and door1 an   
ounce  of carpet tacks1 and two         
turn-buttons1 which may be made of wood4
 ,the  total cost of the material for   
this trap1 if all is bought new at      
retail  prices1 is about #a4 ,in        
practically all cases1 however1 the     
barrel hoops1  barrel head1 lath1 and   
strips can be obtained without expense4 
,this would  reduce the cost to that of 
the wire and tacks1 which would be #hj  
cents4  ,if a larger number of traps are
 constructed at one time1 the cost is   
considerably reduced4    ,one of these  
traps is illustrated in figures #a and  
#b4 ,in constructing the  trap two of   
the hoops are bent in a circle 7#ah     
inches in diameter on the  inside71 and 
nailed together1 the ends being trimmed 
to give a close fit4  ,these form the   
bottom of the frame 7,a71 and the other 
two1 prepared in  a similar way1 the top

 7,b74 ,the top 7,c7 of the trap is made
 of an  ordinary barrel head with the   
bevel edge sawed off sufficiently to    
cause  the head to fit closely in the   
hoops and allow secure nailing4 ,a      
square1  #aj inches on the side1 is cut 
out of the center of the top to form a  
door4  ,the portions of the top 7barrel 
head7 are held together by inch strips  
7,d7 placed around the opening one-half 
inch from the edge to form a  jamb for  
the door4 ,the door consists of a narrow
 frame 7,e7 covered with  screen 7,f7   
well fitted to the trap and held in     
place 7not hinged7 by  buttons 7,g74    
,the top is then nailed in the upper    
hoops and the sides  7,h7 formed by     
closely tacking screen wire on the      
outside of the hoops4  ,four laths 7,i7 
7or light strips7 are nailed to the     
hoops on the outside  of the trap to act
 as supports between the hoops1 and the 
ends are allowed  to project #a inch at 
the bottom to form legs 7,j74 ,the cone 
7,k7 is cut  from the screen and either 

sewed with fine wire or soldered where  
the  edges meet at 7,l71 or a narrow    
lath may be nailed along these edges4   
,the apex of the cone is then cut off to
 give an aperture 7,m7 #a inch in       
diameter4 ,it is then inserted in the   
trap and closely tacked to the hoop     
around the base4    ,illustration3 ,fig4
 #b4--;,conical hoop flytrap1 top view4 
,letters designate  parts as in figure  
#a4    ,the construction of a cone of   
any given height or diameter is quite   
simple  if the following method be      
observed4 ,it is best to cut a pattern  
from a  large piece of heavy paper1     
cardboard1 or tin1 ,figure #c           
illustrates the  method of laying out a 
cone of the proper dimensions for the   
above trap4  ,an ordinary square is     
placed on the material from which the   
pattern is to  be cut2 a distance 7#bb  
inches7 equal to the height of the cone 
is laid  off on one leg of the square at
 ,a1 and a distance 7#i inches7 equal to
  one-half of the diameter of the base  

of the cone is laid off on the other    
leg at ,b1 and a line is drawn between  
the points ,a and ,b4 ,with the         
distance between these points as a      
radius and with the point ,a as a       
center1 the portion of a circle1 ,c ,d1 
is drawn4 ,with a pair of dividers1  the
 legs of which are set #a inch apart1 or
 with the square1 lay off as  many      
inches on the arc ,c ,d1 starting at ,c1
 as there are inches around  the base of
 the cone1 which in this case is about  
#ef inches1 reaching  nearly to the     
point ,e4 ,then add one-half inch for   
the lapping of the  edges of the cone1  
and one-half inch which is taken up when
 the cone is  tacked in1 thus making a  
total distance from ,c to ,e of #eg     
inches4  ,draw a line from ,a to ,c and 
another from ,a to ,e1 and cut out the  
pattern on these lines and on the arc   
from ,c to as shown in figure  #c4 ,the 
edges ,,ac and ,,ae are then brought    
together1 lapped one-half  inch1 and    
sewed with wire or soldered4 ,after the 

aperture of the cone is  formed by      
cutting off the apex1 as previously     
described1 it is ready for  insertion in
 the trap4    ,illustration3 ,fig4      
#c4--,method of laying out a pattern for
 the  construction of a cone4 ,cut out  
on curved line ,c to ,e and on dotted   
lines from ,a to ,c and ,a to ,e4    ,in
 order to figure the distance around the
 base of a cone of any given  diameter  
multiply the diameter by #c4adaf or     
#c-a_/g4    ,the height of the legs of  
the trap1 the height of the cone1 and   
the size  of the aperture in the top of 
the cone1 each are of importance in     
securing  the greatest efficiency4      
,,other ,,forms ,,of ,,conical ,,traps4 
,a modification of the previously       
described trap has been made by ,mr4 ,d4
 ,c4  ,parman of the ,bureau of         
,entomology4 ,the principal point of    
advantage in  this type is that it can  
be made more quickly and with fewer     
tools4 ,the  principles and dimensions  
are the same1 the most striking         

difference being  the absence of a      
wooden top4 ,a single hoop with the     
thick edge down forms  the upper frame  
of the cylinder and the entire top is   
made of screen4  ,a circular piece of   
screen with a diameter about #c inches  
greater than  the diameter of the       
cylinder is cut2 a hoop with a diameter 
equal to the  inside of the top of the  
trap is then made of heavy wire and laid
 upon the  disk of screen and the edges 
of the screen bent in over it4 ,by      
folding in  and crimping the edges of   
the wire over the wire hoop it will     
remain in  position without difficulty  
and the edges of the screen disk are    
used to  lift the top of the trap out   
for emptying flies4 ,it is important to 
have  the screen top fit the inside of  
the cylinder very snugly at all points4 
,if there is any space left where flies 
can escape it is a good plan to  bind   
the edge of the top with a strip of     
burlap4 ,this not only helps  to close  
the openings but keeps the hoop in place

 and aids in removing  the top4 ,another
 difference is that the screen forming  
the sides of the  cylinder is placed on 
the inside of the hoops and legs1 the   
frame being  built first and then the   
cylinder formed by tacking the wire on  
the inside  of the hoops and nailing in 
along the upright strips and against the
 wire  short pieces of laths with their 
upper ends against the lower edge of the
  hoop forming the top of the trap and  
extending downward along the legs  about
 two-thirds of their length4 ,these     
strips hold the wire in place and  give 
rigidity to the trap1 and they are thick
 enough to project beyond the  inner    
surface of the hoop and form a support  
upon which the edges of the  screen top 
rest4    ,illustration3 ,fig4 #d4--,tent
 flytrap4 ,when the trap is set up the  
screen  box4 ,a1 fits on the base1 ,b1  
and two pans of bait are placed beneath 
the tent4 ,c1 ,hole in screen at apex of
 tent4    ,conical traps with steel     
frames are satisfactory1 but they are   

less easily  rescreened4 ,these1 of     
course1 can be constructed only by shops
 with  considerable equipment4 ,traps   
constructed with a wooden disk about the
  base of the cone1 and a similar disk  
around the top to serve as a frame1  or 
those with a square wooden frame at the 
bottom and top1 with strips up  the     
corners1 are fairly satisfactory4 ,it   
should be borne in mind that the  factor
 which determines the number of flies   
caught is the diameter of the  base of  
the cone1 if other things are equal4    
,therefore the space taken up  by the   
wooden framework is largely wasted1 and 
if it is too wide it will  have a       
deterrent effect on the flies which come
 toward the bait4 ,for this  reason it  
is advisable that the wood around the   
base of the cone should be  as narrow as
 consistent with strength--usually about
 #c inches4    ,under no condition      
should the sides or top of the trap be  
of solid  material1 as the elimination  
of light from the top or sides has been 

found to decrease the catch from #ej to 
#ge per cent4      ,,tent ,,traps4      
,the tent form of trap has been widely  
advocated in this country1 but  recent  
experiments indicate that it is much    
less efficient than the cone  trap1 and 
usually as difficult to construct and   
almost as expensive4 ,the  size of these
 traps may vary considerably1 but one   
constructed according  to the dimensions
 given in figure #d will be found most  
convenient4 ,the  height of the tent    
should be about equal to the width of   
the base1 and the  holes 7,c7 along the 
apex of the tent should be one-half to  
three-fourths  of an inch in diameter   
and #a inch apart4 ,the box 7,a7 should 
be provided  with hooks to pass through 
the eyes on the base 7,b74 ,small blocks
 #a inch  thick are nailed beneath the  
corners of the tent frame to serve as   
legs4      ,,garbage-,,can ,,traps4     
,as previously mentioned4 ,prof4 ,hodge 
has adapted the cone trap to use on  the
 lids of garbage cans4 ,it is not       

advisable to use this trap except  where
 garbage cans are sufficiently open to  
admit flies4 ,in such cases a  hole may 
be cut in the lid of the can and one of 
the small balloon traps  which are      
obtainable on the market attached over  
the hole4 ,to make the  trap effective  
the edges of this lid should extend well
 down over the top  of the can4 ,the lid
 should be held up slightly so as to    
allow the flies  to pass under1 but not 
high enough to admit direct light4      
,practically  speaking1 the garbage     
forms the bait for this trap1 and when  
inside the  can the flies are attracted 
to the light admitted through the trap4 
,it  is really advisable to have the    
garbage cans fly proof1 so as to prevent
  danger of fly breeding within them    
rather than to depend on traps on the   
lids1 which necessarily allow odors to  
escape4 ,a garbage can with a trap      
attached is illustrated in figure #e4   
,illustration3 ,fig4 #e4--,top of       
garbage can with small balloon flytrap  

attached4      ,,manure-,,box ,,traps4  
,manure pits or boxes are desirable for 
the temporary storage of manure1        
especially in towns and cities4 ,these  
have been widely advocated1 but the     
difficulty has been that manure often   
becomes infested before it is put  into 
them1 and flies frequently breed out    
before the boxes are emptied and  often 
escape through the cracks4 ,to obviate  
these difficulties a manure  box or pit1
 with a modified tent trap or cone trap 
attached1 is desirable4  ,mr4 ,arthur   
,swaim1 of ,florida1 has devised a form 
of manure trap consisting  of a series  
of screen tents with exit holes along   
the ridges of these1  over which is a   
screen box4 ,the latter retains the     
flies as they pass  through the holes in
 the tents4 ,the entire trap is         
removable4    ,in order to retain the   
fertilizing value of manure to the      
greatest extent  it is advisable to     
exclude the air from it as much as      
possible and to  protect it from the    

leaching action of rains4 ,this being   
the case1 there  is really no necessity 
to cover a large portion of the top of  
the box with  a trap1 but merely to have
 holes large enough to attract flies to 
the  light1 and cover these holes with  
ordinary conical traps1 with the legs   
cut off1 so the bottom of the trap will 
fit closely to the box4 ,the same       
arrangement can be made where manure is 
kept in a pit4 ,in large bins two  or   
more holes covered with traps should be 
provided for the escape of the  flies4  
,manure boxes should be used by all     
stock owners in towns and cities1 and   
they are also adaptable to farms4 ,the  
size of the manure bin should be        
governed by the individual needs1 but   
for use on the farm it is desirable  to 
make it large enough to hold all of the 
manure produced during the  busiest     
season of the year4 ,a box #ad feet     
long1 #aj feet wide1 and #d feet  deep  
will hold the manure produced by two    
horses during about five months4  ,about

 #b cubic feet of box space should be   
allowed for each horse per day4  ,the   
bin should be made of concrete or heavy 
plank4 ,when the latter is used  the    
cracks should be battened to prevent the
 escape of flies4 ,the bin may  have a  
floor or it may be set in the ground    
several inches and the dirt  closely    
banked around the outside4 ,for the     
admission of the manure a  good-sized   
door should be provided in either end of
 a large bin4 ,a portion  of the top    
should be made easily removable for     
convenience in emptying the  box1 or one
 entire end of the box may be hinged4   
,on account of the danger  of the door  
being left open through carelessness1 it
 is advisable to  arrange a lift door   
which can be opened by placing the foot 
on a treadle  as the manure is shoveled 
in4 ,the door should be heavy enough to 
close  automatically when the treadle is
 released4 ,a manure bin with flytrap   
attached is shown in figure #f4         
,illustration3 ,fig4 #f4--,use of       

flytrap in connection with manure bin4  
,a1  ,block of wood set in ground to    
which lever raising door is hinged4     
,attention is directed to a maggot trap 
devised by ,mr4 ,r4 ,h4 ,hutchison1 as  
described in ,farmers' ,bulletin #hea of
 the ,department of ,agriculture4 ,where
  large quantities of manure are        
produced on a farm this method of       
storing  the manure on a platform and   
trapping the maggots which breed out may
 be  more convenient than the manure    
bin4      ,,window ,,traps4    ,prof4   
,c4 ,f4 ,hodge has designed a trap which
 is really a modified tent  trap adapted
 to use in a window4 ,this trap is      
constructed so as to catch  the flies as
 they enter or leave through the window4
 ,it is adaptable to  barns which are   
fairly free from cracks or other places 
where flies may  enter4 ,it may also be 
used on windows of buildings where      
foodstuffs are  prepared and where flies
 endeavor to enter through the windows  
or escape  after having gained entrance 

through other passageways4 ,all openings
 not  provided with traps should be     
closely screened1 and on large buildings
  traps may be installed in every third 
window4    ,illustration3 ,fig4         
#g4--;,hodge type window trap4 ,at left1
 trap with end  removed to show         
construction2 at right1 cross section of
 trap placed in  a window4 ,a1 ,end of  
trap4 ,b1 ,upper side of folds in       
screen4 ,c1  ,lower side of folds in    
screen4 ,d1 ,portion of end of trap     
sawed out and  returned after attaching 
screen4 ,e1 ,holes along apex of folds4 
,f1 ,door  for removing dead flies4 ,g1 
,window sill4 ,h1 ,upper window sash4   
,i1  ,inside entrance for flies4 ,o1    
,outside entrances4    ,this trap is    
essentially a screen box closely fitted 
to the frame of a  window 7see fig4 #g74
 ,the thickness of the box at ,a should 
be about #ab  inches4 ,instead of the   
screen running straight down over the   
box on either  side it is folded inward 
nearly to the center of the frame in    

,v-shaped  folds running longitudinally 
across the window4 ,one1 two1 or even   
more  folds may be made in the screen on
 either side4 ,the upper side of the    
fold  ,b should extend toward the center
 almost at right angles with the side   
of the trap--that is1 parallel with the 
top and bottom2 and the lower side  ,c  
should slant downward as shown in the   
drawing4 ,the sides of the frame  may be
 cut out at the proper angle and the    
pieces ,d returned after the  screen has
 been tacked along the edges4 ,along the
 apex 7inner edge7 of  each fold is     
punched a series of holes ,e about      
one-half inch in diameter  and #a inch  
apart4 ,the apices of the folds on      
either side of the window  should not be
 directly opposite4 ,a narrow door ,f   
opening downward on  hinges should be   
made on one side of the trap at the     
bottom for removal of  the dead flies4  
,the entire trap is fastened to the     
window by hooks so that  it may be      
readily taken off4 ,an additional       

trapping feature may be added  by       
providing a tent trap fitted in the     
bottom of the box4 ,a narrow slit is    
left along the base to allow the flies  
to enter beneath the tent4 ,bait  may be
 placed under the tent to attract the   
flies4    ,it has been found that the   
use of these window traps will aid in   
protecting animals in barns from stable 
flies and mosquitoes1 and in  some cases
 horseflies and other noxious species   
are caught4 ,they tend to  exclude the  
light1 however1 and are somewhat        
cumbersome1 especially in  thin-walled  
buildings4          ,,trapping ,,the    
,,screw-,,worm ,,fly4#e    #e           
,chrysomyia macellaria ,fab4            
,recent efforts to reduce the loss to   
the live-stock industry of the          
,southwest resulting from the ravages of
 the screw-worm have directed  attention
 to the employment of flytraps in this  
work4    ,mention has been made of the  
importance of preventing the breeding of
  flies as a prerequisite to effective  

control4 ,this is equally true of the   
screw-worm and other blowflies1 which   
attack animals1 and of the house  fly4  
,in the case of these blowflies main    
dependence must be placed on the        
complete and prompt burning of all      
carcasses and animal refuse4            
,experiments conducted in the range     
sections of ,texas indicate that traps  
properly baited and set are of material 
aid in preventing screw-worm  injury to 
live stock4 ,it is advised that at least
 one trap be maintained  on each section
 of land4 ,these should be located      
preferably near watering  places and    
where cattle congregate1 especially in  
the so-called hospital  traps1 where the
 screw-worm-infested animals are kept   
for treatment4    ,the conical-type     
traps as described are advised4 ,the    
traps should be set  on a board platform
 about #b feet square1 securely fastened
 to a tree or  on a post where the trap 
and bait will be the least disturbed by 
stock or  wild animals4    ,during the  

latter half of one season over #ajj     
gallons of flies1 the vast  majority of 
which were screw-worm flies1 were       
captured in about #be traps  operated on
 a ranch in west ,texas4    ,the        
question of the baits best adapted for  
this species and other points  in regard
 to the operation of the traps are      
briefly discussed under  subsequent     
headings4          ,,baits ,,for        
,,traps4      ,the problem of selecting 
the best bait for flies is an important 
one4  ,in choosing a bait it should be  
remembered that it is largely the       
fermentation which renders the material 
attractive1 and that baits are  most    
attractive during their most active     
period of fermentation4 ,as has  been   
indicated1 the kind of bait used should 
be governed by the species of  flies the
 destruction of which is desired4 ,this 
is most often the house  fly4           
,experiments conducted indicate that a  
mixture of cheap cane molasses          
7black-strap7 and water is among the    

most economical and effective baits  for
 the house fly4 ,one part of molasses is
 mixed with three parts of  water4 ,the 
attractiveness becomes marked on the    
second or third day4    ,sugar-beet or  
stock molasses1 which is very cheap1    
especially in regions  where produced1  
when mixed in the foregoing proportions1
 is fairly  attractive4    ,on dairy    
farms1 probably milk is the next choice 
as a bait to  cane-molasses solution1   
considering its convenience4 ,the curd  
from milk1  with about one-half pound of
 brown sugar added to each pound and    
water  to make it thoroughly moist1 is a
 very good bait and continues to be     
attractive for #aj days or more if kept 
moist4 ,a mash of bran made quite  thin 
with a mixture of equal parts of water  
and milk and with a few  tablespoonfuls 
of brown sugar and cornstarch and a     
yeast cake added makes  an attractive   
and lasting bait4 ,during hot weather   
stirring the old bait  or adding fresh  
is a daily necessity if best results are

 to be secured4    ,sirup made by       
dissolving #a part of ordinary brown    
sugar in #d parts  of water and allowing
 the mixture to stand a day or two to   
induce  fermentation is almost equal to 
the molasses and water as a fly bait4   
,if  it is desirable to use the sirup   
immediately after making it1 a small    
amount of vinegar should be added4      
,honeybees are sometimes caught in      
large numbers at this bait4 ,when this  
happens some of the other baits         
recommended should be used4    ,with the
 baits before mentioned comparatively   
few blowflies will be  caught4 ,for use 
about slaughterhouses1 butcher shops1   
and other places  where blowflies are   
troublesome1 it has been determined that
 the mucous  membranes which form the   
lining of the intestines of cattle or   
hogs are  without equal as a bait4 ,this
 material1 which is commonly spoken of  
as  gut slime1 can be obtained from     
packing houses where sausage casings are
  prepared4 ,the offensive odor of this 

bait renders its use undesirable very   
near habitations or materials intended  
for human consumption4    ,for use under
 range conditions experiments are       
underway with dried gut  slime4 ,this   
material is giving satisfaction as a    
screw-worm fly attractant  and is easily
 carried1 being in a highly concentrated
 form4 ,the flaky  material is placed in
 the bait pans and water added at the   
rate of #a part  slime to #aj or #bj    
parts water1 after which the mixture is 
thoroughly  stirred4    ,another        
packing-house product known as blood    
tankage is a good fly bait  when used   
with molasses and water4 ,this          
combination results in the capture  of a
 large percentage of house flies4 ,where
 these materials are not  obtainable    
fairly good catches will result from the
 use of fish scraps  or meat scraps4    
,with any of these baits the catches    
will be found not to  be entirely       
meat-infesting flies1 as actual counts  
have shown that the  percentage of house

 flies in traps over such baits ranges  
from #de to #ge4    ,overripe or        
fermenting fruit1 such as watermelon    
rinds or crushed  bananas1 placed in the
 bait pans sometimes gives satisfactory 
results4  ,a combination of overripe    
bananas with milk is much more          
attractive than  either one used        
separately4 ,a considerable number of   
blowflies as well as  house flies are   
attracted to such baits4          ,,bait
 ,,containers4      ,the size of the    
bait container in relation to the size  
of the trap is  a very important        
consideration4 ,it has been found that a
 small pan  or deep pan of bait set in  
the center under a trap will catch only 
a  small fraction of the number of flies
 secured by using larger1 shallow       
containers4 ,the best and most          
convenient pan for baits is a shallow   
circular tin1 such as the cover of a    
lard bucket4 ,under range conditions  it
 is advisable to use a more substantial 
bait pan and preferably one #a  inches  

deep1 so that a greater amount of bait  
may be used1 thus preventing  complete  
drying out between visits to the trap4  
,its diameter should be  about #d inches
 less than that of the base of the trap1
 thus bringing the  edge within #b      
inches of the outside edge of the trap4 
,for liquid baits  the catch can be     
increased slightly by placing a piece of
 sponge or a few  chips in the center of
 the bait pan to provide additional     
surface upon  which the flies may       
alight4 ,the same kind of pans for bait 
may be used  under tent traps4 ,two or  
more pans should be used1 according to  
the length  of the trap4          ,,care
 ,,and ,,location ,,of ,,traps4      ,in
 many cases flytrapping has been        
rendered ineffectual by the fact that   
the traps were not properly cared for4  
,in setting traps a location should  be 
chosen where flies naturally congregate4
 ,this is usually on the sunny  side of 
a building out of the wind4 ,it is      
exceedingly important that the  bait    

containers be kept well filled4 ,this   
usually requires attention  every other 
day4 ,the bait pans should be washed out
 at rather frequent  intervals4 ,this   
gives a larger catch and avoids the     
danger of flies  breeding in the        
material used for bait4 ,further1 it    
should be borne in  mind that traps can 
not be operated successfully throughout 
the season  without emptying them4      
,where flies are abundant and the bait  
pans are  properly attended to the traps
 should be emptied at weekly intervals4 
,where flies become piled high against  
the side of the cone the catching  power
 of the trap is considerably reduced4   
,the destruction of the flies  is best  
accomplished by immersing the trap in   
hot water or1 still better1  where a    
tight barrel is at hand place a few live
 coals in a pan on the  ground1 scatter 
two tablespoonfuls of sulphur over them1
 place the trap  over the coals1 and    
turn the barrel over the trap4 ,all of  
the flies will  be rendered motionless  

in about five minutes4 ,they may then be
 killed  by using hot water1 throwing   
them into a fire1 or burying them4 ,in  
the  operation of flytraps in           
controlling the screw-worm it has not   
been found  necessary1 especially during
 hot weather1 to kill the flies1 as they
 die  very rapidly within the traps4 ,in
 order to empty a trap it may be        
inverted  and the dead flies shaken     
down4 ,as the living flies will         
naturally go  upward1 the door may then 
be removed and the dead flies shaken    
out1 the  door replaced1 and the trap   
set upright without loss of many of the 
living  flies4          ,,sticky ,,fly  
,,papers4      ,sticky fly papers are of
 some value in destroying flies which   
have  gained access to houses1 but they 
have marked limitations and numerous    
objectionable features4 ,for use out of 
doors traps are much more effective  and
 economical4    ,dr4 ,crumbine1 of the  
,kansas ,state ,board of ,health1 gives 
the following  method for preparing fly 

paper3    ,take #b pounds of rosin and  
#a pint of castor oil1 heat together    
until it  looks like molasses4 ,take an 
ordinary paint brush and smear while hot
 on  any kind of paper--an old newspaper
 is good--and place several about the   
room4 ,a dozen of these may be made at a
 cost of #a cent4          ,,poisoned   
,,baits4      ,the question of          
destruction of flies with poisons is    
somewhat out of place  here1 but the    
close relationship of poisoned baits to 
trapping warrants a  brief statement4   
,probably the best poisoned bait for    
house flies is formaldehyde in milk     
used at the rate of about two           
teaspoonfuls of formaldehyde to a pint  
of a  mixture of equal parts of milk and
 water4 ,this is placed in flat dishes  
in places frequented by flies4 ,a piece 
of bread or a sponge in the dish  adds  
to the effectiveness4 ,brown sugar or   
molasses and water with #b per  cent    
formaldehyde 7commercial1 #dj per cent  
solution7 added will probably  also give

 satisfactory results4 ,as far as       
possible other liquids should be        
removed when poisoned baits are exposed4
    ,the use of poison solutions1       
especially arsenical solution in tubs   
containing portions of animal carcasses1
 has been tried and advocated  against  
the screw-worm by a number of stockmen4 
,a comparatively weak  poison           
solution--about #a gallon of dip1       
diluted for use on cattle1 to #g        
gallons of water--is sufficient4 ,best  
results usually have been secured  where
 a considerable portion of the animal   
matter was allowed to protrude  from the
 poison solution1 as there is a tendency
 for the solution  to harden the bait   
and prevent its decomposition1 thus     
reducing its  attraction for flies4     
,,caution4    ,it should be borne in    
mind that formaldehyde1 #dj per cent1 is
 poison  about in the same proportion as
 wood alcohol1 if taken internally4 ,it 
should not be inhaled1 nor should the   
eyes be unduly exposed to it4  ,special 

pains should be taken to prevent        
children from drinking poisoned  baits  
and to prevent the poisoned flies from  
dropping into foods or  drinks4         
,arsenical solutions1 as is well known1 
are extremely poisonous to  man and     
animals4 ,care should be taken to       
protect the poisoned baits from  lire   
stock and it is not advisable to have   
the baits close to barnyards  where     
fowls are kept1 as they may be poisoned 
by eating the dead flies4             99
       99       99       99       99    
,transcriber ,note    ,minor typos have 
been corrected4 ,illustrations were     
moved to prevent  splitting paragraphs4 
,produced from files generously made    
available by  ,,usda through ,the       
,internet ,archive4 ,all resultant      
materials are placed in  the ,public    
,domain4