Common differential locust or grasshopper; a, egg nests underground; b, young nymph; c, d, older nymphs; e, adult grasshopper; f, nymph feeding on grass. This shows development with incomplete metamorphosis.
In the same order with the grasshoppers come the crickets, katydids, rear-horses, devil's darning-needles or walking-sticks, and cockroaches. The grasshoppers are most troublesome, however. They deposit eggs in the ground and in other protected places. In the spring these hatch into young "hoppers" scarcely larger than a pin head at first. Throughout the early summer these small fellows feed and increase in size. They burst their old skins and crawl out of them a number of times as they grow larger. Toward fall they become full grown with four strong wings and very powerful hind legs for jumping. In this condition most of the common grasshoppers will be found in the fall when the rural schools open.
The small so-called red-legged grasshopper is always most abundant in the fall and for this reason we have selected it for our studies. It is aboutan inch long, olive-brown in color with the ends of the hind legs bright red. It is found everywhere in pastures, meadows and along country roads. Approach one of them in the field and see what happens. How does it get away? When disturbed, how far does it go? Does it hide in the grass when you try to catch it? Observe one that has not been disturbed. Where do you find it; on the ground or on plants? How does it move about when not scared? Watch carefully and see what plants it feeds on. How does it go about it? What do you find feeding on grasshoppers? How does a turkey catch them? Have you ever seen a dull colored fly, which inhabits dry paths and which flies with a humming sound like a bee, feeding on grasshoppers? These are called "robber-flies" or "spider-hawks" and they destroy thousands of grasshoppers.
After you have learned all you can about the habits of the grasshopper in the field, catch a few of them and take them home and put them in a glass fruit jar. Collect green leaves for them and watch them feed. Watch their method of feeding closely and see how it differs from that of a horse or a cow. How do they move about in the jar? Which legs are used in walking? What do they do with the jumping legs while walking? Do they use their wings at all while in the jar? Watch them wash their face and feet after feeding. Give them leaves of different plants, especially of field and garden crops and determine which they like best. Can you find any plant which they will not eat? Find out how fast they feed and considering the life of any one individual to be 200 days, calculate the number of grass blades each individual may eat. Are the feelers used while in the jar, and if so for what purpose?
Take a grasshopper from the jar and examine it carefully. Count the number of legs, wings and joints in the body. How many joints in the legs? Examine the tip of the foot for a soft pad and on either side of it a strong hook. What are these used for? What are the sharp spines on the side of the hind-legs for? Examine the side of the body and see if you can find the small breathing pores. How do the legs join the body? Where are the wings attached? How broad are the wings as compared with the body? How are they folded? Are the two pairs of wings alike? Which is used most in flying? Is the head firmly attached to the body? Examine the large eyes; where are they found? Will grasshoppers bite you while handling them? What is the brown juice which escapes from the mouth when disturbed? How long are the feelers as compared with the body? Can you tell the males from the females?What is the distinction? Do they ever make music? Examine for all the foregoing points and write a brief report covering these. Make a careful drawing of a grasshopper from one side; also make an enlarged drawing of the face of a grasshopper and name the parts.
Inthe house fly we find one of man's most deadly foes. War can not compare with the campaigns of disease and death waged by this most filthy of all insects. In our recent strife with Spain we lost a few lives in battle, but we lost many more in hospitals due to contagious diseases, in the transmission of which this pest played a most important part.
The fly is dangerous on account of its filthy habits. It breeds in filth, feeds on filth in open closets, slop-barrels, on the streets and in back alleys and then comes into the house and wipes this germ-laden filth on our food or on the hands or even in the mouths of helpless babies. Who has not seen flies feeding on running sores on animals,or on "spit" on sidewalks? These same flies the next minute may be feeding on fruits or other food materials. We rebel when pests destroy our crops or attack our stock, but here we have a pest which endangers our very lives, and the lives of those dear to us.
House fly; a, larva or maggot; b, pupa; c, adult; e, egg. All enlarged. (Modified from Howard Bur. of Entomology. U. S. Dept. Agri.)
If the fly confined itself to filth we could overlook it as it would help to hasten the removal of filth. On the other hand, if it avoided filth and remained in our home we could not overlook it, but we could feel safe that it was not apt to do us a great deal of harm. But, like the English sparrow, one minute it is here and the next somewhere else; from filth to foods and then back again to filth. In this way it carries disease germs upon its feet and other parts of its body and by coming in contact with food material some of these germs are sure to be left on it and cause trouble later. The fly's method of carrying disease is different from that of the mosquito where the germ is carried inside its body.
Favorite breeding places of house fly. Such places should be kept as clean and neat as the front yard.
The presence of flies in the home is usually a sign of untidiness; but it means more, it means that disease and often death is hovering over the home. We are too apt to consider the fly simply as a nuisance when we should take it more seriously. The child should be led to realize that the fly should not be tolerated in the home, that it is dangerous and that it can and must be destroyed.
An open closet to which the house fly has free access. Such a closet is the most dangerous accessory of any home.
The house fly may pass the winter either as the adult fly in cracks and crannies about the home, or in out-buildingsor it may remain as a hard, brown, oval pupa in stables and manure piles when, with the first warm days of spring, it escape from this case as the fly ready to lay eggs for the first colony. The fly breeds largely in horse manure either in stables, manure piles or in street gutters where manure is allowed to collect. Each female lays a large number of eggs and since it requires less than two weeks for the pest to mature, we are soon overrun with flies in the summer where steps are not taken to control them. The maggots are often so abundant in stablesthat they can be scooped out with a shovel. This ceaseless breeding continues from spring until the first frost in the fall.
In the control of the fly and prevention of trouble from it there are three important steps to take. First of all, go to the source of the trouble and do away with or screen all breeding places. Then, by keeping in mind the fact that the fly is comparatively harmless as long as it is kept from filth laden with germs, do away with all open closets, uncovered slop-barrels and other filth. As a further precaution keep it from the home by the use of screens and when necessary "swatters." Do not make the mistake of trying to control the pest with the "swatters" alone. In the country too often manure is permitted to accumulate about the barn during the summer with a view of using it on wheat ground in the fall and this furnishes ideal conditions for the fly to breed. Another source of constant danger especiallyin the rural districts is the presence of open closets or worse still the presence of no closet at all. This is without doubt the most dangerous accessory of the farm. More screens should be used in the home and greater care in keeping them closed.
Observe first of all the feeding habits of the fly. What foods in the home is it most fond of? Make a list of allthe food materials it is found to feed on. Where and on what is it found feeding out doors? Do you find it feeding on filth and if so, on what? Do you find it about the barn? Where is it usually found in the barn? How can the fly carry filth to food materials?
In studying the breeding of the fly determine where it lays its eggs and where the maggots are found. Examine fresh manure in the stable and see if you can find small white maggots about half an inch long and as large around as the lead in a pencil. If you do, place some of them with some fresh manure in a glass jar and see what becomes of them. In a few days the maggots will disappear and in their places small oval, brown bean-like objects will appear. A few days later these will crack open at one end and the fly will crawl out. Keep records of the length of time it requires for the pest to pass from one stage to the other. If maggots cannot be gottenput some fresh manure in the jar and catch a number of live house flies and put them in with the manure and watch for results. Collect a jar of fresh manure with maggots and sift over it a little powdered borax and see what happens to the maggots. Where horse manure can not be properly disposed of, cheap borax is used to throw over piles of manure to destroy the maggots and prevent the flies from breeding in it. Write a brief description of the different stages and make careful drawings of these. Do not mistake the house fly for other flies often found on food in the home.
Collect a few flies and put them in a bottle and drop in with them just a few crumbs of sugar and watch them feed. They cannot chew but a little saliva from the mouth dissolves a little of the sugar which is then lapped up as syrup. Notice what a peculiar sucker they have for drawing up liquids. How can they crawl along in the bottle with their backs toward the floor?Examine the tip of their feet for a small glue pad which sticks to the glass. These glue pads and the sucker are well fitted for carrying filth. Examine the fly carefully and write a brief description of it. What color is it? How many legs? How many wings? Are these transparent? Behind the wings there is a pair of small stubs which is all that is left of the hind pair of wings. Are the eyes large? Can you find a pair of small feelers? Why can you not pick up a fly like you would a grasshopper? Is their eye sight good? Why are they always most abundant on a kitchen screen door? Can they smell?
What are the fly's worst enemies? Will the toad eat them? Do chickens eat them? Have you ever seen chickens scratching in manure and feeding on the fly maggots? Put a few drops of formaldehyde, which you can get from a druggist, in a few spoonfuls of sweet milk or sugar syrup and let the flies eat it and see what happens tothem. This is one of our best poison baits for flies which get in the home or collect about the dairy. Formaldehyde is a poison and when used in bait it must be kept out of reach of children. Just about frost, in the fall, watch for the appearance of inactive flies on walls, windows and other parts of the house. These have been attacked by a parasitic disease. These are often found sticking to walls and other objects about the room in the winter, and are commonly thought to be passing the winter.
"The insect we now call the 'house fly' should in the future be termed the 'typhoid fly,' in order to call direct attention to the danger of allowing it to continue to breed unchecked."—L. O. Howard.
"The insect we now call the 'house fly' should in the future be termed the 'typhoid fly,' in order to call direct attention to the danger of allowing it to continue to breed unchecked."
—L. O. Howard.
Herewe have another small insect which, like the house fly, is extremely dangerous, due to its ability to carry the germs of disease. There are hundreds of species of mosquitoes, some small, some large. The majority of these are unable to carry disease so far as we know at present, but they should be avoided as dangerous. The Missouri forms which carry disease are the so-called malarial fever mosquitoes, and they are entirely responsible for the transmission of this sapping and often fatal disease. In the warm countries these are more abundant and the fever is more fatal. In the south there is still another disease-carrying mosquito, the yellow fever mosquito. This form is most dangerous of all.
The mosquito first bites a patient suffering with malaria and in this way it takes in germs along with the blood which it sucks from the patient. After these germs pass through stages of development in the body of the mosquito they are ready to be injected back into a healthy person where, in due time, they cause the disease. The germs feed inside the red blood corpuscles and at regular intervals they destroy a large number of these causing a chill which is followed by fever and a new supply of corpuscles is produced. This alternation of chill and fever may continue all summer, if medicine is not taken to destroy the germs. Quinine will kill the germs if it is taken so that plenty of it is in the blood when the germs come out of the torn down corpuscles during a chill.
In order to prevent malarial fever, get rid of the mosquitoes by draining and oiling the breeding places, escape their bites by screening houses, smudging and destroying the adults, and keepthe mosquitoes from patients who have the fever. This is almost as important as the destruction of the mosquitoes. The malarial fever mosquitoes are as harmless as our common forms so long as they do not become infected with germs by sucking blood from a fever patient.
Mosquitoes in position for biting; a, common Culex mosquito; b, malarial fever mosquito. Note that the one stands parallel, while the other stands at an angle to the surface on which it rests.
In view of the fact that most of our common mosquitoes are classed as non-dangerous, it is of interest to know just how to distinguish the harmless ones from the dangerous. The adults of the two forms can be easily distinguished when they are seen at rest. The common forms always rest with the body parallel to the surface on which they rest, while the malarial form alwayselevates the end of the body so that the head is pointed toward the surface on which it rests. In like manner the wigglers can be distinguished from each other. Our common wigglers always hang head downward in the water while those of the malarial mosquitoes rest near the surface of the water with their bodies parallel to it. The majority of the wigglers found in rain barrels are of our common forms.
Common Culex mosquito showing stages of development; a, raft of eggs; b, larvæ or wigglers of different sizes; c, pupa; d, mosquito. The large wiggler and the pupa are taking air from the surface of the water through their breathing tubes.
The life of the mosquito is quite interesting and is an excellent example of an insect which lives in the water part of its life and in the air the rest.The mature female mosquito, which does all the biting, searches for water in rain barrels, cans, ditches, ponds, and stagnant swamps where she lays her eggs either in raft-shaped packets or singly. When the wigglers hatch they swim about in the water and feed upon decaying material and microscopic water plants. When the wiggler is full grown it changes to an active pupa which has a large head and a slender tail and is more or less coiled. A little later the winged mosquito escapes. In the rural districts most of the mosquitoes breed in stagnant ponds, swamps and rain barrels and from these they fly to the home where they cause trouble. Such places should be drained or protected with oil or other means to prevent the mosquito from using them for breeding purposes. Ponds can be freed of the wigglers by introducing fish or by using a small amount of coal oil on the surface. The wigglers have a breathing tube which is thrust out above thewater when fresh air is needed and if there is a thin film of oil on the water this is prevented. Rain barrels can be freed of the pest in this way also, or perhaps better by covering them with a cloth. The mosquitoes are most troublesome about the home at night. When one sits out doors he should keep a smudge going to drive them away while screens will keep them out of the house at night.
Collect all the different kinds of mosquitoes you can find and note difference in size and markings. Do you find the malarial fever mosquito in your region? Is malarial fever common during the summer and fall? Are there any old stagnant ponds or swamps near your home? If so, examine these for wigglers. Examine rain barrels for small raft-shaped packets of eggs. These resemble small flakes of soot and are difficult to pick up between your fingers. Take a stickand lift them from the water and examine them. One packet may contain a hundred or more eggs. Put a few of these packets in a tumbler of rain water and watch for the wigglers. At first they will be very small but they grow fast. Watch them come to the surface to breathe. The tip of the tail is projected above the water and air is taken in at two small breathing pores or spiracles. Examine rain barrels for the larger wigglers. What do they live on in the rain barrel? What do they do when you jar the barrel? Do you find any of the rounded pupae in the barrel? They are active the same as the wigglers. If you find pupae, put some in a tumbler of water, cover it with cloth or a lid and watch for the mosquitoes to appear. After collecting several mosquitoes examine them for number of wings, legs and markings and see if all have the slender sucking tube. The males have large feathery feelers, but no sucking tube.
Write a brief description of the wigglerand the mosquito, their breeding places and means of destroying them. Make drawings of the different stages, wiggler, pupa and mosquito.
"And here and yonder a flaky butterflyWas doubting in the air."
"And here and yonder a flaky butterflyWas doubting in the air."
"And here and yonder a flaky butterflyWas doubting in the air."
—McDonald.
Egg of cabbage miller much enlarged.
Withthe first approach of spring comes swarms of large green flies which bask in the March sun on the south sides of buildings. They are not with us long, however, until we notice flashes of white quickly moving about from one early weed to another. These are the advance guards of the cabbage millers or butterflies. All through the cold winter they remained in the chrysalis stage stuck to the sides of houses, fence posts and in other protected places, awaiting the first breath of spring. The first adults to emerge find no cabbage on which tolay their eggs so they are compelled to use other plants such as pepper grass.
The eggs are very small and are usually placed on the lower edge of the leaf. These hatch and the small green worms appear. Throughout the summer there are a number of broods produced and an enormous amount of damage is done. Just before frost the last caterpillars search for protected places where they pass to the pupal or resting stage for the winter. No cocoon is spun by this caterpillar.
Where measures are not taken to control the cabbage worms they destroymuch of the cabbage crop each season. The white butterflies can be seen any day during the summer visiting cabbage, mustard, radishes and other similar plants. By destroying all of the worms and millers in the early spring one has less trouble later. This can be done by hand picking, or where the patch is large by spraying with a poison solution to which soap is added to keep the solution from rolling off in large drops. Poison can be used until the heads are well formed, but if the first worms in the spring are destroyed, later spraying is unnecessary though an occasional handpicking will help.
Cabbage worm feeding, slightly enlarged.
Pupa or chrysalis of cabbage miller.
Go into the garden and examine the cabbage for small green worms which vary from one fourth to a little over an inch in length. What is the nature of their work on the leaf? Where do they feed most, on the outer or inner leaves? Do they eat the entire leaf?How does the work of the young worms differ from that of the larger ones? Do they spin silk? Are they on the top or under side of the leaf? Examine under the dead and dried leaves at the ground and see if you can find small, hard, gray objects which have sharp angles and which are tied to the leaf with a cord of silk. What are these objects? Watch the miller as she visits the cabbage and see if youcan find the small eggs which she lays on the under side of the leaves. When she visits a cabbage plant she bends her body up under the outer leaves and stops but a moment, fluttering all the while as she sticks the small egg to the leaf. It is about the size of a small crumb of bread. What does the miller feed on? Does she visit flowers? If so, what flowers?
Collect a few of the worms and put them in a glass jar with a piece of cabbage leaf. Examine them carefully and watch them crawl. How many legs do they have? Where are they placed on the body? How can they use so many legs while crawling? How many joints are there to the body? Note the short fine hair allover the body which gives it the appearance of green velvet. What color is the head? How does the caterpillar feed? Write a brief description of the worm. Do not mistake it for the cabbage span-worm which is also green, but which walks by humping up its back.
Cabbage miller on red clover blossom.
Keep the cabbage worms in the jar for a few days and watch them disappear. After they have disappeared, what is left in the jar? These are the chrysalids or pupae of the insect and later from them will come the millers.Take one of the pupae in your hand and see if it can move. If it is in the summer the miller will appear in a week, but if it is in the late fall it will simply pass the winter in the pupa stage. Watch the miller escape from the pupal case and describe it. Examine the miller carefully and describe briefly the number of legs, wings, segments of body, sucking tube and color markings. Make careful drawings of the caterpillar, chrysalis and butterfly. What gives the color to the wings? Rub the wings between your fingers and see if the color comes off. The wings are covered with very small scales of different colors which combine to give the beautiful markings. The wings of all butterflies and moths are covered with scales and hairs in this way. In this insect we find both chewing and sucking mouth parts. The caterpillar chews while the parent butterfly has a long tube for sucking up nectar from flowers and water from puddles in the road.
"Far out at sea—the sun was high,While veered the wind and flapped the sail;We saw a snow-white butterflyDancing before the fitful galeFar out at sea."The little wanderer, who had lostHis way, of danger nothing knew;Settled a while upon the mast;Then fluttered o'er the waters blueFar out at sea."Above, there gleamed the boundless sky;Beneath, the boundless ocean sheen;Between them danced the butterfly,The spirit-life of this vast scene,Far out at sea."The tiny soul that soared away,Seeking the clouds on fragile wings,Lured by the brighter, purer rayWhich hope's ecstatic morning brings—Far out at sea."Away he sped, with shimmering glee,Scarce seen, now lost, yet onward borne!Night comes with wind and rain, and heNo more will dance before the morn,Far out at sea."He dies, unlike his mates, I weenPerhaps not sooner or worse crossed;And he hath felt and known and seenA larger life and hope, though lostFar out at sea."
"Far out at sea—the sun was high,While veered the wind and flapped the sail;We saw a snow-white butterflyDancing before the fitful galeFar out at sea."The little wanderer, who had lostHis way, of danger nothing knew;Settled a while upon the mast;Then fluttered o'er the waters blueFar out at sea."Above, there gleamed the boundless sky;Beneath, the boundless ocean sheen;Between them danced the butterfly,The spirit-life of this vast scene,Far out at sea."The tiny soul that soared away,Seeking the clouds on fragile wings,Lured by the brighter, purer rayWhich hope's ecstatic morning brings—Far out at sea."Away he sped, with shimmering glee,Scarce seen, now lost, yet onward borne!Night comes with wind and rain, and heNo more will dance before the morn,Far out at sea."He dies, unlike his mates, I weenPerhaps not sooner or worse crossed;And he hath felt and known and seenA larger life and hope, though lostFar out at sea."
"Far out at sea—the sun was high,While veered the wind and flapped the sail;We saw a snow-white butterflyDancing before the fitful galeFar out at sea.
"The little wanderer, who had lostHis way, of danger nothing knew;Settled a while upon the mast;Then fluttered o'er the waters blueFar out at sea.
"Above, there gleamed the boundless sky;Beneath, the boundless ocean sheen;Between them danced the butterfly,The spirit-life of this vast scene,Far out at sea.
"The tiny soul that soared away,Seeking the clouds on fragile wings,Lured by the brighter, purer rayWhich hope's ecstatic morning brings—Far out at sea.
"Away he sped, with shimmering glee,Scarce seen, now lost, yet onward borne!Night comes with wind and rain, and heNo more will dance before the morn,Far out at sea.
"He dies, unlike his mates, I weenPerhaps not sooner or worse crossed;And he hath felt and known and seenA larger life and hope, though lostFar out at sea."
—R. H. Horne.
Apple worms in core of apple. Usually only one worm appears in an apple. Note the decaying of the apple.
Thisis perhaps the most destructive insect pest attacking the apple. Every year, that we have a good apple crop, there are thousands of bushels of wormy apples which are practically worthless. This means an actual loss of thousands of dollars a year to theapple growers of this country. For this reason alone each child should come to know the life history, habits and injury of this pest. It is most destructive to the apple though the pear comes in for its share.
The codling moth slightly enlarged. (From Slingerland).
Every country child and many of those of the cities, are familiar with this worm for they often bite into it while eating apples. The small worms crawl down in the blossom end of the young developing apple and from there bore into the pulp and eventually reach the core of the fruit. They stay in the apple about six weeks when they eat a hole out to the surface and crawl down to the trunk where loose bark offers a hiding place. Here they spin their cocoons and change to a small,brown, plump pupa and after a few days the winged moth emerges. The moth is very small and is not often found by one not acquainted with it. They come out during late June and early July when they lay eggs for a second colony of worms which again enter the fruit and destroy more of it. These worms of the second brood are usually mature and leave the fruit about the time apples are picked in the fall in central Missouri. They escape and soon spin cocoons in which they pass the winter. Early in the spring these change to pupae and later the moths come out. They appear about the time apples bloom in the spring and lay the eggs for the first worms which enter in great numbers at the blossom end.
Apple blossoms at about the right stage for receiving the first and most important arsenical spray for the control of the apple worm.
This in short, is the life story of the pest through the year. Little can be done to destroy the pest after it gets into the fruit, therefore remedies must be applied to destroy the worm before it gets into the fruit. All orchardsshould be sprayed with a poison in the spring before the worms appear. Since most of them enter by way of the blossom end, it is necessary that the poison be put into the blossom end. To do this spray at once after the blossoms fall, repeat after two weeks and spray again in July to kill the second brood of worms. The protection of woodpeckers and sapsuckers will alsohelp as they feed on the worms under the bark.
Go into the orchard and examine for apples with masses of sawdust-like material projecting from the sides or blossom end. By removing this brown deposit which is the excrement of the worm, you will find a hole leading into the apple. Cut open one of these and determine the course of the tunnel. Where do you find the worm? Do all such apples contain worms? Where have they gone? How does the feeding of the worms injure the fruit? Do any of the wormy apples show rot? Are any of the windfalls in the orchard wormy and if so what proportion?
Remove a worm from one of the apples and examine it. How many legs has it? What color is it and does it have hair upon its body? Can it crawl fast? Does it spin silk? Put a number of the large worms in a jar and examine from day to day and keep records of what happens. Collect anumber in the fall and keep them in a box outdoors during the winter. In the spring watch them change to the pupa in the cocoon and a little later the mature insect or codling moth, as it is commonly called, will emerge. Describe the moth and pin a number of them for your collection. What time in the spring do the caterpillars change to the pupa and when do the moths emerge? If you keep the moths in a bottle they will lay their small circular flat eggs where they can be seen by looking closely. During the winter examine under the bark of apple trees and in cracks and crevices about apple pens for the small silk cocoons containing the worms. Examine in the same places in the spring about apple blooming time and then in place of the small pink worms you will find the small brown pupae. Keep these a few days and the moths will appear.
What proportion of apples in your region are wormy? What are they used for? Are the trees sprayed justafter the blossoms fall to control the pest? Where spraying is carefully done, are there as many wormy apples? Why not spray all the orchards properly and have no worms?
Draw and describe the different stages of the apple worm or codling moth and its injury to fruit.
"O, yet we trust that somehow goodWill be the final goal of ill,To pangs of nature, sins of will,Defects of doubt and taints of blood;"That nothing walks with aimless feet;That not one life shall be destroyed,Or cast as rubbish to the void,When God hath made the pile complete;"That not a worm is cloven in vain,That not a moth with vain desire,Is shrivelled in a fruitless fire,Or but subserves another's gain."
"O, yet we trust that somehow goodWill be the final goal of ill,To pangs of nature, sins of will,Defects of doubt and taints of blood;"That nothing walks with aimless feet;That not one life shall be destroyed,Or cast as rubbish to the void,When God hath made the pile complete;"That not a worm is cloven in vain,That not a moth with vain desire,Is shrivelled in a fruitless fire,Or but subserves another's gain."
"O, yet we trust that somehow goodWill be the final goal of ill,To pangs of nature, sins of will,Defects of doubt and taints of blood;
"That nothing walks with aimless feet;That not one life shall be destroyed,Or cast as rubbish to the void,When God hath made the pile complete;
"That not a worm is cloven in vain,That not a moth with vain desire,Is shrivelled in a fruitless fire,Or but subserves another's gain."
—Tennyson.
Thisinsect is often very destructive to tomatoes and tobacco. Most country boys and girls know it and fear its ugly looking horn. When full grown it is four inches long, usually dark green with a number of slanting white lines along either side. It is so nearthe color of the plants that it is difficult to see it.
Egg of Tomato worm moth enlarged.
During the summer months the worms are common, being most abundant in August. In the fall the mature worms go into the ground and change from the worm to a large, oval, brown pupa with a jug-handle-like appendage on the under side. These are often turned up when the garden is plowed in the spring. After tomato plants are well started the large greyish humming-bird-like moths comes from the ground and begin laying eggs. The moth expands from four to six inches and is often seen at dusk visiting the blossoms of "jimson weed" and other large tube flowers. They are also found around lights at night.
Young tomato worm.
Where they are troublesome the plants should either be sprayed with a poison when the injury is first noticed or else the worms should be picked off and destroyed. There is a small parasitic wasp which is very helpful in destroying this caterpillar. They live inside the worm and when mature bore out through the skin on the sides and back where they spin small white egg-like cocoons from which later the small wasps emerge. Often a hundred or more may come out of one worm.
Observe the worms where they are at work on tomatoes. Disturb them and hear them grind their jaws together. Do they eat the foliage rapidly? Dust a little Paris green on the foliage where a worm is eating and see what happens in half an hour. Collect a number of the worms in a glass fruit can and give them tomato leaves to eat and watch them grow. How manysegments are there to the body? How many of the segments have small black spots on either side? These are holes through which the worm breathes. Is the horn at the end of the body stiff enough to stick into your hand? This is thought to be a sting but it is only an ornament and is entirely harmless. When full grown they will burrow intothe sand in the jar and change to the pupa.
Full-fed tomato worm slightly reduced.Chrysalis or pupa of tomato worm. Note the jug-handle-like sheaths enclosing the proboscis.
Full-fed tomato worm slightly reduced.
Chrysalis or pupa of tomato worm. Note the jug-handle-like sheaths enclosing the proboscis.
Examine the brown pupa carefully and see if it can move. What is the peculiar structure on the under side of the body? The moth which comes from this in the spring is very large. It is covered with white and black scales and hairs which give it a mottled appearance. Examine on the under side of the head for a peculiar structure like a watch spring. This is the sucking tube used in drawing up nectarfrom deep tubular blossoms. When the moths are sipping nectar from "jimson weed" blossoms they can be killed by pouring a little poison down into the blossoms.
Tomato worm moth natural size.
Thisinsect is of little economic importance to us at present but its peculiar habit of producing light makes it a very striking form and one which deserves study. The firefly is a beetle, and begins to make its appearance the latter part of June when the darkest nights may be one solid glow of fire. They live largely in damp places and bottoms at night are specked with their tiny flashes of light. The larval or grub stage is passed on the ground beneath grass, weeds and rubbish where they often prey upon other insects. In some cases the grubs may be able to produce light though as a rule the luminous grub-like creature or glow-worm is a wingless adult firefly.
Firefly beetles on sour-dock leaf.
Lower surface of firefly beetle enlarged to show the light producing segments of the abdomen.
Watch for the first appearance of the fireflies in the evening and see where they come from. Do they all appear at once or only a few at first? Do they fly fast? How often is the light produced? Will they produce the light while on the ground? When they fly do they stay near the ground or high in the air? Do they light in trees?
Catch one of the fireflies in your hat and examine it carefully. How largeis it? Describe briefly its size, shape and color. Are its wing covers hard like other beetles? Where is the light produced? What color is the light? Is it bright? Hold the firefly on the opposite side of a sheet of paper and see if the light will show through. Try the same with your hat, coat sleeve and other objects. This light is extremely penetrating and unlike the light of a lamp is produced with the generation of very little heat. Will it continue to flash while you hold it? Are the segments from which the light comes the same color as the other segments of the body? Crush the tip ofthe body between your thumb and finger and see if the light continues to appear. How long does it last? Collect a number of the fireflies and put them in a bottle and see if the light is strong enough to enable you to read.
The firefly has proven to us that our methods of producing light are extremely wasteful since much of the energy is lost in heat and it is possible that through the lesson of the firefly we may some day be able to produce better light at less expense.
White grub feeding on roots of corn plant, enlarged.
Thisinsect is more familiar to country children in the grub stage. Every one who has followed a plow in rich sod land has seen these fat, white coiled grubs roll down into the furrow when the plow turns them up. They are in the ground feeding on the roots of plants. Often all the roots ofgrass in lawns and meadows are eaten off and the sod dies and can be rolled up like strips of carpet. This insect breeds largely in sod and when this is plowed under and other crops are planted the grubs may injure them severely.Corn, wheat, oats and truck crops are severely injured. In some cases the grubs may feed for three years before they change to the pupa and later to the adult beetle. To control this pest, plow in the fall and rotate crops, so that sod will not remain on the same land too long.