=DISEASES AND ENEMIES OF BEES.=
DIARRHEA AND DYSENTERY.
In the chapter on wintering bees allusion has been made to certain
conditions which bring about diarrhea in bees. Not only will soured or
fermented honey produce this disease, but thin honey also, by requiring
too great exertion on the part of the bees to get rid of the surplus
moisture taken into their bodies, may indirectly cause the disease.
Repeated complaints have been made by those located near cider mills
that the apple juice collected by their bees was the cause of diarrhea
and dysentery. Aphidid secretions sometimes have the same effect.
Prolonged and intense cold in the interior of the hive, especially if
the stores are not of the best quality, causes distention and resulting
weakness and soiling of the hive and combs. Dampness and chilling of
individual bees frequently cause it. The effort some make to avoid the
dampness often results in the chilling, for the cover is removed, and
also some portion of the packing or the quilt or honey board to let the
air pass through to dry the interior. The true remedy is a cleansing
flight and warmth in the hive. Should the weather not be favorable
for this out of doors, the hive may be brought into a warm room and a
cage of wire cloth 2 or 3 feet square placed over the entrance. When
thoroughly warmed up the bees will fly in this and find their way back
into the hive. It is best to leave them in the warm room two or three
days, lowering the temperature gradually before returning the hive to
its outside stand.
FOUL BROOD.
This disease, being highly contagious, is dreaded most of all by the
bee keeper. It is due to the presence of minute vegetable organisms
in the body of the bee, the larva, or the egg, which prey upon its
tissues. These, as Prof. Frank Cheshire has shown, are bacilli, which,
multiplying with marvelous rapidity by division and also by spores,
are carried from hive to hive, until from a single infection the whole
apiary is soon ruined. The particular bacillus which is commonly known
as foul brood Professor Cheshire has described as _Bacillus alvei_,
or hive bacillus, as it affects not only the brood but also the adult
bees. (See Pl. XI.) The first symptoms noticeable in the hive are its
lack of energy, then dead larvæ turned black in the cells, and finally
sunken caps, some of them perforated slightly over larvæ and pupæ.
Bul. 1, new series, Div. of Entomology, U. S. Dept. of Agriculture.
Plate XI.
[Illustration]
Bacillus Alvei (Cheshire).
[Drawn from nature by Frank R. Cheshire for Jour. R. Micr. Soc., and
here reduced one-sixth from the original plate.]
Fig. 1.--Residue of larva three days dead of _bacillus alvei_;
_b_, bacilli. Spores and degenerated trachæ cover the field.
Fig. 2.--Healthy juices of bee larva.
Fig. 3.--Juices of larva (living) with disease in acute stage;
_a a_, leptothrix forms.
Fig. 4.--Brood cells from a diseased colony; _a a_, cells containing
healthy forms.
Fig. 5.--Cultivation in sterilized agar-agar showing the colony form of
bacillus.
Fig. 6.--Same cultivation twenty-four hours later.
Fig. 7.--Spore changing into bacilli.
Fig. 8.--Bacillus passing into spore condition.
All of these symptoms may, however, be present when no foul brood
exists; but if, upon opening some of the cells whose caps are sunken
or slightly punctured, a brown, ropy, putrid mass is found, which,
when lifted on the end of a sliver of wood, glides back into the cell
or strings down from the mass like thick sirup, it is pretty certain
that foul brood is present. Caution is necessary or it maybe spread
all through the apiary. The hands, as well as all tools used about
the infected colony, should be cleansed by washing in a solution of
corrosive sublimate (one-eighth ounce dissolved in 1 gallon water)
before going to another hive. If but few are found diseased they should
be burned at once--at night, when all the bees are at home. If all
or nearly all are affected, or if the disease does not seem virulent
and other apiaries in the neighborhood are not endangered thereby, a
cure may be attempted. Removal of all of the combs and confinement
of the bees in an empty box, obliging them to fast until some drop
from hunger, followed after releasing them by liberal feeding, will
frequently effect a cure, as indicated many years since by Mr. M.
Quinby. The hives may be disinfected by washing in carbolic-acid
water and used again. A second removal of the bees and fasting may
be necessary in some cases. It will also be well to feed medicated
sirup--1 part of carbolic acid, or phenol, to 600 or 700 parts of
sirup. Many omit the fasting, but destroy all combs and frames and
supply comb-foundation starters, removing four days later all combs
built and giving a second lot of starters. It is well to supplement
this treatment with feeding of medicated sirup. Phenol having been
suggested to Professor Cheshire as a remedy, he experimented until he
found that if a sirup containing 1 part of phenol to 400 or 500 parts
of the food be poured in the cells adjacent to the brood, and the
diseased brood, after brushing off the bees, sprayed with a solution of
1 phenol to 50 water, a cure was speedily effected. The great risk of
spreading the disease, as well as the time and expense which a cure by
drugs by the fasting process involves, will cause immediate destruction
to be resorted to as the cheapest in the end if taken in time.
_Bacillus gaytoni_, also described by Professor Cheshire, is
characterized by loss of hairy covering on the part of the workers and
their crawling out of the hives over the ground, constantly wriggling
their bodies until death occurs. It yields, according to Professor
Cheshire, to the same remedies as Bacillus alvei, but having been less
destructive and being far more likely to disappear without effort to
cure it, less attention has been given to it. Lately, however, it
has been alarmingly destructive in some of the extensive apiaries of
California. Colorado, and Texas, so that some simple remedy would be
very welcome.
THE WAX OR BEE MOTH.
The larva of a moth known to entomologists as _Galleria mellonella_
Linn. gnaws passages through the combs of the bees, especially those
in or near the brood nest, often proving very destructive in weak or
neglected colonies. The popular name, wax moth, was doubtless given
on the supposition that the food of the larva was chiefly wax; but
when an attempt to rear them on this substance in its usual commercial
purity is made slight development only results. Probably chemically
pure wax would not be touched by the larva; but in combs containing the
larval skins left by developing bees, or containing brood or pollen,
they reach their highest development if left undisturbed during warm
weather, finding ample nourishment in the nitrogen-containing pollen
and animal tissues left by the molting larvæ. To protect themselves
from the bees they line their galleries through the combs with a strong
web of silk and are able to retreat or advance rapidly through them
when attacked. The observing bee keeper will occasionally notice the
moths resting during the daytime on the corners of the hives or under
the roof projections or edges of the bottom boards. Its color is dull
or ashy gray, with light and dark streaks, making it so nearly like a
protruding sliver of a weather-beaten board as to protect it materially
from its enemies when resting on any unpainted surface that has been
long exposed. At nightfall the moths may be seen flitting about the
hive entrances, seeking an opportunity to enter and deposit their eggs.
If prevented by the bees, which are then instinctively on the alert,
they deposit in the crevices between the hive and stand or between the
hive and cap. The minute larvæ as they emerge soon make their way into
the interior of the hive. It is possible also that some of the eggs
of the moth may be left where the bees crawling over them carry them
into the hive by accident, the freshly laid egg adhering readily to
any substance it touches. In the northern and middle sections of the
United States two broods are reared, the first appearing in May, the
second and larger brood in midsummer or even August. The eggs deposited
by the last brood develop slowly in the cooler autumn weather, but
usually reach the pupal stage, in which they normally pass the winter.
Individual moths may, however, be seen about the apiary during June and
July, and even into the autumn, so that egg deposition is constantly
going on, and any combs removed from the hive and left unprotected by
bees, especially if in a warm apartment or a closed box, will soon be
in complete possession of the destructive larvæ, which wax fat and
soon reduce them to a mass of webs. The only remedies are to keep the
combs under the constant protection of the bees, or, if the colonies
are not populous enough to cover them fairly, the combs should be hung
so as to leave a space between them in a cupboard or large box which
can be closed tightly, so as to subject them for some time to the fumes
generated by throwing a handful or two of sulphur on live coals, or to
the odors of bisulphide of carbon in an open vial. Caution is needed in
the use of the latter, since it is highly inflammable.
Oriental races of bees are more energetic than others in clearing out
wax-moth larvæ, and Carniolans and Italians more so than the common
bees. But in colonies always supplied with good queens the wax-moth
larvæ make little headway, and it is therefore only the neglected
hives that are seriously troubled. Moth-trap attachments or moth-proof
hives are therefore of no use, unless, in the case of the former,
larvæ seeking a secure place in which to pupate may be caught; but
that implies frequent examination, and the same or less attention to
the colony itself will suffice to do away with almost any breeding of
moths. Hives proof against the entrance of wax-moth larvæ would, as
the statements here made regarding the breeding habits of the moth
indicate, exclude the bees also. From the foregoing it can be readily
seen that the attentive apiarist no longer regards the wax moth as a
serious pest.
BRAULA OR "BEE LOUSE."
A wingless dipteron, _Braula cæca_ Nitsch, known under the common name
of "bee louse," is a troublesome parasite on bees in Mediterranean
countries, the adults, which are very large in proportion to the host,
gathering on the thoraces of the workers, rarely of the drones, but
in great numbers on the queens. The writer has removed seventy-five
at one time from a queen, though ordinarily the numbers do not exceed
a dozen. When numerous they render the queen weak by the removal of
vital fluids. The insect has frequently been imported to this country
on queens with attendant bees, but thus far has probably gained no
foothold. Likely it will never do so in the North, but the case might
be different in any region resembling southern Europe in climate, and
it is by all means advisable to remove every one from any queen or
worker arriving here infested with them.
OTHER ENEMIES.
_Robber flies, dragon flies, etc._--Several species of _Asilus_ and
related predaceous Diptera do not live upon injurious insects alone,
but also capture and devour honey bees. They are more destructive in
the South than elsewhere. The same is true of the neuropterous insects
known as mosquito hawks, dragon flies, or devil's darning needles.
There seems to be no remedy for any of these except that of frightening
them away when noticed about the apiary. The "stinging bugs," belonging
in the hemipterous family Phymatidæ, often capture and destroy workers
as they visit the flowers. No remedy is practicable.
_Ants and wasps._--Some of the larger ants and social wasps are very
troublesome to the apiarist in tropical and even in subtropical
regions. They seize the workers and cut them in pieces with their
powerful jaws. Having once reduced the hive defenders, they even make
bold to enter and carry off the queen as well as help themselves to
honey. Trapping them with honey or with meat and killing them, as well
as destroying the nests when found, are the only remedies. The paper
nests are easily burned away, while an effectual remedy against ants is
to open the hill and pour in an ounce or two of bisulphide of carbon.
_Spiders._--Webs made about hive entrances often capture bees as well
as wax moths, and, notwithstanding this last-mentioned point in their
favor, they had better be removed.
_Toads and lizards._--These devour many bees, and whenever found near
the hives should be destroyed or removed to the vegetable garden.
_Birds._--Swallows and kingbirds have been accused of eating many bees.
It is probable that the destruction of injurious insects by them more
than makes amends for the bees taken. This was clearly proven in the
case of the kingbird, stomachs of which, examined at the United States
Department of Agriculture, showed only a very small percentage of honey
bees, and these mostly drones.
MAMMALS.
Mice gaining access to the hive during winter gnaw out among the combs
a nest cavity and eat honey, pollen, and bees. Low entrances, covered,
if found necessary, with a strip of tin, will prevent the mice from
gnawing larger holes, yet permit the bees to pass in and out. Skunks
sometimes disturb hive entrances and catch bees as they come out. This
is particularly vexatious in the winter, when colonies should be left
quiet. In mountain localities, bears, led by their fondness for honey,
still occasionally overturn beehives. The remedies for both of these
are, of course, shooting or trapping.
ROBBER BEES.
When forage is scarce in the field, bees belonging to different
colonies often wage fierce wars over the stores already in hives.
Thousands are killed and the victors relentlessly carry off as booty
every drop of honey from the vanquished hive, leaving its bees to
starve miserably. A great stir and loud buzzing in the hive of the
conquerors attests their rejoicing over the ill-gotten gains. Nor have
they any code of morals which inclines them to select as opponents
forces equal in strength to their own. With them "all's fair in war."
Their only object is plunder, and they therefore select the most
defenseless, a colony disorganized through loss of its queen being an
especial mark for a combined attack.
Extreme caution to prevent robbing is always advisable. A little
carelessness or neglect in the apiary early in the spring or toward
the latter part of the season may result in much loss. It is easier to
prevent robbing than to check it at once or without loss after it is
well under way. Leaving honey exposed about the apiary often induces
robbers to begin their work; hence extracting and similar work must
be done in bee-proof rooms whenever the bees are not gathering honey
freely. It may at such times be necessary to do all manipulating early
in the morning, before many of the bees have begun to fly, or later in
the day, after they have ceased, or even under a tent made of mosquito
netting and placed temporarily over the hive to be manipulated.
Queenless and weak colonies should be put in order if possible before
the honey flow ceases. In any event the entrances of such hives should
be contracted until but few or even no more than one bee can gain
access to the interior at one time. Professor Cheshire has devised an
excellent entrance block to prevent or check robbing. This is shown in
fig. 70, and is so simple that anyone can make it. When contracted and
placed at the hive entrance it will be seen that the robbers must make
their way through a narrow and bent passage, something they are loath
to attempt, especially if at the first onset they find the passage well
guarded.
[Illustration: Fig. 76.--Cheshire anti-robbing entrance: _st_,
stationary piece; _s_, slide; _p_, pin or stop. (Redrawn.)]
If robbing has begun it may sometimes be stopped by throwing coarse
grass or weeds over the entrance of the hive attacked, or by leaning
a pane of glass against its front, the entrance being, of course,
contracted as indicated above. These plans tend to confuse the robbers
for a time, and meanwhile the rightful occupants of the hive may be
able to organize for defense. If convenient the colony attacked may be
moved a distance of a half mile or more and placed as far as possible
from other apiaries until it can recuperate. Another plan in extreme
cases is to put the colony in a dark cellar for a few days, confining
the bees to the hive with wire cloth, so as to allow plenty of
ventilation, as described under the head of "Moving bees." When brought
out of the cellar it is well to place the colony on a new stand, apart
from the other bees, contract the entrance, and lean a board against
the front of the hive. It is also safest to bring it out late in the
day, even just at dusk, so the bees will begin flying from it gradually
and not attract the attention of robbers. It may be well, when removing
a colony from its stand to save it from robbers, to put in its place
a hive with combs containing a little honey and pollen. The robbers,
instead of scattering and entering adjacent hives, will continue to
visit the same stand, their numbers gradually diminishing as the honey
gives out and the pollen is sucked dry. If meanwhile the entrances of
adjoining hives have been contracted and these colonies are fairly
strong and in normal condition, individual robbers will be successively
repulsed as they appear. Quiet will thus be eventually restored.
LAYING WORKERS.
Although laying workers are not strictly enemies of their kind, their
work hastens the extinction of the colony to which they belong, in case
the latter has become queenless and is without the means of rearing
another queen. They cause the expenditure of the stores and strength
of the colonies in a vain though well-meant endeavor to perpetuate
their species; the eggs which laying workers deposit, and for whose
development through the larval stage much honey and pollen are
required, only resulting in the production of a lot of drones, for the
most part weak and dwarfed.
If not discovered until the hive is nearly depopulated, the remaining
old bees should be brushed off, and the combs, after the sealed drone
brood has been unmapped and jarred out, may be distributed among other
colonies. Should the affected colony still be worth saving, combs
containing emerging bees should be added and a queen introduced a few
days later, or a queen cell inserted, as soon as the added brood has
stocked the hive well with young bees.
=BOOKS AND JOURNALS RELATING TO APICULTURE.=
The following are among the leading books and journals relating to
apiculture:
BOOKS.
Langstroth on the Honey Bee. Revised edition, 1889. By Chas. Dadant
& Son.
Quinby's New Bee Keeping; or The Mysteries of Bee Keeping Explained.
1884. By L. C. Root.
The A B C of Bee Culture: A Cyclopædia of Everything Pertaining to the
Care of the Honey Bee. By A. I. Root.
Advanced Bee Culture: Its Methods and Management. 1891. By W. Z.
Hutchinson.
Bees and Bee Keeping, Scientific and Practical. By Frank R. Cheshire.
In two volumes: Vol. I (scientific), Vol. II (practical). Published
in London, England.
The Bee Keeper's Guide; or Manual of the Apiary. By A. J. Cook.
A Modern Bee Farm and its Economic Management. By S. Simmins. Published
in London, England.
The Blessed Bees. By John Allen.
Bee Keeping for Profit. By Dr. G. L. Tinker.
JOURNALS.
The American Bee Journal. Weekly. Chicago, Ill.
Gleanings in Bee Culture. Semimonthly. Medina, Ohio.
The Bee Keepers' Review. Monthly. Flint, Mich.
The American Bee Keeper. Monthly. Falconer, N. Y.
The Progressive Bee Keeper. Monthly. Higginsville, Mo.
The Southland Queen. Monthly. Beeville, Texas.
The Western Bee Keeper. Monthly. Denver, Colo.
* * * * *
Transcriber Note
Minor typos corrected. Illustrations repositioned where they split
paragraphs.