CHAPTER XIV Edit
DISEASES AND ENEMIES OF BEES Edit
BEES, like all other stock, may be subject to disease, and other enemies that will ravage them if the conditions are favorable, but as a matter of fact the danger is very remote if the bees are given the proper care they demand. In my many years of experience, I have never had a case of disease among my bees, and the predations of natural enemies such as birds, skunks, snakes, and mice have been of such rare occurrence as to be infinitesimal factors in all the years that have passed. It is well, however, to describe some of the diseases to which bees are prone, and to point out preventive and curative measures for any possible condition that may arise. Foul Brood is the most dreaded of diseases. It is of two varieties, the American and the European, and, unless speedily cured, will in a short time ravish and destroy an entire apiary.
It is primarily a bacterial disease of the larva, and when once a spore of the disease takes possession of a larva, it spreads with wonderful rapidity. It is usually transmitted to a healthy colony in one of two ways : either by the introduction of a new queen that may have come from some section of the country where the disease is prevalent, or by the bees of a healthy colony robbing honey from an infected hive, and the spores carried in the honey that was robbed. This danger has led a great many beekeepers to kill all of the attendant bees that accompany the queen in her journey through the mails, and reserve only the queen for introduction; and this is a most excellent precautionary measure to adopt.
Beginners are very liable to confuse chilled dead brood, or pickled brood, with foul brood, and become needlessly alarmed; but when once the real thing has taken possession of a colony, the condition of the brood, and the terrible stench, will enable him to detect its presence at once. The American foul brood is easily distinguished from the European foul or black brood by its sticky or ropy nature, as a very easy test will prove. One of its first symptoms is that some of the brood will fail to hatch, and the cappings of the cells will assume a sunken appearance, and if a match or wooden toothpick is inserted into the cell and gently pulled out, a foul-smelling mucilaginous substance will adhere to it. The larva soon loses its shape, and becomes a sticky mass, smelling very much like ordinary glue. The offensive odor is not very pronounced in its early stages, but as the disease advances, it becomes more and more noticeable.
The larvse that are attacked are usually sealed over by the bees, but this is not always the case, as it frequently happens that the unsealed brood is destroyed, especially if the infection is well under way, and the bacteria fully at work. The color of the sticky mass is like strong coffee with milk added, but since these conditions prevail to a certain extent in the cases of chilled and pickled brood, we cannot be sure it is the real foul brood unless we test it with a toothpick or match as outlined above; if it adheres to the match, and can be drawn out to a distance of onehalf or one inch, we can then be reasonably certain that we have a case of real foul brood on hand. The progress of this disease is very rapid, as all the combs of the hive are more or less certain to be infected, the honey included, and when the queen lays new eggs the honey that is fed to the larvae will contain a lot of spores, and the new larvae will in turn become diseased.
After a time the bacteria are so prevalent in the hive that no brood can be reared, and as the old bees die off the colony becomes so weak that it becomes an easy prey to robber bees, who will in turn carry its infected honey to healthy colonies, and in this way the disease will spread with alarming rapidity. Sometimes a beginner will imagine he has a case of foul brood because the bees in warm weather will sometimes leave the cappings of brood they are sealing in an unfinished shape, so that there will be a small pinhole opening in the centre of the cell, but if the larvse are nice and white, there is no occasion for alarm. In the case of foul brood the perforation will not be regular and rounded, but will have ragged edges, and this is due to the fact that the bees seem to have an instinct that something is wrong with the brood, since it fails to hatch, and they tear away a part of the cappings to determine what is the matter. The best preventive measure is to take such good care of every colony that it is always strong, for bees are like human beings, the stronger are better able to resist disease in every form; and as a rule a strong colony is seldom affected unless the spores are directly introduced by the bees from some already infected source.
After the treatment of a diseased colony, it is absolutely essential that all tools and implements that have been used shall be kept from the other bees till they have been thoroughly boiled and sterilized, if they are to be used again on a healthy colony. Even the clothing that was worn while treating a dis* eased colony is a perfect means of transmission, and there have been cases where careless inspectors of foul brood have gone from a diseased apiary to a healthy one without change or fumigation of their wearing apparel, and rendered the infection of the healthy apiary almost a foregone conclusion. The entrance to the hive of a diseased colony should 4 be made smaller to prevent the possibility of robbing, and all manipulation should be done late in the day after the bees have ceased to fly, or serious consequences will follow. A great many curative methods have been tried in the past, using salicylic acid, phenol, carbolic acid, and formaldehyde, but the results were in no sense satisfactory.
William McEvoy of Woodburn, Ontario, Canada, claims to have had great success in the treatment of thousands of colonies, and he puts them back into the hives out of which they came; but there have been a large number of cases where the disease has appeared again in the hives whose bodies and fixtures were not disinfected. His plan is to take the infected colony in the height of the honey season, and in the evening shake the bees from their infected combs into their old hive, giving them frames with foundation starters, and let them work on them for four days. The bees will in that time have worked out some comb, and have stored in it all the diseased honey they carried in their sacs from the diseased combs, and then in the evening of the fourth day, he takes the new combs out and shakes the bees on new frames of foundation; and he claims that the cure will be complete as all the infected combs with their honey will be removed from the hive. He does not advocate the disinfection of the old hive, but a little extra work in this respect will save worry and possible return of the disease, and for one's peace of mind it will be well to pour a strong solution of boiling water and carbolic acid over the hive body, lid, and bottom, letting it soak in all sides and run into every crevice.
A good plan for disinfection of the hive body is to pour some gasolene all over it and touch a match to it and let it burn off, and if too much is not used, and the blaze carefully watched, no harm will result to the hive. The old combs should be burned over a good fire and the ashes buried, this work being done at night; but if the combs are filled with honey, the honey can be extracted and boiled, and used for feed, but there is always the possibility of infected honey, with its fearful consequences, remaining in the extractor. European foul or black brood differs in many ways from the American foul brood, and first made its appearance in this country in New York state. Many an apiary was devastated by it, and it has been only in recent years that we seem to have found a cure. While this form of foul brood in some respects is similar to the American kind, yet there are several respects in which it very materially differs. In the first place, it is very rarely ropy in its consistency, and the dead larva seldom loses its shape and becomes a sticky mass, but on the contrary, it assumes a watery consistency, and confines itself to the grub itself, which in time turns a dark brown. I have seen it a coffee black in some hives that were infected. Only in its latter stages does it become offensive like American foul brood, but even then it is hardly as foulsmelling. Mr. E. F. Phillips, Ph.D., in charge of the Department of Apiculture at Washington, D.C., is one of the leading experts on bee diseases and will gladly render a report on any specimen that may be sent to him in a tightly sealed tin box; so that any beekeeper may determine beyond the shadow of a doubt just what disease he has to contend with. The usual treatment for black brood up to a short time ago was identically the same as that used for American foul brood, but during recent years the late Mr. Alexander, of Delanson, New York, experimented for a considerable period and finally discovered a treatment that seems to be effective in every case. His plan was to remove from every diseased colony its queen, and by cutting out all queen cells already started, leave the colony in a hopelessly queenless condition for at least three weeks, during which period no new brood developed. During this time all of the healthy brood in the hive will hatch, and the colony, in anticipation of a new queen, will, as all queenless colonies do, clean out and polish every cell for the new eggs; this cleaning and polishing process seems to eradicate the disease completely. Some beekeepers were not very successful in following this method, but in the hands of Mr. Alexander it was a pronounced success, and a personal examination of some colonies that were treated the season before failed to reveal to me any indication of the presence of foul brood in any form. It might be said that during a good honey flow a strong colony runs little chance of becoming diseased. Do all the work with a diseased colony in the evening, and prevent even a single bee from another colony getting access to any of the diseased honey or implements, for one bee carrying even the minutest drop of infected honey to a healthy hive can spread the germs as effectively as a thousand. Bee Paralysis is another disease that is sometimes found in warm climates, but is rarely known in the North, and, as a whole colony is seldom affected by it, it is not a cause for alarm.
An occasional bee with its abdomen greatly distended will be found crawling along the alighting-board evidently in an effort to get away from the hive to die; and this is about the extent of its ravages in the North; though the ravages of the disease in warm climates have been known to clean out an entire apiary, and is as dreaded as foul brood. Sometimes the removal and killing of the queen will work a cure, and would seem to indicate that the disease was inherited from the queen, but some experiments have proved that dequeening fails to accomplish the desired result. Perhaps the best way to cure it is to remove from the diseased hive all of its frames of brood and give them without their bees to a strong colony for a day or more, and giving a liberal sprinkling of powdered sulphur to the bees remaining in the affected colony; thus a cure is generally accomplished. Spring dwindling of a colony is not a disease, but rather a condition, and is usually the result of a cold spell following the removal of bees from their winter cellars. Uniting such colonies has not proved the best plan, and a much better one is to place a queen-excluding zinc on top of a strong colony and on it set the dwindled one, queen, bees, combs, and all, and when it has built up to fair strength, put it back on its stand. There are a number of enemies that prey upon the bees, and as some of them are hard to reach, and as the results of their predations are minor, it is one of the phases of bee-keeping where the beekeeper has to take a chance, as it were. There are certain insectivorous birds that catch and eat bees while in flight, and many a good virgin queen in her matrimonial flight has been gobbled up, but this is a chance we have to take, and I know no means of stopping it. In warm climates the dragon flies kill a large number of virgin queens when in flight, and in certain sections they are so numerous that commercial queen-rearing is well nigh an impossibility.
Frogs will often in the cool of the evening place themselves at the entrance of a hive of bees, and many a luckless bee has been ensnared in their long tongues to make a tasty morsel for them. Field mice and small snakes will often invade a hive, and if the colony is weak will work havoc with the combs, but, with the exception of mice, the setting of the hive upon a stand a foot or so above the ground will prevent their ravages. An apiary is very likely to be the lurkingplace of skunks, who seem to have a fondness for bees, and the little rascals will, in the shadow of night, scratch on the alightingboard of a hive to lure the sentinels out for investigation, only to be gobbled up by their odoriferous enemies. A few traps baited with the proper bait will soon rid the yard of these pests; but care should be used in their handling if they are still alive when trapped. In some sections of the country, the fondness of bears for honey has led them to topple over the hives and work much damage, but a little watchfulness on the part of the beekeeper, with the aid of a good rifle, will result in breaking it up.
Sometimes a mouse or small snake will invade a strong colony and be stung to death, and when the bees find that they are unable to remove the carcass, they will proceed to propolize or mummify it and glue it securely to the bottom board of the hive. In lifting hives, with their bottom boards, I have frequently found a live snake, or nest of mice, enticed there no doubt by the warmth of the hive and the possibilities of a rich repast; but as these are things of but rare occurrence, no serious harm is likely to occur.