Mites are one of the greatest honey bee health threats. They affect honey production and the ability of bees to carry out pollination activities. Essential oils for honey bee mite control save beekeepers from the economic losses they stand to incur. Varroa mites, especially the Varroa destructor species, are responsible for the loss of honey bee colonies globally. They are believed to transmit bacterial and fungal parasites to honey bees. The total number of such colonies lost runs into the millions. A second type of mite affecting bees and honey bee colonies are tracheal mites. These too can be controlled through the use of essential oils for honey bee mite control.
While the destruction of Varroa mites is more widely covered in beekeeping, tracheal mites have received a lesser share of the spotlight. These honey bee mites affect the queen bee, worker bees and drones. They infect the tracheae of honey bees. They reproduce therein and draw nutrition from the bees’ haemolymph. Tracheae mites are well controlled by infusing essential oils for honey bee mite control into the bee feeder. A sugar or syrup mixture that contains a small amount of essential oils is fed to the bees when a colony is suspected or found out to be infested by tracheal mites.
About Essential Oils
Essential oils are produced by plants and stored within the plant for mostly defensive purposes. They offer protection against insects and sometimes animals by repelling them away or being injurious (poisonous) to the animals and insects when they ingest the plants. Extraction of essential oils is mainly by distillation and pressing. Some essential oils that may be used in honey bee mite control have the function of attracting potential pollinators.
Beehives that are infested with mites and left without treatment do not last more than 2 years. The use of essential oils in mite control also curbs spread of mites to other colonies in an apiary. Essential oils are an alternative to acaricides such as Apistan or Apivar. They are cheaper, environmentally friendly and pose fewer risks to the health of bees and honey consumers. Additionally, mites have not developed resistance to essential oils for honey bee mite control – unlike acaricides and other chemical treatments. Terpenes are the major component of essential oils.
Treating Varroa Mites with Essential Oils
The use of essential oils in controlling honey bee mite infestations is not natural to bees. The essential oils that you use must be acquired from a reliable source. This applies to other products you may add to essential oils. Additionally, the equipment you use to release essential oils in your beehives must also be got from trusted sources. The essential oils that you use should be food grade. The most common essential oils used in mite control are:
Lemongrass oil is very versatile oil with many uses for beekeepers. It has both anti-fungal and antiviral properties and often comes in a spray bottle. Lemongrass stimulates bees to eat food and is used to attract bees to hives. It also contains Citral and Geranic acid that are believed to kill honey bee mites. Lemongrass should be used sparingly in weak colonies since it may attract robber bees to your beehive.
This is an essential oil that comes from thyme plants. It is common in use against mites in beehives. Thyme oil is found in a number of commercial products for mite control. It acts by blocking mite’s pores. It also confuses mites and leads to their falling to the bottom of the hive. Used together with a screened bottom board, thyme oil will cause mites to fall to the ground and not be able to get back into your beehive. Thyme oil has anti-fungal properties too, and can prevent chalkbrood as well. The use of Thymol oil should be approached with caution. This is because Thymol oil is injurious to bees at high concentrations.
Eucalyptol, Menthol and Wintergreen Oil
These essential oils are useful as additions in treatments for Varroa and tracheal mites in beehives. They can be used in preparations to aid other more effective and directly acting essential oils for honey bee mite control. Wintergreen is very good for use with grease patties. When eaten by bees, it acts against tracheal mites with great effectiveness.
This essential oil is often used together with lemongrass to improve hive health. It works well against Varroa mites by blocking mite pores and disorienting them. A blend of lemon grass and spearmint has been found to help honey bees resistant to the pathogens that may be transmitted by mites. Unfortunately, this action by the two essential oils has not been exhaustively studied.
Peppermint in beehives is a strong masking scent. It does not mimic any honeybee pheromones.
Tea Tree Oil for Bees
Tea Tree oil is used in grease patties in controlling mites. It can be used in place of Wintergreen without any loss in effectiveness.
Pros and Cons of Using Essential Oils for Honey Bee Mite Control
- Essential oils for honey bee mite control offer beekeepers that are mindful about their footprint on the environment to practice beekeeping without resorting to chemicals.
- Essential oils when used in controlling honey bee mites reduce populations of honey bee mites or help the beekeeper completely rid their beehives of mites.
- There are various ways of applying essential oils into your beehive. Beekeepers have choice of the method they use. The chosen method should the one which is suitable and affordable to the beekeeper.
- Equipment used with essential oils in beehive mite infestation control is safe, easy to find in stores and can be purchased online. The equipment often has warranties as is common with most beekeeping supplies from reputable sellers and manufacturers.
- There are many different types of essential oils available for purchase. Beekeepers have enough in their hands when it comes to choices of essential oils for honey bee mite control. Small amounts of essential oils are required per application.
- Blends of two or more essential oils may give you better efficiency in controlling mites. They also help beekeepers achieve other desired behavioral effects in the beehive where they use them. Small amounts of essential oils are required per application.
- Beekeepers without adequate information may not easily arrive at the best essential oils for honey bee mite control to use. Different essential oils have varying effectiveness against mites of different types in honey bee colonies.
- Honey bees may be affected by essential oils for honey bee mite control. Each essential oil has varying effects based on its nature and concentration. Some oils when introduced into a beehive may alter bee behavior, place your colonies at different risks, or in worst case scenarios turn lethal to your bees.
- Essential oils for honey bee mite control works best with screened bottom boards. This may not be a preferred option for beekeepers who want their beehives to have solid bottom boards.
- The use of essential oils for honey bee mite control requires a period of time to lapse before beekeepers can safely harvest honey for human consumption.
- Essential oils are not cheap to purchase in the market. They are difficult to obtain form plants and thus dig deep into beekeepers’ pockets.
Factors Affecting the Effectiveness of Essential Oils
A number of factors affect the effectiveness of essential oils for honey bee mite control. They are mainly climatic factors generally around the relative humidity and ambient temperatures. These affect the evaporation rate of essential oils and consequently exposure of mites in the beehive. Adequate exposure is crucial for effectiveness of essential oils for honey bee mite control.
To go around the limitations of exposure to essential oils for honey bee mite control, a number of delivery systems are deployed. They allow for continuous release of the essential oils at a constant dose. These delivery systems for essential oils for honey bee mite control can operate for extended periods. Environmental conditions do not affect the performance of most commercial essential oils for honey bee mite control delivery systems. In addition to having a working essential oil for honey bee mite control and a consistent delivery system, it is important for beekeepers to apply treatments at appropriate times.
Essential Oil Therapy
Essential oil therapy to control mites in beehives and apiaries can work in two ways. First is direct contact with mites, and the second is through bees’ blood. Delivery of essential oils for honey bee mite control through bee blood requires the bees to feed on some of the essential oil. Mites sucking on the blood of such a bee show effects in a day or two.
Direct contact is more effective in killing off mites in a beehive. A bee that comes into contact with your essential oil preparation may transfer the oil to mites within the beehive. In most cases, a mite that comes into contact with the essential oil dies off in a few minutes. After direct contact with essential oils, mites find it difficult to climb onto the back of bees. Those that manage to reach the back of bees get poor attachment.
Bees that feed on an essential oil preparation may transfer the oil to fellow bees and larvae. The female Varroa mite that feeds on larvae or sucks blood of bees that has an effective essential oil dies soon after. Where mites do not die after indirect contact with essential oils, their reproduction is affected. This may lead to more time being taken to control an infestation, but it is nevertheless effective. Feeding on essential oils for honey bee mite control is very effective against tracheal mites. Contact between the mite and the oil affect the mites and they die off.
Tracheal mites are generally impacted by essential oils for honey bee mite control. Their breeding suffers when they are exposed to grease patties. The use of essential oils for honey bee tracheal mite control is mainly done when there is no honey collection for human consumption scheduled to take place.
Beekeepers have a number of dispersal methods to choose from when using essential oils for honey bee mite control. The varying methods have different levels of efficiency and effectiveness. They utilize different technologies. Some are easy to apply, while others have a high level of complexity.
1. Grease Patties
Grease patties are the easiest way to apply essential oils for honey bee mite control. They are placed between beehive frames on the top sides. Bees coming into close proximity with the grease patties lead to mites that are on bees getting into contact with the grease patty. The initial use of grease patties over time has been to control tracheal mites. In recent years, following an upsurge in the number of beekeepers seeking natural and organic beekeeping, grease patches have found use as a Varroa mite control method too. Grease patties should not be used when honey harvesting is due. They may also lead to infestation of your beehive by small hive beetles.
A simple grease patty recipe is made by mixing one pound of solid vegetable shortening and three pounds of sugar. A small amount of essential oils is then added to add odor that attracts bees to the preparation. A suitable container should be used to hold the patty in your beehive. You may also use an absorbent material that acts as a wick to gradually release the grease patty to bees as they come into contact with it within the hive.
2. Oil Traps
Beekeepers using essential oils for honey bee mite control may use a base with an oil trap. The oil trap is accessed from behind the base and does not disturb your hive. You may winter your hive with the oil trap. The traps in the market fit different sizes of hives including 7-frame and 10-frame beehives. Commercially produced oil traps for use with essential oils for honey bee mite control release a constant amount of the essential oils into the beehive. They are however dependent on bees coming into contact with the oil trap. Using an oil trap removes the possibility of using a screened bottom board, or renders it useless in mite control if it is already present in your beehive.
Evaporators/vaporizers of varying sizes are also used to disperse essential oils for honey bee mite control. Notable evaporators are electric and smoke cannons. Electric vaporizers that are suitable for both beginner and professional beekeepers use DC (direct current). Those running on AC (Alternating Current) are trouble for beekeepers during winter, and who may not easily get mains electricity to their apiary’s outdoor location. They are operated using varying energy sources. The best electric vaporizers work with a variety of batteries and use up little energy to effectively vaporize essential oils for honey bee mite control. Most vaporizers give beekeepers a good period of operation between battery swaps. They give excellent distribution of essential oils.
The smoke cannon is a contraption that employs the same ideas as a beehive smoker. It blows smoke from the leaves or crystals of the plant bearing the essential oil of your choice. This smoke when blown into a hive bears helps you with mite control. Smoking bees may stress them out. This makes the smoke cannon unsuitable as a delivery method for essential oils for honey bee mite control. The amount of essential oils carried into the hive through smoke is also often in question. Heavy duty modern essential oil smoke cannons use water, ethyl, 96% alcohol or purified kerosene as solvents.
Popular electric evaporators for essential oils for honey bee mite control are easy to use and heat up fast. They are portable and compact. Manufacturers of electric evaporators may supply them with spoons or scoops to measure and add essential oils. The temperature of the heating part may reach 2500C. The vaporizer itself is long, with a heating part on one end of a rod. It has a handle and a power cord may dangle from the handle or on the heating part of vaporizers. The handles of vaporizers are made of wood. The use of wood insulation allows safe handling of the vaporizer by beekeepers. Electric vaporizers running on DC are supplied using safety battery clips. Each battery clip should be attached to the correct battery terminal during use.
A Final Word
It must be noted that not all essential oils are effective in mite control in beehives. A blend that includes Thymol in the essential oil has been found to be most effective in honey bee mite control. Essential oils for honey bee mite control have a mite mortality rate above 90%, and closer to 100%. The residues of essential oils in honey are low even when they are used on a long-term basis. A single treatment with essential oils is often not adequate to lower mite populations to levels where they do not cause economic injury. Essential oils can be easily applied alongside other treatments and methods in an integrated management strategy for Varroa mite control by beekeepers.
Have you used the essential oils for Varroa mite control in your beehives? Leave a comment below and let us know what you think of it.