AU2002212005A1

AU2002212005A1 - Treatment with fluid dispenser for control of mites

Info

Publication number: AU2002212005A1
Application number: AU2002212005A
Authority: AU
Inventors: Vaclav Ruzicka
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-10-13
Filing date: 2001-10-12
Publication date: 2002-04-22
Also published as: AU2007254636A1; CA2323263A1; AR031267A1; WO2002030181A1; US20040229542A1; US6837770B2; EP1328150A1; AU2007254636B2; CA2323263C; NZ525785A

Description

TREATMENT WITH FLUID DISPENSER FOR CONTROL OF MITES

Field of the Invention

This invention relates to the field of methods for treating bees, for example controlling mites and in particular trachea and varroa mites.

Background of the Invention

It is well known to control trachea and varroa mites in a beehive by release of formic acid by evaporation at a controlled rate so as to achieve a concentration of acid fumes just below that of being harmful to the bees. In the prior art applicant is aware of German Patent No. 3427330 to Kramer. Kramer discloses a device for combating varroa mites in beehives where the device consists of soft fibre plates impregnated with formic acid and enclosed in a perforated plastic bag. In particular, the Kramer device consists of a 250-650 square centimeter soft fibre plate having 10 millimeters thickness which may be impregnated with 200-300 millilitres of concentrated formic acid. The soft fibre plate may be enclosed in a plastic film bag having 5-15 perforations on each side of the plate for a total exit area of 15-55 square centimeters.

Kramer teaches that, when placed horizontally in the hive over the brood area and above the brood chambers of the bee population, that the soft fibre plate formic acid dispenser controls varroa mites without harming the bees. The size of the fibre plate and extent of the perforation of the plastic bag result in controlled release of 85% formic acid concentration over a period of 7 days in August and 14 days in October.

There are many different ways of dispensing acid. They require multiple applications, or several adjustments to openings or cutting slots. They work on the principle of absorbency and evaporation by regulating the wrap openings. Generally, these dispensers are placed on the top of the cluster or on the bottom board. They may or may not work equally on colonies of different sizes. They also require additional space and equipment.

As reported in the American Bee Journal (March, 1996, at pages 190-192), the Kramer soft fibre plates are made of Pavatex (tm) and the plastic bags are of 0.15 millimeter thickness. For storage the plates are kept frozen and the plastic container kept air tight. Before application, the necessary evaporation holes are made in the plastic casing with around punching tool of 1.5 centimeters diameter. The number of holes varies according to the hive system and climate including the microclimate of the apiary. For a treatment, the plates are hung into the empty honey chamber by means of a honeycomb frame for seven days. For medium sized one story hives, Kramer teaches that a distance of 5 centimeters should be kept between the brood combs and the board.

The treatment efficiency of this method depends on the formic acid concentration in the hive air and on the duration of the treatment. It can be controlled on the basis of the amount of evaporated formic acid. Thus, the board has to be weighed before and after the treatment. If there is an evaporation of more than 7 grams of formic acid (85% concentration) per day, a treatment efficiency of more than 95% may be expected. If less than 7 grams evaporate, the treatment efficiency will be insufficient. To be reused, the Kramer plates must be reimpregnated with formic acid up to their gross weight of 250 grams of formic acid.

Summary of the Invention

The treatment fluid dispenser of the present invention includes a phenolic foam core snugly encased in a fluid impervious skin or sheath. The core is advantageously is a planar member, for example, a rectangular plate in shape. The fluid impervious skin or sheath is sealed about the phenolic foam core. The phenolic foam core has a great many capillary tubes longitudinally extending along the core. When it is desired to dispense formic acid or other treatment fluid from the phenolic foam core the fluid impervious skin and phenolic foam core is sliced transversely (i.e., across the capillary tubes), for example so as to separate the dispenser into two half sections or halves, alternatively referred to as half-pads. Each section or half is soaked in formic acid (advantageously 65% concentration) or other treatment fluid and hung vertically in a bee space so as to downwardly dispose an exposed surface of the phenolic foam core, to thereby evaporate acid at a uniform rate. The present invention works on the principles of the capillary tube and gravity. When soaked with, for example, acid, a 7-8 gram phenolic foam core will absorb approximately 230-240 grams of acid. Hung vertically, the capillaries will keep the liquid in the core without dripping after initial installation and gravity will pull down the fluid to replace evaporated fluid. Under contiOlled conditions of 24 degrees Celsius (74 degrees Fahrenheit) and 55% humidity, a half-pad will emit approximately six grams of acid a day.

Another key to the success of the present invention is its mounting location inside of the hive. The pads of the present invention may be 3/8 of an inch thick. Half-pads are placed in available bee space between the last comb and the side wall of the hive. In this location, in applicant's experience 95% of hives will leave the half-pads alone and maintain favourable temperature and humidity.

In summary, the treatment fluid dispenser for fluid treatment of bees according to the present invention includes a foam core having capillary cell structure and a fluid impervious skin mounted on and around the core. In one embodiment, the skin completely encloses the core awaiting sectioning. In such an embodiment the skin and the core are sectionable, for example by manual slicing by a knife, for exposing a cross-sectional surface of the core. This exposes ends of capillaries of the capillary cell structure to thereby provide a treatment fluid absorbing and evaporation surface. The core may then be used as a non-dripping fluid reservoir for the treatment fluid. The core may have a length greater than its width and may be generally plate- shaped or planar, parallelepiped or a rectangular parallelepiped. Each core has a thickness, a width and a length. The thickness is generally equal to a corresponding dimension of a bee-space in a hive. The length may be greater than twice the width so that, when bisected transversely of its longitudinal length by the cross-sectional surface bisecting transversely across the core so as to form two half sections, the half sections each are longer than they are wide, each half section having the cross-sectional surface at one end of its length.

The core is sized to store approximately 230-240 grams of formic acid or other treatment fluid, or approximately 15-120 grams in each half of the core once the core has been cut generally in half to form the evaporation surfaces on two of the cross-sectional surfaces thereby formed. In the case of formic acid, the evaporation surfaces on each half of the core are advantageously sized so as to release by evaporation approximately 6 grams of formic acid per day per half core when the half core has been soaked in formic acid and hung inverted in a bee space in a hive with the evaporation surface of the half core disposed downwardly of the body of the half core.

The method of the present invention includes the steps of:

(a) forming a sectioned core segment by sectioning the core so as to expose the cross- sectional surface of the core,

(b) soaking the sectioned core segment in formic acid or other treatment fluid so as to substantially fill the capillary cell structure, and

(c) hanging the core segment filled with the treatment fluid in a bee space between an outside comb and a side wall of the hive, so as to downwardly dispose the cross- sectional surface in the bee space. The sectioning of the core may be done by slicing by a knife perpendicularly across the core and the skin so as to bisect the core halfway along its length. The step of soaking the sectioned core segment may include soaking the sectioned core segment in 65% concentration formic acid.

Brief Description of the Drawings

Figure 1 is, in perspective view, the treatment fluid dispenser of the present invention.

Figure 2 is, in perspective view, a user holding a half-pad.

Figure 3 is, in perspective view, a comb having a treatment fluid dispenser mounted thereon being inserted into a bee space between an outside comb and a side wall in a hive.

Detailed Description of Embodiments of the Invention

A drawback of the prior art Kramer device is introduced by the reduced absorbency of the soft fibre Pavatex plates as compared to the phenolic foam core pad of the present invention. A further drawback is the use of a high (85%) acid concentration causes loss of queen bees. The reduced absorbency means that a Kramer device is more bulky, in that it requires 650cc (up to 1 lOOcc for a two story hive) of Pavatex material, which cannot conventionally be placed in any existing space in the hive, and additional box space is required. That is, 2 1/2 times as much material (five times as much material in the case of a two story hive) is required as compared to the formic acid dispenser pad of the present invention which is placed in existing bee space in any standard Langstroth hive. The present invention uses one half pad in one standard deep Langstroth box, and two half pads for a colony that is two boxes high. In the description as follows it is understood that the example given of formic acid is by way of illustration only and is not intended to be limiting, that is, the treatment fluid does not have to be formic acid. It may be other e.g. lactic, oxalic, citric acids or menthol liquid dissolved in water or alcohol or other treatment liquids may be used. It is possible to use other concentrations also, other than those specifically taught herein. Thus the present invention is intended for use with any fluid treatment that may be applied to a hive by metered evaporation of the fluid.

The treatment fluid dispenser of the present invention replaces the soft fiber plates taught in the prior art by Kramer with a phenolic foam core, for example of the type used to retain water in the base of floral presentations. One type of phenolic foam which has been successfully employed, is Standard Oasis (tm) Floral Foam, manufactured by Smither-Oasis, of Pickering, Ontario. It has been found that phenolic foam is highly absorbent of, and not affected by, formic acid. The phenolic foam cell structure provides a capillary action that results in a relatively constant evaporation rate given constant temperature and humidity, whereas the soft fibre Pavatex plates of the Kramer device are made of material such as employed in ceiling tiles or peg boards, that is, out of textile waste, and, it has been found, the absorbency is inconsistent.

As seen in Figure 1 and in cross-section in Figure 2, the formic acid dispenser pad

10 of the present invention in one embodiment is an approximately 225 cubic centimeters phenolic foam core 12 which, it has been found, will absorb approximately 230-240 grams of formic acid (65% concentration). A typical pad thickness is equivalent to a bee space, for example approximately 9.5 millimeters (3/8 of an inch). The phenolic foam acts as a formic acid reservoir holding the formic acid within the capillaries 12a of the foam. The foam is sufficiently rigid to allow a fluid impervious skin 14 to be snugly mounted on the foam, so as to enclose the foam. Skin 14 may be a plastic film or the like. Mounting of the skin on the foam core may be by shrink- wrapping, dipping, or by like means known in the art. Sealed pads are shipped for resale, empty for fill up by an applicator, franchise dealer or final user beekeeper himself, as formic acid is readily available commercially.

85% concentration acid may be thinned to 65% using water, either by weight or by volume, as it makes little difference.

In use, the fluid impervious skin of the pads, which may be formed as flat plates, are cut into half sections or half-pads 10a to allow soaking in acid and hanging to release the formic acid by evaporation. The cut half pad may be 4"x 5" in planform dimension. In use a half- pad is hung vertically for example by use of a nail or toothpick or staple to the comb, for example a typical comb measuring 10"x 18". The cut half-pad is mounted in the hive bee space so as to dispose the exposed cut surface 16 downwardly in a bee space between an outside comb and a side wall of the hive. A so-called outside comb is "outside" in the sense that, in the array of parallel closely adjacent combs in the hive, it is on the end of the array. In the present disclosure a bee space is defined as an empty space required and maintained by bees between two combs in a hive or between an outside comb and a hive side wall, in which the bees manoeuver and live.

In use, the formic acid dispenser of the present invention releases approximately 6 grams of 65% formic acid per day for approximately 24 days (for a brood cycle treatment). In a small hive, the rate of evaporation may be reduced by physically reducing the size of the evaporation surface. This may be done for example by masking the evaporation surface using tape. A single half pad 10a may be used for a single story hive. Both halves of a plate, that is two half-pads may be used for a two story hive. Each half pad 10a is hung with its exposed phenolic foam surface 16 disposed downwardly in bee space 18 between the outside comb 20 in the hive and the side wall 22 of the hive. The half pad may for example be secured by fastener 24 to the top bar of the frame of comb 20. As seen in Figure 3, comb 20 has been removed from the open hive 26 (once the adjacent comb has first been removed), a half pad fastened to the top of comb 20 so that the half pad hangs downwardly with exposed surface 16 downwardly disposed in bee space 18 once comb 20 has been re-inserted into the hive in direction A so as to be adjacent side wall 22. For installation, a user takes two combs out of the top box and lays them on the top of the combs remaining in the hive. The inside side wall of the hive body is cleaned. Half-pads, once cut and soaked in acid are mounted directly on the comb just taken out of the hive. The half-pad is stapled, nailed or pinned to the comb or frame top bar of the comb so that the exposed surface will be downward facing. The comb with the half- pad or half-pads attached to it are put back into the hive body with the half-pad or half-pads against the side wall. The other comb is put back into the hive. The half-pads are taken out after 24 days. If desired, the half-pads may be cleaned and then may be pinned to any sheltered wall to dry and then the evaporating surface re-cut to provide a re- finished surface for re-use. Half-pads may be stored in layers divided by wax paper.

Using a 65% concentration of acid reduces the initial impact of the acid fumes on the bees, making it more acceptable to the bees and queen losses rare. The concentration of acid fumes should be just below the level causing damage to adult bees. At this level, bees will increase ventilation, a roaring sound may be heard, and bees may climb out of the hive; however, applicant has observed they will settle down in 15-20 minutes. Small mortality or damage to new drones and freshly emerged bees are signs of this concentration level. These effects have been observed to be negligible during the spring treatment.

In cold climates, where four beehives may be grouped together to form a rectangle, the fluid dispensers of the present invention are advantageously mounted toward the center of the rectangle where the temperature typically is warmer than the outside temperature, especially if the hives have been insulated. For example, it has been found that the bees will keep the temperature in the applicator space or bee space between the outside comb and the side wall in an insulated hive between 22-26 degrees Celsius (70-80 degrees Fahrenheit) and humidity around 55% when the temperature outside can be as low as -5 degrees and as high as 28 degrees Celsius (20-83 degrees Fahrenheit), and the humidity from 20-90%. A typical pad thickness is equivalent to a bee space already existing in a hive, for example approximately 9.5 millimeters (3/8 of an inch). In the Kramer prior art evaporation method (holes on the side of the plate), typically 20 millimeter spacer bars are placed under horizontally placed plates. This extra space requirement has been addressed by requiring extra boxes to mount the Kramer plates in. For a large farm having thousands of hives, this equates to installing corresponding thousands of extra boxes. Further, the procedure recommended by Kramer of freezing the plates, which it has been found is done to allow for easier cutting of holes into plastic covering of the soft fibre plates, requires in that instance freezer space for, perhaps, thousands of plates.

Further, in the Kramer method a template is used to place perforations in the correct locations. Where there are hundreds or thousands of plates to be perforated, having to make between 7 and 15 perforations through a template for each plate makes for an excessive amount of work. In the fluid dispenser of the present invention, the phenolic foam allows for ease of cutting without having to be frozen, and the plate may be merely cut in half and hung as described above, without the requirement for templated perforations, although it has been found that quick and non- accurate pin-hole perforations made in the sealed end of a pad assists in quickly soaking up formic acid by a half-pad. In mass production, the sealed skin end may be pre-pin-hole perforated.

In terms of ease of shipping, an empty pad may be 4x10 inches in dimension (4x5 inches for a half pad), having a 3/8 inch thickness and weighing approximately 7-8 grams (each half pad then approximately 4 grams). The equivalent dispenser by Kramer weighs approximately 30-40 grams empty.

As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.

Claims

WHAT IS CLAIMED IS:

1. A treatment fluid dispenser for treatment of bees in a bee hive comprising:

a foam core having capillary cell structure,

a fluid impervious skin mounted on and around said core,

said skin and said core sectionable for exposing a cross-sectional surface of said core so as to expose ends of capillaries of said capillary cell structure, to thereby provide a fluid absorbing pad and evaporation surface, whereby said core may be used as a non-dripping fluid reservoir.

2. The dispenser of claim 1 wherein said core is generally plate-shaped and has a thickness, a width and a length, and wherein said thickness is generally equal to a bee-space in a hive.

3. The dispenser of claim 2 wherein said length is greater than said width and said core is generally a parallelepiped shape.

4. The dispenser of claim 3 wherein said length is greater than twice said width so that, when bisected transversely of its longitudinal length by said cross-sectional surface bisecting transversely across said core so as to form two half sections, said half sections each are longer than they are wide, each said half section having said cross-sectional surface at one end of its length.

5. The dispenser of claim 1 wherein said core is sized to store approximately 120 grams of formic acid in each half of said core once said core has been cut generally in half to form said evaporation surfaces on two of said cross-sectional surfaces thereby formed.

6. The dispenser of claim 5 wherein said evaporation surfaces on said each half of said core are sized so as to release by evaporation approximately 6 grams of formic acid per day per half of said core when said half of said core has been soaked in formic acid and hung inverted in a bee space in a hive with said evaporation surface of said half of said core disposed downwardly.

7. The dispenser of claim 1 wherein said core is a plate.

8. The dispenser of claim 1 wherein said core is planar.

9. The dispenser of claim 1 wherein said core is generally a rectangular parallelepiped.

10. The dispenser of claim 1 wherein said skin and said core are adapted to be manually sliced by a knife.

11. Using a fluid dispenser which includes a foam core having capillary cell structure, a fluid impervious skin mounted on and around the core, wherein the skin and the core are sectionable for exposing a cross-sectional surface of the core so as to expose ends of capillaries of the capillary cell structure, to thereby provide a fluid absorbing pad and evaporation surface, whereby the core may be used as a treatment fluid reservoir, a method of metered dispersing of treatment fluid in a bee hive comprising the steps of:

(a) forming a sectioned core segment by sectioning said core so as to expose said cross-sectional surface of said core,

(b) soaking said sectioned core segment in treatment fluid so as to substantially fill said capillary cell structure, (c) hanging said core segment filled with treatment fluid in a bee space between an outside comb and a side wall of said hive so as to downwardly dispose said cross- sectional surface in said bee space.

12. The method of claim 11 wherein said core is generally plate-shaped and has a thickness, a width and a length, the method further comprising the step of providing said thickness generally equal to a corresponding dimension of said bee-space.

13. The method of claim 12 further comprising providing said length greater than said width and providing said core as a generally parallelepiped shape.

14. The method of claim 13 further comprising providing said length greater than twice said width and said sectioning comprising bisecting said core and said skin transversely of their longitudinal length by forming said cross-sectional surface so as to bisect transversely across said core to form two half sections, whereby said half sections each are longer than they are wide, and each said half section has said cross-sectional surface at one end of its length.

15. The method of claim 11 wherein said treatment fluid is formic acid, and further comprising providing said core sized to store approximately 120 grams of formic acid in each half of said core once said core has been cut generally in half to form said evaporation surfaces on two of said cross-sectional surfaces thereby formed.

16. The method of claim 15 further comprising providing said evaporation surfaces on said each half of said core sized so as to release by evaporation approximately 6 grams of formic acid per day per half core after said half core has been soaked in formic acid and hung inverted in said bee space in said hive with said evaporation surface of said half core disposed downwardly.

17. The method of claim 11 wherein said sectioning of said core is slicing by a knife perpendicularly across said core and said skin so as to bisect said core halfway along its length.

18. The method of claim 11 wherein said treatment fluid is formic acid and wherein said step of soaking said sectioned core segment includes soaking said sectioned core segment in 65% concentration formic acid.