GB2339694A

GB2339694A - Pesticide composition for woodlice

Info

Publication number: GB2339694A
Application number: GB9917278A
Authority: GB
Inventors: Colin Leslie Young
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-07-23
Filing date: 1999-07-22
Publication date: 2000-02-09
Anticipated expiration: 2019-07-22
Also published as: GB9917278D0; AUPP481098A0; GB2339694B

Description

2339694 Pesticide The present invention relates to a pesticide composition

for woodlice, including sowbugs and pillbugs. More particularly, the invention provides a pesticide composition for woodlice, more commonly known as slaters, which is non-phytotoxic and harmless to nontarget animals and human beings.

The common slaers, Oniscus asellus, Porcellio scaber (the common woodlouse) and Armadillidium vulgare (the pill woodlouse) are common garden pests which can cause significant problems in the home garden throughout the world. These woodlice are found in most parts of the earth from the northern tundra to the equator, from coastal areas to high in the mountains. They seek out damp, protected places during the day but leave these during the moist night when they become active. Although they eat dead plant material, they also attack young plant roots and can cause significant problems, particularly in container-grown plants. In sandy soil, they often bury themselves in the soil and are potentially significant pests in such areas. In Australia, for example, in the Perth region of Western Australia, they are considered a pest in suburban gardens.

Woodlice belong to the phylum Arthropoda, class Crustacea, order Isopods, suborder Oniscidea. These pests are members of the Crustacean family and are not insects. Nearly all arthropods that live in the sea are crustaceans but woodlice, and a few amphipods, are the only crustaceans to live on land with any success. It is clear from the fact that death to woodlice may be caused by water overload, that these animals have forfeited their aquatic potential to some extent.

2 Woodlice cannot survive for more than a day or two away from moist areas; however, they thrive in bark or mossbased potting mixes and in mulches. Since there is an increased use of mulches in the home garden, it is to be expected that the problem of unwanted woodlice will correspondingly increase. Woodlice will also at times invade damp basement areas as well as the first floors of houses. When this occurs, they are almost always present in considerable numbers in the soil and under plants immediately outside the house.

Sowbugs, one class of woodlice, such as Porcellio scaber (the common woodlouse) and Oniscus asellus are not able to roll up into a ball, but the pillbugs, another class is of woodlice, such as Armadillidium vulgare can roll up into a ball when disturbed or under water stress. Both pillbugs and sowbugs have six pairs of legs initially increasing to seven pairs after the first or subsequent molts (Heeley, W., (1941) "Observations on the life histories of some terrestrial isopods," Rroc. Zool. Soc., London, B, 3, pp79-149). The biologies of pillbugs and sowbugs are similar (Sutton, S.L. , "Woodlice", Ginn and Co. London (1972), republished by Pergamon Press, Oxford (1980)). The eggs hatch in a brood pouch (marsupium), the average number in a brood being of the order of between twenty and thirty. It appears that two broods per year is the most common although Heeley (1941), questioned the generality of this, pointing out that the number of broods was probably influenced by climatic conditions. Both sowbugs and pillbugs have a lifespan of about two years.

Where woodlice have become a problem, they have until now been controlled by pesticides such as methiocarb, bendiocarb or diazinon. Diazinon is a contact-action pesticide which is also phytotoxic causing damage to a number of plants. Methiocarb and bendiocarb are anticholinesterase agents. These substances inhibit the action of cholinesterases and thereby destroy or interfere with the conduction of nerve impulses.

Woodlice have many natural predators. Common shrews are known to consume vast numbers of woodlice. Other animals known to eat them include toads, frogs, lizards, birds, spiders and hedgehogs. The possibility of secondary poisoning (i.e. poisoning of animals which have eaten woodlice killed by a pesticide) is of some concern, in particular, in the case of methiocarb. The pesticides currently used to control woodlice are therefore toxic to a wide range of animals including humans. These chemicals also pose a considerable threat to non-target plants. There is therefore a need for a less toxic and more specific pesticide.

The common woodlouse species, Porcellio scaber, is widespread in Australia and is a common component of garden fauna and was thus chosen as a test organism as it is ubiquitous in its distribution.

Accordingly, it is an object of the present invention to provide a pesticidal composition for woodlice and preferably, one which is non-phytotoxic and will not be the cause of secondary or accidental poisoning of other non-target animals, such as pets and human beings. Such a pesticide would offer considerable environmental advantages.

The toxicity of iron chelates to non-target animals has previously been investigated in relation to a study on snails (Young, C.L., Australian Patent Application No. 689399) and selected metal complexones were found to be considerably less toxic than methiocarb, which is presently the usually preferred pesticide of choice commonly used for woodlice, in spite of its possible 4 side-effects. Indeed, these metal complexones are used in medicinal applications to relieve anaemia.

The effectiveness of such complexones is not very temperature- or humidity-dependent, being comparable to methiocarb in this respect. Therefore, their use in damp situations, which woodlice invariably inhabit, would not be expected to present a problem. Further, these metal complexones are neither insecticides nor acaracides and pesticides for the control of woodlice based on themwill not kill earthworms, the mainly beneficial carabid beetles, ladybird larvae or honey bees.

The term "metal complexone" is used herein in its broadest sense and refers to a chelate of a metal with at least one ligand of the complexone type. Preferably, these are chelates which have at least one imidodiacetic acid, [-N(CH2Co2H)21 group or two aminoacetic acid, [-NHCH2Co2H] groups, where one or both of the methylene hydrogen/s may be replaced by other substituents. These compounds form stable complexes with almost all cations. The chemistry of those substances, including the equilibrium constants for the formation of the metal chelates, have been very extensively studied (Anderegg, in "Comprehensive Coordination Chemistry," (1987), Vol 2, Chapter 20.3).

According to one embodiment of the present invention, there is provided a pesticide composition for woodlice, including an effective amount of a metal complexone and a suitable carrier therefor.

Preferably, the metal of the metal complexone is selected from aluminium or iron. Most preferably, the metal is iron(III).

Preferably, the complexone of the metal complexone is selected from ethylenediaminetetraacetic acid (EDTA) or ethylenediaminedisuccinic acid (EDDS). Most preferably, the metal complexone is ferric EDTA or the hydroxy-metal complexone derivative of FeEDTA, (Fe(III)(OH)EDTA]2-.

Typically, the pesticide composition includes a metal complexone in an amount of at least 4.5% by weight of the total composition of the pesticide. More preferably, the metal complexone comprises about 4.5% to about 12% by weight of the composition, when the metal complexone is jFe (III) (OH)EDTA]2-. Most preferably, [ Fe (I I I) (OH) EDTA] 2- comprises about 6% by weight of the composition.

In a preferred form of the invention, the carrier for the metal complexone usually includes a cereal, wheat flour, corn flour, bran, arrowroot or rice flour; carrot, beer, rice hulls, comminuted cuttle fish, starch or gelatin, or mixtures thereof, so that the woodlouse is attracted to the pesticide composition in the form of a bait. Non- nutrient carriers of interest include nonnutrient polymeric materials, pumice, carbon and materials useful as carriers for pesticides. The pesticide composition may also contain other additives known in the art as phagostimulants, for example, sucrose or mollasses; lubricants such as paraffin wax, white oil or casein; and flavourings such as BITREXO (a registered trade mark) which imparts a bitter taste and renders the bait less attractive to non-target animals and human beings. In order to inhibit deterioration of the bait, preservatives such as sodium benzoate, vitamin E, alpha-tocopherol, 4nitrophenol, ascorbic acid, methyl paraben, propyl paraben or sodium bisulfite may also be included.

Preferably further, a water-proofing agent is included to prolong the life of the bait. Such a water-proofing agent preferably comprises a fatty acid alcohol in an amount in the range between about 1% and 5% by weight of the total composition. More preferably, the fatty acid alcohol is selected from the group of C16_C18 fatty acid alcohols. Most preferably, the C16-C1, fatty acid alcohol comprises about 2% by weight of the total composition. Most preferably, the C,,-C,8 fatty acid alcohol is HYDRENOL MY, which is a mixture of hexadecanol, heptadecanol and octadecanol. (HYDRENOL MY is a registered trade mark of Henkel Australia Pty. Ltd.). In another pre, ferred form of the invention, the waterproofing agent is guar gum in combination with lotus bean gum to provide a harder, more water-resistant pellet for use in particularly wet conditions.

is The pesticide composition is advantageously presented in a solid bait form such as tablets, powders, granules or pellets or in a form which could assist with applying the pesticide composition as a coating. Those skilled in the art will appreciate that it is preferable to prepare the products which are the subject of the invention in a form that is easy for consumers to use. Pellets, for example, can be easily scattered from a box across the area to be protected, whilst a coating formulation could assist in the application of the product to the bottom of pot plant or flower box containers.

Typically, to increase the density of the pesticide composition before pelletising to reduce the airborne content and hence wastage of the composition, a filler is added to the carrier. Preferably, the filler is selected from calcium or potassium carbonate, but is not limited to these. Typically, the composition contains about 1% but not exceeding 5% of a metal carbonate as a filler. When the metal carbonate is calcium carbonate, the preferred concentration is in the range between 7 about 2% and 3% by weight of the total composition. When the metal carbonate is potassium carbonate, the preferred concentration is in the range between about 4% and 5% by weight of the total composition. Such a formulation with added carbonate as filler provides a non-acidic pH and this serves to aid in the palatability characteristics of the bait, thereby increasing its efficacy.

In a preferred form of the invention, the pesticide composition fu_ther comprises an effective amount of a surfactant to compensate for any loss of efficacy of any iron (III) which may become bound up by phytates present in the flour. Preferably, the surfactant is sodium dodecyl sulphate, but is not limited to this. More preferably, the sodium dodecyl sulphate is present in an amount between about 0.2% and 0.3% by weight of the total composition.

According to yet another aspect of the invention, the metal complexone comprises a metal complexone in combination with at least one other pesticide. Typically, the other pesticide is selected from methiocarb, bendiocarb or diazinon.

A further aspect of the invention is the use of a metal complexone as a pesticide for woodlice, wherein the pesticide is applied to the area infested by the woodlice in an appropriate manner. Preferably, the mode of application is either in the form of scattering the pesticide composition in the form of bait pellets over the area to be protected or by applying a coating formulation including the pesticide composition to the area inhabited by woodlice.

Where the pesticide composition is in the form of bait pellets, according to another aspect of the invention, the method of preparation of the pellets includes the steps of:

(i) blending the metal complexone and the carrier together to form a blended composition; (ii) heating the blended composition for a time between about 1 to 5 minutes in the presence of steam at an ambient temperature in the range between 800C and 100C; (iii) maintaining the composition at the ambient temperature between about 10 and 30 seconds; and (iv) forming the blended composition into one or more pellets.

Preferably, step (ii) is carried out at about 900C for about 2 minutes, whereafter step (iii) is carried out for about 15 seconds. Preferably, the blended composition is formed into pellets under pressure.

According to another form of the invention, the pesticide composition is included in a coating formulation for application to items which are eaten by woodlice or act as a shelter for them, such as the underside of pots and containers. The coating is consumed by the woodlice and acts as a stomach poison. In this form of the invention, the carrier for the metal complexone in the pesticide composition includes an edible binder to provide a formulation having a gluelike consistency. Preferably, the binder is selected from a polyvinyl acetate-based binder, gum arabic or gum acacia. More preferably, the binder is a polyvinyl acetate-based binder. Most preferably, the polyvinyl acetate-based binder is TERRA CONTROLO. (TERRA CONTROLOis a registered trade mark of Henkel Australia Pty Ltd).

9 A further aspect of the invention relates to the use of the coating formulation as applied to the underside of pots and containers.

A still further aspect of the invention is the use of a metal complexone as a pesticide for woodlice in a pesticide composition, especially a pesticide composition or coating formulation according to the invention.

A yet still further apsect of the invention is method of pesticidal treatment to combat woodlouse infestation of an area which method comprises applying to at least part of said area a pesticide composition or a coating formulation according to the invention.

Where the terms "comprise", "comprises", "comprised" or IT comprising" are used in this specification, they are to be interpreted as specifying the presence of the stated features, integers, steps or components referred to, but not to preclude the presence or addition of one or more feature, integer, step, component or group thereof.

Examples

The invention will now be described, further explained and illustrated with reference to the following nonlimiting Examples.

Study of the toxicity of various metal salts and chelates as well as several commercially available formulations A number of different metal chelates were investigated during this study.

The experimental set up consisted of containers of 1 - 10 litre capacity with approximately 150 ml of coarse moist pine bark potting mix. Each container had a number of small 0.5 mm holes in the lid to allow for air circulation. The containers were placed on a verandah so that rain could not enter the containers, but they were subject to natural light. Four pellets of each treatment were added to each container along with one woodlouse. After five days, the woodlice were examined to determine whether they were alive or dead. Great 10 care was sometimes required to establish whether the woodlice were,in fact, dead. As stated above, the common woodlouse often "plays" dead on being disturbed, whereas the pill woodlouse is able to roll up into a ball.

The various formulations used are provided below and the death rates for the various formulations are given in Tables 1 and 2.

Formulations used in this study Code Formulation Bay BAYSOL' 2. 0% methiocarb in a grain-based bait 25 Multil MULTIGUARD" containing 9% oxo-dimer of ferric EDTA in bran/flour bait Multi2 4.5% oxo-dimer of ferric EDTA + synergist in 30 bran/flour bait (soft pellet) Multi3 6% oxo-dimer of ferric EDTA in bran/flour bait (very hard pellet) E 1 7.1% ferric orthophosphate in flour bait E2 10.3% ferrous sulphate in flour bait F1 4.2% ferric EDTA + 3.4% calcium sulphate in flour bait F2 4.2% ferric EDTA + 7.4% calcium sulphate in flour bait CH1 5.0% Hydroxyethylenediaminetriacetic acid ferric salt (DISSOLVINEO H-Fe-13) in flour bait CH2 9.6%.'Ethylenediaminebis[(2 hydroxyphenyl)acetic acid] ferric sodium salt (DISSOLVINEO Q-Fe-6) in flour bait CH3 5.2% Diethylenetriaminopentaacetic acid ferric sodium salt (DISSOLVINEO D-Fe-11) in flour bait ESC Escargo! containing 1% ferric phosphate in an inert bait Org 0.28% Fe as iron(III)-3-hydroxy-2-methyl-4 pyrone complex in flour bait PSO 1.0% ferric EDTA + 0.27% sodium dodecyl sulphate in flour bait PhylO 4.86% ferric EDTA + 3.16% sodium phytate in flour bait A16 0.67% ALKANATE CS' in flour bait Zn 8.9% zinc EDTA in flour bait Cu 8.6% copper EDTA in flour bait Alac 10.3% aluminium trisacetylacetonate in flour bait Met 6.0% metaldehyde in grain bait (LIMAXII) Ben 0.5% bendiocarb in talc BAYSOLO, MULTIGUARD", DISSOLVINEO, ESCARGO! 0, ALKANATE cso and LIMAX are registered trade marks of Bayer, Multicrop (Aust.), Akzo-Nobel, Garden Alive!, ICI and RhonePoulenc, respectively.

Example 1 Ten containers.'for each different formulation trialed were set up containing one woodlouse each. A blank pellet containing no metal complexone was used as a control. The species of woodlouse was Porcellio scaber.

After five days, the number of dead woodlice in each group of containers was determined. The results are shown in Table 1.

Table 1 Number of woodlice dead after-5 days in the various treatments Porce22io scaber Treatment #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 Total Control 0/1 0/1 0/1 0/1 Oil 0/1 0/1 0/1 0/1 0/1 0/10 Bay 1/1 1/1 1/1 Oil 1/1 0/1 1/1 1/1 1/1 1/1 8110 Multil 1/1 1/1 1/1 1/1 111 1/1 1/1 1/1 1/1 1/1 10/10 MuI62 1/1 111 1/1 0/1 1/1 1/1 1/1 1/1 0/1 1/1 8/10 Multi3 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 10/10 El 0/1 Oil 1/1 0/1 0/1 0/1 0/1 0/1 0/1 1/1 2/10 E2 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/10 F1 0/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 1/1 9/10 F2 1/1 1/1 1/1 1/1 111 1/1 1/1 1/1 1/1 1/1 10110 CHI 1/1 0/1 1/1 0/1 1/1 0/1 1/1 0/1 1/1 1/1 6/10 CH2 0/1 Oil 0/1 0/1 Oil Oil 0/1 0/1 0/1 0/1 0110 CH3 0/1 1/1 0/1 1/1 1/1 1/1 1/1 0/1 1/1 0/1 6/10 ESC 1/1 0/1 0/1 1/1 1/1 1/1 1/1 0/1 1/1 1/1 7/10 Phylo 0/1 1/1 1/1 ill 0/1 1/1 Oil 1/1 1/1 1/1 7110 PSO 1/1 0/1 0/1 1/1 1/1 1/1 1/1 1/1 ill 1/1 8/10 Org 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/10 A16 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/10 CU 0/1 0/1 0/1 Oil 0/1 0/1 0/1 0/1 0/1 0/1 0/10 Zn 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/10 Alac 0/1 1/1 1/1 1/1 0/1 1/1 0/1 0/1 1/1 1/1 6/10 Met 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/10 Ben 0/1 0/1 1/1 1/1 0/1 1/1 1/1 1/1 0/1 0/1 5/10 moribund woodlice Example 2

Seven containers for the control and for Multil were set up containing one woodlouse each. A blank pellet containing no metal complexone was used as a control. The species of woodlouse was Armadillidium vulgare. After five days, the number of dead woodlice in each group of containers was determined. The results are shown in Table 2.

Table 2 Number of woodlice dead after 5 days in the different treatments Armadillidium vulgare Treatment #1 #2 #3 #4 #5 #6 #7 Total Control 0/1 0/1 0/1 0/1 0/1 0/1 0/1 on multi] 1/1 1/1 1/1 1/1 1/1 111 1/1 7n Sumnary of the Results Comparing the results for the formulations, Multil, Multi2 and Multi3, indicates that there appears to be little difference in the killing power of the oxo-dimer of ferric EDTA over the concentration range of 4.5% to 9% and the influence of pellet hardness is, in this case, not of paramount importance.

The kill rate for PSO, an experimental formulation containing surfactant and just 1% of ferric ethylenediaminetetraacetic acid, is surprisingly high. Whether this kill rate is due to the addition of sodium dodecyl sulphate as a synergist (see Young, C.L., in W099/25194 entitled: "Improved Stomach-action Molluscicides") is not clear, but our studies on snails indicates that this formulation gives only low kill rates for snails, which is evidence that snails and woodlice have significantly different physiologies and require entirely different treatment regimes.

The surfactant ALKANATE CS' (calcium dodecylbenzene sulphonate) does not appear to be toxic to woodlice. Although this surfactant is not toxic to the common garden snail, Helix aspersa, it appears to be synergistic when mixed with metaldehyde (Bowen, I.D. and Wyn Jones, G., "Molluscicidal Composition in Pellet Form from a Molluscicide and Surfactant" GB Patent No. 2 0 98 8 69/8 1).

Comparing the results for the various chelates, i.e. Multil (ethylenediaminetetraacetic acid iron oxo-dimer), CH1 (hydroxyethylenediaminetriacetic acid ferric salt), CH2 (ethylenediaminebis[(2-hydroxyphenyl)acetic acid) ferric sodium salt), CH3 (diethylenetriaminopentaacetic acid ferric sodium salt), all three of which are metal complexones, and Org ([iroli(III)-3-hydroxy-2-methyl-4pyronel complex), which is not a metal complexone, indicates that the killing power is very dependent on which particular iron chelate is used and that metal complexones are particularly efficacious.

The inclusion of sodium phytate in the bait seems to have a considerably less dramatic effect on toxicity to woodlice compared with studies on snails (Young, C.L., unpublished results). This may be due to the fact that woodlice recycle their faeces (Sutton, (1972)). Conceivably, the phytate locks up the ferric EDTA, but the iron phytate is broken down in the faeces and when re-eaten a significant proportion of the ferric ions are available for absorption from the recycled faeces which then acts as a poison.

The relative toxicity of zinc, copper and iron EDTA to woodlice is significantly different. Although zinc EDTA is much less toxic than iron EDTA or the oxo-dimer of ferric EDTA, the copper EDTA pesticide composition gave zero kill rate for woodlice. This may be due to the unusual way in which copper is stored in the hepatopancreas of woodlice.

Ferric orthophosphate and ferrous sulphate appear to be of low toxicity to woodlice. Ferric orthophosphate has a very low solubility in water and might well be expected to pass straight through the digestive system. Ferrous sulphate, on the other hand, is quite soluble in water; however, it appears either that woodlice are repelled by ferrous sulphate or ferrous sulphate is-made unavailable by natural chelators, such as phytates and sugars, from the flour. The fact that ESCARGO!O' is moderately toxic to woodlice may indicate that some of the additives in the inert carrier are either toxic to woodlice or in some way interfere with the uptake of iron by natural chelators. Metaldehyde has on occasions been claimed to be active against woodlice. Whilst certainly not an exhaustive study, the results in Table 2 indicate that this is not the case with the metaldehyde composition used in this s,tudy.

Methiocarb and bendiocarb are toxic to woodlice although bendiocarb as a talc-based pesticide composition, i.e.

in powder form, is not a very effective killer. These compounds are anticholinesterase agents and are toxic to a wide range of animals.

The results of this study clearly show that the hydroxy- metal complexone derivative of Fe(III)EDTA, [Fe(III)(OH)EDTA]2-, is the most effective of the formulations tested and even more effective than the most effective of the toxic alternative, BAYSOLO 2.0% methiocarb in a grain-based bait.

Example 3

Twelve identical black plastic caps of 4 mm diameter were divided into two groups of six. Six, which formed the control group, were lightly coated with a thin layer of 1% aqueous solution of TERRA CONTROL', a polyvinyl acetate-based binder. The other six were coated with a solution containing 0.7 % TERRA CONTROLO, 1.5% ferric sodium EDTA and 25% flour made up with water in an aqueous paste. Each of the twelve caps were dried and placed in a 1 litre container into which 150 ml of moist pine-based potting mix has been spread. Three woodlice were placed in each container which was then closed with a lid, which had about six small holes in it. The containers were kept at room temperature. After 48 hours, the number of dead and moribund woodlice were counted. A woodlouse was deemed moribund if there was noticeable movement on prodding with a fine metal rod, but the woodlouse did not move more than 5 mm over a period of 1 minute. The results after 48 hours are given in Table 3. The numbers in parenthesis represent moribund woodlice.

Table 3 Number of woodlice dead after 2 days in the different treatments Porcellio scaber Treatment #1 #2 #3 #4 #5 #6 Total Control 0/3 0/3 013 0/3 0/3 0/3 0/18 Treated 2/3 1(2)/3 2(1)/3 2(1)/3 2/3 3/3 12(4)/18 Summary of Results

The above results show that ferric sodium EDTA in a flour-based paste is an effective way of controlling woodlice.

Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications. The invention also includes all of the steps, features, compositions and compounds referred to or indicated in this specification (unless specifically excluded) individually, or collectively, and any and all combinations of any two or more of said steps or features.

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Claims

1. A pesticide composition for woodlice, comprising an effective amount of a metal complexone and a carrier therefor.

2. A pesticide composition according to claim 1, wherein the metal of the metal complexone is selected from aluminium or iron.

3. A pesticide composition according to claim 2, wherein the metal is iron(III).

4. A pesticide composition according to any one of claims 1 to 3, wherein the complexone of the metal complexone is selected from ethylenediaminetetraacetic acid and ethylenediaminedisuccinic acid.

S. A pesticide composition according to any one of claims 1 to 4, wherein the metal complexone is selected from Fe(III)EDTA and the hydroxy derivative of Fe(III)EDTA, [Fe(III)(OH)EDTA 12-.

6. A pesticide composition according to any one of claims 1 to 5, wherein the amount of metal complexone is at least 4.5% by weight of the total composition.

7. A pesticide composition according to any one of claims 1 to 5, wherein the amount of metal complexone is in the range of 4.5% to 12% by weigh t of the total composition.

8. A pesticide composition according to any one of claims 5 to 7, wherein the metal complexone is 2- [Fe (III) (OH) EDTAI

9. A pesticide composition according to claim 8, wherein the amount of [Fe(III)(OH)EDTA]I- is 6% by weight of the total composition.

10. A pesticide composition according to any one of the preceding claims wherein said carrier comprises a nutrient.

11. A pesticide composition according to any one of the preceding claims, wherein the carrier comprises a cereal, wheat.'flour, corn flour, bran, arrowroot, rice flour, carrot, beer, rice hulls, comminuted cuttlefish, starch, gelatin, pumice, carbon, a phagostimulant, a lubricant, a flavouring agent, a preservative or a waterproofing agent, or mixtures thereof.

12. A pesticide composition according to claim 11, wherein the waterproofing agent is selected from a fatty acid alcohol and guar gum.

13. A pesticide composition according to any one of the preceding claims, further comprising a filler.

14. A pesticide composition according to claim 13, wherein the filler is selected from the group of alkali metal and alkaline earth metal carbonates.

15. A pesticide composition according to claim 14, wherein the filler is selected from calcium carbonate and potassium carbonate.

16. A pesticide composition according to any one of claims 13 to 15, wherein the filler is present in an amount in the range of 1% to 5% by weight of the total composition.

17. A pesticide composition according to claim 16, wherein the filler is calcium carbonate present in an amount in the range of 2% to 3% by weight of the total composition. 5

18. A pesticide composition according to any one of claims 13 to 17, wherein the pesticide composition is non-acidic.

19. A pesticide composition according to any one of the preceding clai, tns which is non-phytotoxic and noninsecticidal.

20. A pesticide composition according to any one of the preceding claims, further comprising a surfactant.

21. A pesticide composition according to claim 20, wherein the surfactant is sodium dodecyl sulphate.

22. A pesticide composition according to claim 21, wherein sodium dodecyl sulphate is present in an amount between about 0.2% and 0.3% by weight of the total composition.

23. A pesticide composition according to any one of the preceding claims, wherein the metal complexone is present in combination with at least one other pesticide.

24. A pesticide composition according to claim 23, wherein the other pesticide is selected from methiocarb, bendiocarb and diazinon.

25. A pesticide composition according to any one of the preceding claims, in a solid bait form.

26. A pesticide composition according to claim 25, in tablet, powder, granule or pellet form.

27. A coating formulation for consumption by woodlice, comprising an effective amount of a metal complexone and a suitable carrier therefor.

28. A coating formulation according to claim 27, wherein the carrier comprises an edible binder having a glue-like consistency.

29. A coating formulation according to either of claims 27 and 28, wherein the carrier comprises an edible binder selected from a polyvinyl- acetate based binder, gum arabic and gum acacia.

30. A coating formulation according to claim 29, wherein the binder is a polyvinyl-acetate based binder.

31. A method for the preparation of pesticidal pellets comprising the steps of:

(i) blending a metal complexone and a carrier together to form a blended composition; (ii) heating the blended composition for a time between about 1 to 5 minutes in the presence of steam at an ambient temperature in the range between about 80'C and 100C; (iii) maintaining the composition at the ambient temperature between about 10 and seconds; and (iv) forming the blended composition into one or more pellets.

32. A method according to claim 31,, wherein step (ii) is carried out at about 90'C for about 2 minutes and wherein step (iii) is carried out for about 15 seconds.

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33. Use of a metal complexone as a pesticide for woodlice in a pesticide composition.

34. Use as claimed in claim 33 wherein said composition is a composition as claimed in any one of claims 1 to 26 or a coating formulation as claimed in any one of claims 27 to 30.

35. A method of pesticidal treatment to combat woodlouse infestation of an area which method comprises applying to at,'least part of said area a pesticide composition as claimed in any one of claims 1 to 26 or a coating formulation as claimed in any one of claims 27 to 30.

36. A pesticide composition according to any one of claims 1 to 26 substantially as hereinbefore described with reference to any one of the accompanying examples.

37. Use of the pesticide composition according to any one of claims 1 to 26 substantially as hereinbefore described.

38. A coating formulation according to any one of claims 27 to 30 substantially as hereinbefore described with reference to the accompanying example.

39. Use of the coating formulation according to any one of claims 27 to 30 substantially as hereinbefore described.

40. Use of the method according to claim 31 or claim 32 substantially as hereinbefore described.