AU715946B2 - Olfactory repellent substance and method for protecting plants - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicants: RURAL INDUSTRIES RESEARCH AND DEVELOPMENT

CORPORATION

EGG INDUSTRY COOPERATIVE LTD A.C.N. 059 563 030 THE SECRETARY TO THE DEPARTMENT OF NATURAL RESOURCES AND ENVIRONMENT Invention Title: OLFACTORY REPELLENT SUBSTANCE AND METHOD FOR PROTECTING PLANTS The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 OLFACTORY REPELLENT SUBSTANCE AND METHOD FOR PROTECTING

PLANTS

This invention relates to methods and compounds for repelling browsing animals from plants, and in particular but not limited to a method and compound for repelling rabbits from tree seedlings.

Damage caused by browsing animals to trees is a world-wide concern to the forest industry and land-holders attempting to propagate trees on private land for soil stabilisation, wind-breaks, stock shelter, salinity mitigation, orchards or land re-forestation. Twenty percent of all plantation failures are directly attributed to the action of such "browsing mammals" in the US states of Oregon and Washington. In the Yarram area of Victoria, browsing 15 animals have been implicated in plantation losses of up to 19%.

Where European rabbits (Oryctolagus cuniculus) occur within or on the margins of plantations, they can severely damage both seedlings of eucalyptus and Pinus radiata by a process 20 of defoliation of leaves, bark-stripping or partial or complete removal of woody tissue. In addition, they are known to damage larger seedlings and saplings by the gnawing or stripping of bark. Seedling damage by rabbits will quite often result in the total removal of the S 25 seedling or its death. Such damage to Pinus radiata seedlings has been observed in New Zealand plantations.

Damage to Tasmanian timbers by rabbits has also been observed. Other Lagomorphs, such as the snowshoe hare (Lepus americanus) also impose high levels of browsing damage upon trees and shrubs which retard regrowth of coniferous forest.

Browsing animals in Victorian plantations were until recent years predominantly managed by the use of poison baiting 3 with 1080 (fluoroacetic acid) treated carrots, delivered either by aerial baiting or trail baiting. Growing concern about the target specificity of such techniques prompted an investigation of alternative methods of browsing animal mitigation, which led to the current invention.

Repellents containing an olfactory aversion agent are well known. In the case of rabbits, egg products such as powdered egg have been known to deter rabbits from eating plants. The egg product is mixed with an adherent such as paint or other synthetic products such as "Rhoplex" and applied to the plant by spraying, dipping or painting.

Controlled studies by the inventors of the current application confirm that repellents based solely on egg products offer some repellent effect against rabbits. The :a constituent of the egg, either fatty acids or proteinaceous substances.

It is an object of the current invention to provide a cheap repellent with improved repelling properties, particularly to rabbits, and a method of use of same.

25 Therefore in accordance with a first broad aspect of the invention there is provided a method of repelling browsing animals from plants comprising applying a repellent consisting of or including petroleum jelly as a repelling "agent to the plant or to a surface near the plant.

It has been discovered that petroleum jelly has a strong and persistent olfactory repellent effect on many browsing animals, particularly rabbits.

Preferably, the repellent contains a thinning agent to assist in application of the repellent to the plant or surface. The thinning agent may be a vegetable oil. If the browsing animals are lagomorphs, the vegetable oil may be H:\ARymer\Keep\Speci\Andrew\70530.96.1.doc 7/12/99 4 canola oil.

Preferably also, the repellent further comprises egg powder.

On plants which do not exhibit a phytotoxic reaction to the treatment, the preferred application of the repellent is directly to the plant, using dipping, painting or hand application.

On plants which do exhibit a phytotoxic reaction, the preferred application is to a nearby surface such as a stake, preferably disposed 2-10 centimetres from the plant.

In accordance with a second broad aspect of the invention there is provided an olfactory repellent for protecting plants from browsing animals, comprising petroleum jelly and a thinning agent. Preferred constituents of the repellent can be ascertained from the above defined preferred features of the first aspect.

.9* In order that the invention can be more clearly 9 ascertained, a non-limiting example of a preferred embodiment will now be described.

*99 A batch of the preferred repellent, referred to hereinafter as "AD-3" comprises: 33 kg Vaseline T brand petroleum jelly 66 kg raw canola oil 10 kg egg powder It has been found in controlled studies that the petroleum jelly has a strong and persistent repellent effect and also acts as an adherent which promotes sticking of the compound to the treated surface. The raw canola oil has a pronounced repellent effect on its own and also serves to thin the compound sufficiently to enable dipping or smearing by H:\ARmer\Keep\Speci\Andrew\70530.96.1.doc 22/07/99 5 hand. The egg powder is, as discussed above, a known olfactory repellent.

Experiments have shown that the repellent of the preferred embodiment (AD-3) is effective against rabbits, and may be applied directly to Pinus radiata and Pinus pinasta seedlings without phytotoxic reaction. For cherry tree root stock, and seedlings of eucalyptus, casuarina and leptosperms, a phytotoxic reaction prevents direct application, but these plants may be effectively protected by application of the repellent to a stake driven into the ground beside the plant, about 2-10 cm away.

The canola oil is not expected to be a repellent for all browsing animals. It is a common feature of olfactory repellents that they are effective only on certain species.

15 Consequently the effectiveness of the repellent must be judged in specific cases. In particular, it has also been found that wallabies are attracted to rather repelled by the canola oil component. Although the repellent has been tested only for rabbits and wallabies, it may be expected that it is effective for a wider class of browsing animals than rabbits alone.

Field trials were conducted by the current inventors to assess the effectiveness of AD-3 in comparison with other repellents and with untreated controls.

Figure 1 shows test results where AD-3 was applied directly to cherry tree seedlings which were planted in a rabbit enclosure. There were a total of 50 treated seedlings and untreated seedlings. For the treated seedlings, the figure shows that there was no damage after day 23, whereas all of the untreated seedlings had been damaged. Further observation revealed that the treated seedlings remained undamaged up to day 60. At day 73, minor rabbit damage was noticed. It was also noted that the AD-3 unfortunately had 6 a toxic effect on the seedlings which was by day 73 becoming apparent. Subsequent experiments were performed by dipping a stake in AD-3 and planting the stake 2-10 cm from the seedling. This resulted in an improved repellent effect over direct application, since more repellent could be applied, and no toxic side effect on the plant.

Figure 2 shows the result of applying a range of treatments to Eucalyptus regnans seedlings in a wallaby enclosure.

WR-

1 is a repellent which has a masticatory aversive agent as an active ingredient and does not embody the current invention. WR-1 has been described in a co-pending Australian application, also in the name of the current applicants. Figure 2 shows that egg and paint, which is a known repellent to rabbits, is ineffective against wallabies, and that AD-3 is actually an attractant. Further studies have shown that it is the canola oil component which attracts the wallabies.

Figure 3 demonstrates the effectiveness of AD-3 in repelling rabbits from pine seedlings. In the case of 20 pines, AD-3 can be applied directly by hand to the plant without toxic side effects.

Further experiments have shown that 1. the petroleum jelly component of AD-3 has the strongest and most persistent repellent effect on rabbits; 25 2. the canola oil is somewhat repellent, and helps to thin the petroleum jelly for easy application and to produce a cheaper compound; 3. raw canola oil has the strongest enhanced repellent effect, but both bleached and deodorised canola oil also have a positive effect; 4. if other oils are substituted for canola oil, a useful repellent results but it is not as effective as AD-3; the egg powder produces a beneficial initial 7 boost to the total repellent effect, but its contribution wears off faster than the petroleum jelly.

Modifications can be made to the invention as would be apparent to a person skilled in the art of repellent design. These and other modifications may be made without departing from the ambit of the invention, the nature of which is to be ascertained from the foregoing description and the figures.

Claims (15)

1. A method of repelling browsing animals from plants comprising applying a repellent consisting of or including petroleum jelly as a repelling agent to the plant or to a surface near the plant.

2. A method as claimed in claim 1, wherein said browsing animals are lagomorphs.

3. A method as claimed in claim 1, wherein said browsing animals are macropods.

4. A method as claimed in any one of the preceding claims, wherein said repellent contains a thinning agent to assist in application of said repellent to the plant or surface.

5. A method as claimed in claim 4, wherein the thinning agent is a vegetable oil.

6. A method as claimed in claim 5, wherein said browsing animals are selected from the group consisting of lagomorphs and the vegetable oil is canola oil. S 25

7. A method as claimed in any one of the preceding claims, S* wherein the repellent further comprises egg powder.

8. A method as claimed in any one of the preceding claims, wherein the application of the repellent is directly to the plant, using dipping, painting or hand application.

9. A method as claimed in any one of claims 1 to 6, wherein the application of the repellent is to a surface disposed near the plant. A method as claimed in claim 9, wherein the surface is 2-10 centimetres from the plant.

H:\ARymer\Kee\Speci\Andrew\753096.1doc 7/12/99 9-

11. An olfactory repellent for protecting plants from browsing animals, comprising petroleum jelly and a thinning agent.

12. An olfactory repellent as claimed in claim 11, wherein said browsing animals are selected from the group consisting of macropods and lagomorphs.

13. An olfactory repellent as claimed in claim 12, wherein said browsing animals are selected from the group consisting of lagomorphs and said repellent comprises approximately: 33% by weight petroleum jelly, 66% by weight raw canola oil, and 10% by weight egg powder. *I.

14. A method of repelling browsing animals from plants substantially as hereinbefore described.

15. An olfactory repellent for protecting plants from browsing animals substantially as hereinbefore described. Dated this 22nd day of July 1999 25 RURAL INDUSTRIES RESEARCH AND DEVELOPMENT CORPORATION, EGG INDUSTRY COOPERATIVE LIMITED and S" THE SECRETARY TO THE DEPARTMENT OF NATURAL RESOURCES AND ENVIRONMENT By their Patent Attorneys GRIFFITH HACK Fellows of the Institute of Patent and Trade Mark Attorneys of Australia l-\ARymer\Kep\Speci\Andrew\ 70 5

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