GB2484989A - Plant guard having means to release chemical compositions - Google Patents

Abstract

A plant guard 1 is formed of a physical barrier the barrier being associated with means to release chemical compositions, such as insecticides, fertilisers, mycorrhizae etc.. The physical barrier may be a tubular structure 2 having at least one open end 3 that may be positioned around a plant stem or tree trunk. The tubular structure may be an elongate tube with inner 4 and outer 5 walls with a space between the walls. Inserts 6 may be positioned in the space between the inner and outer walls, the insert forming one or more containers in which the chemical composition may be held. The plant guard may be expandable and made of stretchy material or concertina type structure. The plant guard may include a pest monitoring tool or indicators to provide information about the guard. The guard may be formed of a biodegradable material.

Description

Plant Guard The present invention relates to a plant guard and in particular but not exclusively to a multifunctional guard that can be used with a range of plants, such as trees.

Traditional tree or plant guards are typically physical barriers to grazers/browsers. They also provide some shelter to young plants to help them establish, however, known tree guards simply perform one function, for example, by providing a physical barrier to pests.

Known guards do not provide several functions where pests such as insects may be repelled at various stages in the life cycle of that pest. Furthermore, most guards protect the plant above ground and no guard is designed to protect the subterranean parts of the plant.

Existing guards are typically made of thermoplastic materials which provide a physical barrier to grazing/browsing animals and to a lesser extent insect attack. The tree guards are typically made of heavy durable plastic sheet, mesh, netting or non-woven blankets and held in position with stakes or the like. More recently, the guards have incorporated biodegradable materials such as starch. However such guards typically are not totally degradable which means that as a plant grows the guard may compress the plant, which can stunt growth or even damage the plant, leading to susceptibility to disease. Also known physical barriers that are not degradable become unsightly in the environment and furthermore, due to the lack of safe degradability, residues of material may leach into the environment which raises toxicity issues.

The present invention seeks to overcome the problems associated with the prior art by providing a plant guard that can perform several functions.

According to the present invention there is provided a plant guard formed of a physical barrier said physical barrier also being associated with release means to release chemical compositions.

In a preferred embodiment the physical barrier is provided by a tubular structure having inner and outer walls with a spacing between the inner and outer walls into which an insert may be placed, which includes containers for the chemical compositions.

Alternatively, the release means to release chemical compositions is provided by a series of channels formed on the surface of the tubular structure. This means the dispenser is integral with the tubular dispenser, rather than being a separate liner.

Chemical compositions that can be released include useful materials such as mycorrhizae, fertilizers, and plant protection agents. Furthermore chemicals that repel pests (chemical barrier) may be released. The chemical repellents are typically, deer repellents, rodent repellents such as vole or mouse or insect repellents.

Preferably there is a plurality of release means. It is envisaged that each of the channels or containers may contain the same chemical composition or the containers may contain different chemical compositions. The compositions may be for example a range of insecticides for different pests of there may be a combination of insecticides in some containers, repellents in others and growth promoters in other containers. As an alternative or in addition, the chemicals may affect pests at different stages in their life cycles, so providing a means to control pests at all stages in their development. The plant guard of the present invention has a multifunctional role, more specifically, besides being a physical barrier and shelter the plant guard will also act as a chemical barrier to pests.

It is envisaged that the release means includes products useful to the well being of the plant such as fertilizers, plant protection products, mycorrhizae etc. More preferably the plant guard includes a pest monitoring tool. The pest monitoring tool may be an adhesive onto which a pest lands and is secured in place or a jar into which a pest falls. The adhesive may be provided in the form of a coating that typically traps arthropod pest species that can be then be monitored.

It is also envisaged that the tree guard has feet that can be inserted in the ground. The feet can also have dispensers that release material into the ground around the roots of the plant. The release of materials into the ground will provide protection against subterranean pests and diseases which is not accomplished with traditional tree guards.

It is envisaged that the structure has indicator strips/colours to be used to determine features about the structure, such as the shelf life of product, for example how close is to degradation or the exhaustion of the release material and such a feature provides and element of quality control to the product.

Furthermore it is preferred that the plant guard is formed of a biodegradable material.

The tubular structure having inserts/tubes allows for the easy insert of tubes for release of behaviour modifying chemicals, mycorrhizae, fertilizers, plant protection products. Also the chemicals may be incorporated into gel which is injected into tubular dispensing chambers to slowly release behaviour modifying chemicals, plant nutrients, or plant protection products.

If a single layer is used to form the tubular structure, there are at least two variants, the first being a guard that has folds between pockets/inserts that unfold to accommodate tree or to expand with the tree as it grows. Also the guard may be made of a stretchable material between pockets/inserts to stretch as the tree grows.

Items for dispensing or for use with guards include plant protection products, for example, synthetic or natural products (botanicals, biological control agents etc) that have insecticidal, acaricidal, nematicidal, herbicidal, fungicidal or bactericidal activity. These will include biological control agents (BCAs) that work synergistically with botanicals and synthetic chemicals used at extremely low rates. BCAs are designed to kill subterranean pests (e.g. chafers, vine weevil, leatherjackets) or pests on tree trunk/stems -(e.g. woolly aphids) or they also include agents that are antagonistic to disease agents Other materials that can be dispensed include semiochemicals which are any behaviour modifying chemicals that deter, confuse, scare, repel, or attract animals whether they are mammals or arthropods. Examples include predator scents, alarm pheromones, non-host volatiles etc. Attractants include compounds that lure in pests to a control agent, compounds that lure in pest to a non-host plant or compounds that lure in beneficial predators and parasitoids. Other behaviour modifying compounds include deterrents, which includes compounds that prevent pests becoming established (e.g. sticky traps/strips), compounds that repel pests (e.g. alarm pheromone, predator scent) or compounds that deter pests (e.g. bitter tasting compounds).

Another group of materials that can be used include mycorrhizae, which are fungi which enhance plant growth via symbiotic associations with the host plant Other plant growth enhancing products include organic and inorganic fertilizers, bio fertilizers e.g. bacteria or fungi which stimulate plant growth directly or via release of nutrients which were not accessible to the plant.

Bio fertilisers may be described as plant growth stimulants or agents that enhance plant growth (e.g. rhizobacteria, Trichoderma, Gliocladium, mycorrhizae) The invention will now be described by way of example only with reference to and as illustrated in the accompanying figures in which: Figure 1: shows a guard according to a first embodiment of the invention; Figure 2: shows a guard according to a second embodiment of the invention including dispensing tubes or inserts; Figure 3: shows a guard according to a further embodiment of the invention which is a stretchable structure; Figure 4: shows a guard according to an embodiment of the invention when in use.

As shown in Figure la, the plant guard generally shown as I is formed of a tubular structure 2 having at least one open end 3. The tubular structure as shown in Figure 1 b has inner wall 4 and outer wall 5. Inserted between the wall layers are dispensing tubes/inserts 6 which dispense nutrients, plant protection products or behaviour modifying chemicals. An inner lining 7 of the tube is coated with sticky material that traps ticks and other arthropod pests. The sticky material may be a glue or adhesive which may incorporate semiochemicals. The use of a liner has the benefit that an operator that is installing the plant guard is unlikely to be exposed to the glue but there is also the combined benefit of the fact that insects may also get trapped.

As can be seen there is a series of channels or chambers 6 situated around the periphery of the liner and these can receive materials such as insecticides. The channels or chambers may each have the same compound or they may have different compounds. If there are different compounds, then different pests may be treated or it may be that some of the chambers/channels have insecticides while others have growth promoters for the plant. The chambers can be charged or re-charged as desired by injecting gel or insert containing the appropriate semiochemicals, plant protection products, fertilisers (plant nutrients) etc. Other materials that can be used include volatiles that confuse pests e.g. isothiocyanates attract crucifer pests but when emitted from confiders that release terpenoids would confuse conifer pests or volatiles that repel pests, for example bio fumigants. Further materials that can be used include volatiles that attract beneficial insects e.g. farnesenes that are aphid alarm pheromones but attract predators and parasitoids.

The guard may also have a series of feet or anchors (not shown) around its lower surface that help anchor tree guard to ground but which also can deliver chemicals to the roots of the plant.

Figure 2a shows a plant guard formed of a tubular structure with porous outer 8 and inner walls 9. As shown in Figure 2b, inserted between the wall layers are dispensing tubes or inserts 6 which dispense primarily behaviour modifying chemicals but could dispense mycorrhizae, nutrients and plant protecting agents. The walls are provided as two interlocked corrugated or smooth porous tubes with dispensing sections or tubes. Whole apparatus dispenses desired semiochemicals -these could deter arthropod pests or "scare" rodents or deer. Such repellents may be based on alarm pheromones or scents of predators or territorial markings. Different channels in tube dispense different compounds in the desired direction. Furthermore there are feet that anchor the plant guard to the ground and these anchors have can deliver materials to the root zone via "feet" that are formed integral with the anchors or which are in proximity to the anchors.

Figure 3a shows a plant guard which consists of a stretchable structure generally shown as with pre-moulded insert 11, for example receptacles or pockets for inserts. The stretchable structure provides a sheath or corset. The plant guard is formed of an extendable tube with insertions for dispensing behaviour modifying chemicals as shown in Figure 3b. The guard can be used as a protective sleeve around a plant and has the advantage that it will expand with an expanding tree/branch. The material between insert pockets stretches or unfolds as shown as 12 and where concertina like folds 13 are present this also allows for tree expansion but offers greater stability.

Figure 4 shows a plant guard I according to an embodiment of the invention in use. The guard is positioned around the main stem of a plant, or trunk 14 in the case of a tree. The guard protects against vermin such as deer, rabbits, voles, mice. The fact that the plant is physically protected encourages good plant growth and reduces the risk of having to replace plant which can be costly, certainly with valuable plants. The guard also have environmental benefits to enhance biodiversity by providing nests for beneficial animals.

When the plant is encased by a physical barrier and there is a space 15 between the plant and the barrier this also creates a greenhouse effect and can protect against high temperatures in sun and low temperatures in winter, so avoiding the risk of a frost pocket forming around the roots of a plant. By maintaining a good environment around a plant root, this helps prevent against diseases such as sudden oak death or the rotting of roots 16.

The use of traps with the plant guard also contributes to a safer environment by providing a physical trap to insects such as ticks and midges. The guard may also trap arthropods/fungal spores which allows for the monitoring of pests and diseases.

Typically the chemicals that are released slowly and they include behaviour modifying chemicals to lure and kill or repel pests. An example of the chemicals includes Isothiocyanates, which occur naturally as glucosinolate conjugates in cruciferous vegetables. They attract crucifer specialist insects e.g. pollen beetle, seed weevil. They would confuse conifer specialists which often respond to conifer chemicals such as terpenoids. Chemicals can be used that act as bio fumigants at the space around a tree trunk and these deter pests. Fumigants with antimicrobial properties will protect against disease agents. Dispensing methods include: leaching (rain guides), shaking by wind, slow drip etc.

S

The present invention relates to the design and construction of a guard that protects trees and other plants used in the horticultural, forestry, bio fuel crops, amenity, and allied sectors. An extension of the invention further relates to the incorporation of additive materials that enhance the protection of the plant from microbial plant pathogens, invertebrates (e.g. insects, nematodes, slugs) and animal attack (mostly deer, voles and mice). The guard is designed to provide protection above ground but also some protection below ground i.e. to roots. It also has additional benefits such as slowly releasing nutrients and limiting/preventing establishment of disease vectors (e.g. ticks, midges) which pose a threat to human and animal health especially in less accessible or infrequently used terrains (forests) or habitats often used by tourists (parks or woodlands). The guard could also be adapted to monitor certain pest species such as ticks which are vectors of zoonotic diseases and are particularly abundant in forest habitats.

The multifunctional tree guard would be ergonomic, cost effective and appropriate for all kinds of habitats or terrains especially forest habitats which are often inaccessible, occasionally inhospitable and requiring low maintenance costs.

The ideal guard should provide a function comparable to existing non degradable products during the service life and then biodegrade with no residual toxicological effect to the soil.

Typically the plant guards of the present invention would be useful in plantations, sites for bio fuel crops e.g. where willow, poplar etc is grown, forests/woodlands, vineyards, fruit farms, horticultural establishments and the home and garden markets. ln particular conifers are vulnerable to a wide variety of pests, weeds and diseases and the device of the present invention has particular applications in this area. Typically the device can be used to control: Arthropod pests:

Pest Example Notes

Adelgids Balsam woolly adelgkl Aphids Balsam twig aphid (Mindarus abietinus) Scale insects Pine needle scale (Chionaspis pinifoliae) Beetles pine shoot beetle (TomTcus piniperda), -Longhorn beetles are major longhorn beetles concern in USA and China.

It causes damage but can also transmit pine nematodes Weevils Black vine weevil, White çne weevil -Vine and pine weevils are (Pissodes strobi); Pine root collar weevil of global importance (Hylobius radicis), Moths Gypsy moth (Lyman tria dispar), pine Gypsy moth -big problem in processionary moth, oak procession ary USA -polyphagous. Oak moth processionary moth -emergent pest species Midges Balsam gall midge (Paradiplosis tumifex European pine Neodiprion sertifer Defoliate pines sawfly Mites Spider mites, Erkphyid mites --________________________ Disease agents: -Disease agent Latin name Notes Annolus root rot Heterobasidion annosumor Fomes -________________________ annosus Armillaria root rot Armillaria ostoyae, formerly A. me/lea Sudden oak death Phytophthora ramorum -Attacks wide range of plants -conifers, oaks, rhododendrons Phytophthora root Phytophthora cinnamomi rots Rusts White pine blister rust (Cronartium ribicola; fir-fern rusts (Uredinopsis sp., I0 Miasma sp:); pine-pine gall rust (Endocronartium harknessll) Lophodermium Lophodermiumseditiosum needlecast Other potential pests * Ants -can kill trees, protect aphids * Wasps -nests within shelter -damages fruit, nuisance pests * Ticks -serious health risks to humans, pets and wildlife (zoonotic diseases) * Midges -nuisance pests (biting), serious health risks to humans and animals * Nematodes -cause wilt, death (e.g. pine wood nematode = pine wilt nematode -Bursaphe/enchus xylophilis) It will be appreciated by the persons skilled in the art that the above embodiment has been described by way of example only, and not in any limitative sense, and that various alterations and modifications are possible without departure from the scope of the invention as defined by the appended claims.

Furthermore, it is to be understood that although individual embodiments of the invention are discussed the invention also covers a combination of any of the individual embodiments.

Claims (18)

1. Claims 1. A plant guard formed of a physical barrier said physical barrier also being associated with release means to release chemical compositions.
2. 2. A plant guard according to claim 1, wherein the physical barrier is provided by a tubular structure that is positioned around the periphery of a plant stem or tree trunk.
3. 3. A plant guard according to claim I or claim 2, wherein the tubular structure is provided by an elongate tube having inner and outer walls with a space between the inner and outer walls.
4. 4. A plant guard according to claim 3 wherein one or more insert can be positioned in the space between the inner and outer walls.
5. 5. A plant guard according to claim 4, wherein the insert includes one or more containers for the chemical compositions.
6. 6. A plant guard according to claim 5, wherein the containers are formed of tubes or channels passing along at least part of the length on the insert.
7. 7. A plant guard according to claim 1 or claim 2, wherein one or more tubes or channels are attached along the length of the physical structure in which a chemical composition can be held.
8. 8. A plant guard according to claim 7, wherein the physical structure is formed of a wall that is expandable.
9. 9. A plant guard according to claim 8, wherein the wall is formed of a stretchable material.
10. 1O.A plant guard according to claim 7, wherein the wall is a concertina type structure.
11. 11.A plant guard according to any preceding claim wherein the release means is provided by a gel that can hold the chemical composition and slow release the chemical composition over a period of time.
12. 12.A plant guard according to any preceding claim including a pest monitoring tool.
13. 13. A plant guard according to claim 9, wherein the pest monitoring tool is an adhesive surface.
14. 14.A plant guard according to any preceding claim including indicators to provide information about the plant guard.
15. 15.A plant guard according to any preceding claim having feet at the base of the guard which can secure the guard in place but which also has dispensing means to release composition to the root of a plant around which the plant guard is positioned.
16. 16. A plant guard according to any preceding claim wherein the plant guard is formed of a biodegradable material.
17. 17. A plant in combination with a plant guard according to any preceding claim.
18. 18. A plant guard according as substantially described herein with reference to and as illustrated in the accompanying figures.