Plant support rod and bite-protection kit having such a plant support rod

Abstract

The invention relates to a plant support rod for supporting plants, in particular trees, which is made primarily of a wooden material and is designed to be driven into the ground. The invention provides that the plant support rod is at least partially provided with at least one outer layer made of polymer material, which has a proportion of between (10) wt.% and (100) wt.% of at least one biodegradable polymer. The invention also relates to a bite-protection kit with a plant support rod of the aforementioned type and a grow casing attachable thereto.

Description

[0001] Plant support rod and browsing protection kit with such a plant support rod

[0002] The invention relates to a plant support rod for supporting plants, in particular trees, which is primarily made of a wooden material and designed to be driven into the ground. The invention further relates to a browsing protection kit comprising at least one such plant support rod and at least one growth sleeve that can be attached thereto.

[0003] Plant support rods of the aforementioned type are primarily used in forestry, but also in agriculture, gardening, and landscaping. They are used to support mostly young plants, such as trees, in order to protect them from external influences, such as wind, by tying the plant to the plant support rod or by using the latter as a climbing aid. In addition, plant support rods of this type are used to attach growth sleeves, which are also referred to as browsing protection or sweeping protection and serve to protect plants against animal browsing in order to protect young plants, especially trees, during their growth. Known growth sleeves are usually made of flexible films made of polymer materials, which are wrapped around at least the lower section of the plant, such asthe trunk of a young tree, so that they are given a tubular shape in order to surround at least the lower section of the plant and prevent animals from eating or otherwise damaging the bark or other parts of the plant. Both the growth sleeve and in particular the plant support rod should ideally have a lifespan of at least 3 to 7 years in order to be able to fulfil their function until the plant to be protected has reached a sufficient age at which it has achieved sufficient stability and / or has become insensitive to browsing.

[0004] On the other hand, plant support rods of this type should be made of biodegradable and, preferably, residue-free materials so that they do not have to be removed after the required storage period, particularly in open areas, e.g., in forests, and to ensure that no biologically and / or ecotoxicologically harmful substances are released into the environment. For example, plant support rods made of metallic materials pose a risk of metal compounds being released into the environment. On the other hand, metallic plant support rods pose a risk of injury to (wild) animals, which is particularly true when iron-based plant support rods rust over time.

[0005] In the case of plant support rods made of synthetic polymer materials, a further fundamental problem is the unavoidable release of plastic particles into the environment. This occurs not only through mechanical impact from (wild) animals, but also purely through environmental influences prevailing in forests or nurseries, such as wind, rain, artificial irrigation, and the like. This can, on the one hand, release relatively large fragments of plastic, which pose a danger, particularly to fauna, if animals ingest such plastic particles and the latter accumulate in their digestive systems.On the other hand, so-called "microplastics" can enter the environment. This refers to plastic particles up to 5 mm in size that are created through physical, chemical or biological decomposition as well as through fragmentation of the plastic material of the plant support rod. These particles pose an even greater threat to the environment, as they can accumulate in both fauna and flora. The latter also applies to a variety of environmentally harmful additives in synthetic plastics, which can migrate from the plastic under the ambient conditions typically prevailing in the field and enter the food chain. For example, plasticizer oils can contain polycyclic aromatic hydrocarbons (PAHs), some of which are classified as carcinogenic, mutagenic, and / or toxic to reproduction. Furthermore, PAHs can be persistent, i.e., they remain in the environment for a long time.are poorly degraded. In addition, they are capable of bioaccumulating, i.e., accumulating in the fatty tissue of humans and animals, which makes their health-threatening effects particularly severe. Moreover, microparticles in particular can also have a direct impact on soil organisms and consequently on soil functionality. Among other things, reduced reproduction and shorter body length of nematodes have been observed as a result of the influence of microplastics. Consequently, the use of conventional plastics based on fossil raw materials and the resulting release of long-lasting (micro)plastics into the environment should be prevented as far as possible due to the environmental and health-related consequences for flora and fauna.

[0006] For this reason, plant support stakes of this type are usually made of wood. However, these stakes have the disadvantage that their durability is limited under outdoor environmental conditions, including strong temperature fluctuations, rainfall, and direct sunlight. They also decompose relatively quickly, meaning they are unable to fulfill their intended function for the entire required service life. To ensure the required service life, relatively expensive hardwoods, such as acacia or robinia, are currently used to make plant support stakes. This also proves to be unsustainable, as the raw wood often has to be transported long distances and is frequently obtained by logging in forests without adequate reforestation.

[0007] The invention is therefore based on the object of developing a plant support rod of the type mentioned above in a simple and cost-effective manner so that it has a long service life in the open while at the same time being highly environmentally friendly, while at least largely avoiding the aforementioned disadvantages. It is further directed to a browsing protection kit of the type mentioned above, which comprises at least one such plant support rod.

[0008] According to the invention, this object is achieved in a plant support rod of the type mentioned at the outset in that the plant support rod is at least partially provided with at least one outer layer of a polymer material which has a proportion of between 10 mass % and

[0009] 100 mass % of at least one biodegradable polymer .

[0010] To achieve this object, the invention further provides for a browsing protection kit of the type mentioned at the outset to comprise at least one plant support rod of the aforementioned type.

[0011] The inventive design of the plant support rod with at least one outer layer made of a polymer material forming at least part of its surface, which polymer material has a proportion of between approximately 10% by mass and approximately 100% by mass of at least one biodegradable polymer, protects the wood material of the plant support rod from premature biological degradation, such as rotting under outdoor conditions, so that the plant support rod can fulfil its function over the required period of time without the need to use expensive and ecologically questionable hardwoods, as has been the case up to now.

[0012] Regarding the polymer material of the plant support rod according to the invention, which contains between approximately 10% and approximately 100% by mass of at least one biodegradable polymer, the invention furthermore makes it possible for the polymer material to decompose, after or at least partially during the required service life of the plant support rod, into degradation and / or metabolic products that are both harmless to health and ecotoxicology, leaving virtually no residue. This ensures perfect environmental friendliness without any significant introduction of long-term stable or even ecotoxic microplastic particles. "Biodegradable" within the meaning of the invention means that the at least one polymer of the polymer material can be completely degraded by microorganisms, such as bacteria and fungi, or by enzymes. The microorganisms use the polymer as food or as an energy source.During this metabolism, the polymers must be completely broken down under aerobic conditions into carbon dioxide (CO2), water (H2O), mineral salts and new biomass. Without the supply of oxygen, i.e. under anaerobic conditions, a complete conversion into carbon dioxide, mineral salts, biomass and methane (CH4) must take place. The at least one biodegradable polymer of the polymer material can preferably be compostable in accordance with the standard DIN EN 13432 or the US standard ASTM D6400, whereby composting represents a special case of biodegradability. In industrial composting, the compostable polymer must be completely broken down within a comparatively short period of time of a maximum of two years under controlled conditions (i.e. a temperature of approximately 60°C and a defined humidity).

[0013] In the plant support rod according to the invention, it can advantageously be provided that at least one end section of the plant support rod intended for driving into the ground, which is usually subject to particularly rapid biological degradation processes due to constant contact with the often moist soil, is provided with at least one outer layer made of the polymer material. In many cases, it may be sufficient for only the end section of the plant support rod intended for driving into the ground to be surrounded by such an outer layer, whereas it is of course also possible to provide at least the outer surface of the plant support rod and / or essentially the entire surface of the plant support rod with at least one outer layer made of the polymer material, provided that high protection against biological degradation over a longer service life is required.

[0014] The thickness of the at least one outer layer of polymer material can expediently be at least about 0.1 mm, in particular at least about 0.2 mm, preferably at least about 0.3 mm, e.g., at least about 0.5 mm, in order to provide reliable protection of the wood material of the plant support rod against premature rotting. On the other hand, it is generally sufficient if the thickness of the at least one outer layer of polymer material is at most about 3 mm, in particular at most about 2 mm, preferably at most about 1.5 mm, e.g., at most about 1 mm.

[0015] In an advantageous embodiment, the polymer material of the at least one outer layer of the plant support rod can have a proportion of the at least one biodegradable polymer of at least about 20% by mass, in particular of at least about 30% by mass, preferably of at least about 40% by mass, most preferably of at least about 50% by mass. Particularly preferred are proportions of the at least one biodegradable polymer of at least about 60% by mass, in particular of at least about 70% by mass, preferably of at least about 80% by mass, and most preferably of at least about 90% by mass, wherein the proportion of the at least one biodegradable polymer can also be at least almost 100% by mass.

[0016] In a further advantageous embodiment, it can be provided that at least one biodegradable polymer of the polymer material of the at least one outer layer of the plant support rod is selected from the group of at least partially or preferably also substantially completely bio-based polymers, which are polymers that can be produced completely or partially from renewable raw materials, as explained in more detail below.

[0017] The polymer matrix of the at least one outer layer of the plant support rod should expediently also have a water solubility of at most about 0.5 g / l, e.g. of at most about 0.3 g / l, in particular of at most about 0.1 g / l, so that it is largely insoluble in water and stable under the influence of precipitation, such as rain or snow, over a longer period of time between about 3 and 7 years and does not dissolve. Furthermore, it can be provided that the polymer material of the at least one outer layer of the plant support rod has at least one filler embedded therein. The filler can be essentially powdery, particulate, or fibrous fillers, which in turn should preferably be of natural origin and biodegradable.Examples of possible fillers include, in particular, fibrous, powdered, and particulate natural materials such as cellulose, lignin, wood, reed, miscanthus, hemp, seaweed, nutshells, crushed fruit kernels, and the like, as well as mineral substances such as ash. The natural materials used as fillers - like the polymer material of the outer layer itself - are practically completely biodegradable and therefore neither accumulate over time nor wear down into environmentally harmful micro- or nanoparticles. They are also freely available in large quantities and very inexpensively.In the case of crushed fruit kernels, these can also impart greater hardness to the at least one outer layer of the plant support rod than plant fibers and thus greater resistance to mechanical impact, such as when a (wild) animal rubs against or bites into the plant support rod. Examples of suitable fruit kernels include kernels of olives, cherries, apricots, mirabelle plums, plums, damsons, peaches, nectarines, dates, almonds, coffee berries, mangoes, apples, pears, oranges, grapes, melons, lemons, avocados, papayas, and the like.

[0018] With regard to the at least one biodegradable polymer of the polymer material used for the at least one outer layer of the plant support rod, it can be provided in an advantageous embodiment that at least one biodegradable polymer of this polymer material is selected from the group of thermoplastic polymers, so that on the one hand a simple coating of the wood material of the plant support rod with the at least one outer layer is possible by means of known thermoplastic processing methods (e.g. by means of injection molding, extrusion, deep drawing, hot pressing or the like; see also below), and on the other hand, if required, a simple recycling of the outer layer of the plant support rod is also provided. Advantageous biodegradable polymers include in particular those according to the above-cited standard DIN EN 13432, in particular from the group

[0019] - the polyhydroxyalkanoates, in particular polyhydroxybutyrate (PHB), poly-4-hydroxybutyrate (P4HB), polyhydroxyvalerate (PHV), polyhydroxyacetic acid, poly (3-hydroxybutyrate-co-4-hydroxybutyrate), poly (3-hydroxybutyrate-co-4-hydroxy-butyrate), poly ( 3-hydroxybutyrate-co-4-hydroxybutyrate), polyhydroxyhexanoate (PHH) and / or polyhydroxyoctanoate (PHO);

[0020] - Polylactide (PLA);

[0021] - starch and / or its derivatives;

[0022] - polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS) and / or polybutylene succinate adipate (PBSA);

[0023] - polysaccharides and / or their derivatives;

[0024] - lignin and / or its derivatives;

[0025] - Polycaprolactones (PCL);

[0026] - Proteins and / or their derivatives including their blends.

[0027] The biodegradable polymers can therefore be those that are synthesized from monomers. The biodegradable polymers can, as mentioned above, advantageously be bio-based polymers, such as preferably polylactic acid (PLA), polyhydroxyalkanoates (PHA), e.g. polyhydroxybutyrate (PHB), starch and / or lignin including their derivatives, etc., as well as non-bio-based polymers, such as polybutylene adipate terephthalate (PBAT), polycaprolactones (PCL), etc. Furthermore, the biodegradable polymers can also be partially bio-based, for example in the case of polybutylene succinate (PBS) or polybutylene succinate adipate (PBSA). Examples of polysaccharide derivatives include those in which functional groups of the natural polymer, e.g. the OH and / or NH2 groups, are partially or completely substituted, such as in the case of cellulose esters (e.g.B. cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate etc.), starch esters (such as starch acetate, acetylated distarch adipate etc.) or partially deacetylated chitin and its derivatives.

[0028] In particular, several biodegradable polymers can be used in the form of a blend or polymer mixture, each of which can be bio-based, non-bio-based, and / or partially bio-based. This can also prove advantageous given that some biodegradable polymers are difficult to process on conventional thermoplastic processing machines, such as single- or twin-screw extruders, and / or the properties of the pure polymers alone are unsatisfactory. However, if several polymers are physically blended in the melt to form a blend, starch-PBAT blends or PLA-PBAT blends, for example, can be generated, which are readily processable.In addition to the possible addition of additives, fillers and the like (see below), the advantages of various biodegradable polymers can be combined in this way and any disadvantages, such as the dominant brittleness of a blend partner, can be compensated.

[0029] In addition, with a view to a certain elastic flexibility of the at least one outer layer of the plant support rod, in order to take into account different thermal expansion coefficients compared to the wood material of the plant support rod in the case of the relatively high temperature fluctuations that usually occur in the open air, it can preferably be provided that at least one biodegradable polymer of the polymer material is selected from the group of elastomeric polymers, in particular from the group of natural rubber (e.g. from rubber plants and / or dandelion milk), in order to impart the respectively desired elasticity to the outer layer, wherein the elastomeric polymers can in particular be mixed with one or more of the above-mentioned thermoplastic polymers in order to set the desired elasticity.Furthermore, a covalent integration of a soft phase into the at least one biodegradable polymer of the at least one outer layer of the plant support rod is also conceivable in order to adjust the resilient, elastic properties. Examples of such a soft phase include the integration of low-molecular-weight polyethylene glycols (PEGs), which are biodegradable up to an average molecular weight of approximately 1,500 g / mol.

[0030] The polymer material of the at least one outer layer of the plant support rod should, moreover, have a melting point of at least 70 ° C, in particular of at least 80 ° C, preferably of at least 90 ° C, e.g. of at least about 100 ° C, in order to prevent the outer layer from partially or completely melting or even being chemically degraded, even at very high ambient temperatures and / or direct sunlight.

[0031] The at least one outer layer can in principle be applied in any known manner to the wood material of a base body of the plant support rod made of wood material. If the polymer material of the outer layer is a thermoplastic polymer material, it can be provided, for example, that the at least one outer layer is formed by at least partially immersing such a base body of the plant support rod made of wood material into the plasticized thermoplastic polymer material of the at least one outer layer and solidifying the polymer material. However, it is also conceivable, for example, that the at least one outer layer is formed by at least partially immersing the base body of the plant support rod made of wood material into a resin mixture and curing the resin mixture to form the polymer material of the outer layer. In the latter case, the resin mixture can, for example,Mono-, di- and / or oligomers and optionally catalysts, initiators and the like in order to convert them into a thermoplastic or thermosetting polymer to form the outer layer.

[0032] Instead, it can also be provided, for example, that the at least one outer layer is formed by extruding the thermoplastic polymer material of the at least one outer layer onto a base body of the plant support rod made of the wood material.

[0033] In addition, it is possible, for example, for the at least one outer layer to be formed by coating a base body of the plant support rod made of the wood material with the plasticized polymer material of the at least one outer layer and solidifying the same, which can be done, for example, by hot pressing or spraying the plasticized polymer material onto the base body made of the wood material.

[0034] Furthermore, it can be provided, for example, that the at least one outer layer is formed by film-coating a base body of the plant support rod made of the wood material with at least one film made of the polymer material of the at least one outer layer, by laminating the film made of the polymer material, for example, onto the base body.

[0035] As already mentioned, the invention makes it possible, while ensuring a nevertheless long service life of the plant support rod, in particular to select the wood material of the base body of the plant support rod from the group of rapidly growing softwoods that can be cultivated in domestic forests, such as in particular from the group of spruce, pine, fir, larch, Douglas fir, birch, alder, poplar, willow and the like.

[0036] The invention also relates to a browsing protection kit comprising at least one plant support rod of the aforementioned type and at least one growth sleeve attachable thereto, so that the plant support rod according to the invention can also serve to secure the growth sleeve. The growth sleeve can, in principle, be of any known shape and, for example, be designed as known from DE 20 2022 105 190 U1, which was not yet published at the priority date of the present application.

[0037] For the reasons stated above, the growth sheath of such a browsing protection kit can preferably itself be formed from a polymer material which has a proportion of between approximately 10% by mass and approximately 100% by mass of at least one biodegradable polymer, wherein this can in particular be a polymer material of the type described above with regard to the at least one outer layer of the plant support rod, so that the growth sheath is also unable to release any long-term stable (micro)plastic particles.

[0038] In addition, the browsing protection kit can further comprise at least one fastening means suitable for fastening the growth cover to the plant support rod, in particular in the form of cable ties.

[0039] The fastening means can preferably also be formed from a polymer material which has a proportion of between approximately 10% by mass and approximately 100% by mass of at least one biodegradable polymer, wherein this can advantageously again be in particular a polymer material of the type described above with regard to the at least one outer layer of the plant support rod.

[0040] Further features and advantages of the invention will become apparent from the following description of exemplary embodiments with reference to the drawings. In the drawings:

[0041] Fig. 1 is a schematic side view of an embodiment of a plant support rod according to the invention;

[0042] Fig. 2 is a schematic side view of another embodiment of a plant support rod according to the invention;

[0043] Fig. 3 is a schematic cross-sectional view of the plant support rod according to Fig. 1;

[0044] Fig. 4 is a schematic cross-sectional view of the plant support rod according to Fig. 2; and

[0045] Fig. 5 is a schematic perspective partial view of a plant support rod according to Fig. 1 or 2, to which a growth sleeve, shown broken off downwards, has been attached.

[0046] 1 and 2 schematically show embodiments of plant support rods 1 according to the invention, which differ primarily in the shape of their cross-section, the plant support rod 1 according to FIG. 1 having a round, e.g. substantially circular, cross-section, while the plant support rod 1 according to FIG. 2 has a polygonal, e.g. rectangular or substantially square, cross-section. At its lower end in FIGS. 1 and 2, which is intended for ramming into the ground, the plant support rod 1 can, for example, taper or become pointed in order to facilitate ramming into the ground.

[0047] As can be seen from Figs. 3 and 4, the plant support rod 1 has a base body 2 made of a wood material, in particular from the group of softwoods, such as spruce, pine, fir, larch, Douglas fir, birch, alder, poplar, willow and the like, to which an outer layer 3 made of a polymer material is applied at least partially, e.g. at its lower end section, or essentially entirely, in order to protect the wood material of the base body 2 from premature biological degradation. The polymer material of the outer layer 3 is a polymer material based on biodegradable polymers, as described in detail above, wherein the polymer material can be mixed with fillers and / or additives of the type also explained above. The thickness of the outer layer 3 can expediently be in the range between approximately 0.5 mm and approximately 1 mm. As the Fig .5 can be seen, the plant-.

[0048] Support rod 1 can also be used to attach a growth sleeve 4 using suitable fastening means, such as cable ties 5, wherein both the growth sleeve 4 and the fastening means can preferably be made from a polymer material based on biodegradable polymers, as explained in detail above. The plant support rod 1, the growth sleeve 4 and optionally the fastening means can in particular be parts of a browsing protection kit which can be used in forestry, horticulture or landscaping, on the one hand to provide support in particular to young plants, including trees, and on the other hand to protect them from being browsed by (wild) animals over a certain period of time.

Claims

Plant support rod (1) for supporting plants, in particular trees, which is made primarily of a wooden material and is designed to be driven into the ground, characterized in that the Plant support rod (1) is at least partially provided with at least one outer layer (3) made of a polymer material which has a proportion between 10 mass% and 100 mass% of at least one biodegradable polymer. Plant support rod according to claim 1, characterized in that - at least one end section of the plant support rod (1) intended to be driven into the ground and / or - at least the outer surface of the plant support rod (1) and / or - substantially the entire surface of the plant support rod (1) is provided with the at least one outer layer (3) made of the polymer material. Plant support rod according to claim 1 or 2, characterized in that the thickness of the at least one outer layer (3) made of the polymer material - at least 0.1 mm, in particular at least 0.2 mm, and / or - not more than 3 mm, in particular not more than 2 mm. Plant support rod according to one of claims 1 to 3, characterized in that the polymer material of the at least one outer layer (3) has a proportion of the at least one biodegradable polymer of at least 20 mass%, in particular of at least 30 mass%, preferably at least 40 mass%. Plant support rod according to one of claims 1 to 4, characterized in that at least one biodegradable polymer of the polymer material of the at least one outer layer (3) is selected from the group of at least partially bio-based polymers. Plant support rod according to one of claims 1 to 5, characterized in that the polymer material of the at least one outer layer (3) - a water solubility of not more than 0.5 g / l, in particular not more than 0.1 g / l, and / or - at least one filler embedded therein, in particular from the group of natural fillers, such as cellulose, wood, lignin, reed, miscanthus, hemp, seaweed, nutshells, crushed fruit kernels and the like. Plant support rod according to one of claims 1 to 6, characterized in that at least one biodegradable polymer of the polymer material of the at least one outer layer (3) is selected from the group of thermoplastic polymers, in particular from the group - polyhydroxyalkanoates, in particular polyhydroxy- butyrate (PHB), Poly-4-hydroxybutyrate (P4HB), Polyhydroxyvalerate (PHV), Polyhydroxyacetic acid, Poly (3-hydroxybutyrate-co-4-hydroxybutyrate), Poly (3-hydroxy-butyrate-co-4-hydroxybutyrate), Poly (3-hydroxybutyrate-co-4-hydroxybutyrate), Polyhydroxyhexanoate (PHH) and / or polyhydroxyoctanoate (PHO); - Polylactide (PLA); - starch and / or its derivatives; - polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS) and / or polybutylene succinate adipate (PBSA); - polysaccharides and / or their derivatives; - lignin and / or its derivatives; - Polycaprolactones (PCL); - proteins and / or their derivatives, including blends thereof. Plant support rod according to one of claims 1 to 7, characterized in that at least one biodegradable polymer of the polymer material of the at least one outer layer (3) is selected from the group of elastomeric polymers, in particular from the group of natural rubber. Plant support rod according to claim 7 or 8, characterized in that the polymer material of the at least one outer layer (3) has a melting point of at least 70°C, in particular of at least 80°C, preferably of at least 90°C. Plant support rod according to one of claims 7 to 9, characterized in that the at least one outer layer (3) - by at least partially immersing a base body (2) of the plant support rod (1) made of the heating material into the plasticized thermoplastic polymer material of the at least one outer layer (3) and solidifying the polymer material, or - by extruding the thermoplastic polymer material of the at least one outer layer (3) onto a base body (2) of the plant support rod (1) made of the wood material, or - by coating a base body (2) of the plant support rod (1) made of the wood material with the plasticized polymer material of the at least one outer layer (3) and solidifying the same. Plant support rod according to one of claims 1 to 9, characterized in that the at least one outer layer (3) is formed by film-coating a base body (2) of the plant support rod (1) made of the wood material with at least one film made of the polymer material of the at least one outer layer (3). Plant support rod according to one of claims 1 to 11, characterized in that its wood material is selected from the group of softwoods, in particular from the group of spruce, pine, fir, larch, Douglas fir, birch, alder, poplar, and willow. Browsing protection kit, comprising at least one Plant support rod (1) according to one of claims 1 to 12 and at least one growth sleeve attachable thereto 14. A browsing protection kit according to claim 13, characterized in that the growth sleeve (4) is in turn formed from a polymer material which has a proportion of between 10 mass% and 100 mass% of at least one biodegradable polymer, in particular from a polymer material according to one of claims 4 to 9.

15. A browsing protection kit according to claim 14 or 15, characterized in that it further comprises at least one fastening means suitable for fastening the growth sleeve (4) to the plant support rod (1), wherein the fastening means is in particular formed from a polymer material which has a proportion of between 10 mass% and 100 mass% of at least one biodegradable polymer, in particular of a polymer material according to one of claims 4 to 9.

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