FR3070826B1 - METHOD OF DEVITALIZING PLANTS - Google Patents

Abstract

The subject of the invention is a process for the devitalization of plants, advantageously woody, having a reduced and controlled environmental impact or even zero, which does not involve plant protection products and / or their adjuvants prohibited by national and / or international laws and regulations. and advantageously that does not involve large mechanical means to maintain the integrity of the soil and structures. In a first step of said method, said plant is corked and in a second step is applied to said previously etched area an aqueous anti-healing solution, or is subjected to said previously debarked area to freezing.

Description

The invention is placed in the field of management of green spaces and particularly in the field of eradication of undesirable plants. The use of pesticides has been widespread for many years both in agriculture and to control vegetation on non-agricultural surfaces (gardens, parks, linear infrastructure, etc.) where the stakes are not really sanitary but mostly landscaped and safe.

The main objective then becomes the eradication of plants planted punctually, for example along linear infrastructures (roads, canals, railway networks, etc.) and other green spaces.

Thus, herbicides and other devitalising products have been favored more rudimentary methods for their many benefits (low cost, ease of application, speed and efficiency).

Vegetation along watercourses, natural or man-made, may eventually cause problems such as the destruction of banks and premature degradation of the structures. It is regularly necessary to eradicate these plants in order to preserve the integrity of the banks and structures.

With the rise of awareness of the dangerousness of certain plant protection products, national regulations have been strengthened.

In France for example the publication of the Order of 12 September 2006 (NOR: AGRG0601345A), recently replaced by the Order of 4 May 2017 on the placing on the market and use of plant protection products and their adjuvants Article L253-1 of the Rural Code and Sea Fisheries (NOR: AGRG1632554A) prohibits the use of plant protection products within 5 meters of watercourses.

Faced with plants under development, which can generate risks, few solutions exist today.

The first solution considered by managers is the felling of trees. This method is the most used because it does not require repair work and does not involve too much cost. However, simply cutting a tree does not always stop growth and death. Some species are known to reproduce vegetatively and a cut reinforces their root system. New suckers from the stump and suckers from the roots may appear more or less rapidly. And in the case where the tree does not survive, the decomposition of the root system still present can cause even greater damage and heavy consequences for the safety of hydraulic structures. Other methods using heavy mechanical means such as the grinding of stumps or staining can be considered.

The grinding of the strains results in identical results to slaughter or even more harmful. In fact, the strain that has become invisible after grinding is often forgotten during visual inspections, while the intact lateral roots continue to develop in the work (appearance of suckers) or they decompose.

Stump removal is the most effective solution: the aerial part is first cut before proceeding with the extraction of the entire root system. But again it is very important that all the roots are removed because forgetting part of the root system can lead to the growth of new shoots (suckers) or generate risks of internal erosion after decomposition. In addition, this technique often requires the use of heavy mechanical means that generate additional degradations that can then be added to the problems posed by the presence of plants.

For example, in the case of hydraulic structures whose banks may be made of rigid coatings, this curative method involves carrying out major destruction and repair work in order to maintain the watertightness of the structures. In-fine, the repair areas are subsequently sensitive areas (joints) where the vegetation will develop more easily compared to homogeneous linear.

It is understood from the foregoing that existing solutions to replace the chemical eradication of plants are not very effective and / or generating other consequences that can render the operation ineffective.

It therefore becomes necessary to find new methods of destroying plants and especially woody plants, with a reduced and controlled environmental impact or even no, which do not involve plant protection products and / or their adjuvants prohibited by national laws and regulations and / or international, and advantageously that do not involve large mechanical means to maintain the integrity of the soil and structures. It is one of the objectives of the present invention to provide such a process for the devitalization of plants, particularly ligneous plants.

Thus, the subject of the invention is primarily a process for the devitalization of a plant, advantageously woody, characterized in that: in a first step, the bark of said plant may be removed from a previously pruned area, over all or part of the perimeter of the plant; trunk of said plant, preferably on the entire periphery of the trunk; - In a second step o said debarked area can be brought into contact with an aqueous anti-healing solution, the area thus treated can be covered hermetically and said aqueous anti-healing solution can be left in contact with said plant a sufficient time to prevent healing of said treated area and contribute to the devitalization process; or the temperature of said debarked zone may be lowered to a temperature between -10 ° C. and -50 ° C., preferably between -20 ° C. and -40 ° C., most preferably between -25 ° C. and -35 ° C.

According to a particular embodiment of the method according to the invention, it may further comprise at least a third step in which: a. if in the second step the application of an aqueous anti-healing solution on said debarked zone has been chosen, then the temperature of said debarked and treated zone can be lowered to a temperature between -10 ° C and -50 ° C, preferably between -20 ° C and -40 ° C, very preferably between -25 ° C and -35 ° C; b. if in the second step the temperature of said debarked zone has been lowered to a temperature between -10 ° C and -50 ° C, preferably between -20 ° C and -40 ° C very preferably between -25 ° C and -35 ° C ° C, then said cooled deboned area can be brought into contact with an aqueous anti-healing solution, said treated area can be hermetically covered and said aqueous anti-healing solution can be left in contact with said plant a sufficient time to prevent the healing of said area.

When the third step is performed according to option a) described above, its purpose is not only to cool the previously treated zone to the second step by applying an aqueous anti-healing solution to said debarked zone but also to eradicating by the cold any rejections that could have appeared below the part of the previously treated plant, that is to say between the lower part of the debarked area and the soil. The lowering of the temperature can then be practiced on the previously treated zone but also, advantageously directly, on any rejections that could have appeared.

According to the invention pruning can be achieved by cutting closer to the trunk branches located in the trunk area chosen for debarking to achieve. Any known means can be used to perform pruning, a person skilled in the art will have no difficulty in determining the most effective means adapted to the situation he is facing, such as for example the use of pruning shears or of a wood saw.

Said area of the trunk to be treated may be pruned on all or only part of the perimeter of the trunk of the plant to be treated. Preferably the area to prune can cover the entire perimeter of the trunk of the plant to be treated.

This area of the trunk (pruned area) can extend from the junction between the plant and the soil to a height that can be between 10 cm and 1 m from the ground, preferably between 20 and 50 cm, very preferably between 25 and 35 cm.

Once pruned said trunk area of the plant to be treated can be debarked.

According to the invention the debarking of said trunk area to be treated can be carried out on all or only part of the perimeter of the trunk of the plant to be treated, preferably all, and / or all or only part of it from the height of the pruned area.

Preferably debarking can be performed on the entire perimeter of the trunk of the plant to be treated and over the entire height of the pruned area.

According to the invention the debarking can be carried out on the pruned area of the junction between the plant and the soil to a height which can be between 10 cm and 1 m from the ground, preferably between 20 and 50 cm, very preferably between 25 and 35 cm.

According to the invention debarking can be achieved by removing the different layers constituting the plant to be treated from outside to the inside of the trunk until reaching the xylem. Advantageously according to the invention the debarking can be carried out up to including the cambium.

Preferably according to the invention the debarking can be carried out until complete elimination of the cambium, even more preferably carried out until complete elimination of the cambium without physical damage to the xylem.

Any known means can be used to achieve debarking, a person skilled in the art will have no difficulty in determining the most effective means adapted to the situation that it faces.

For example, in order to achieve debarking it may be possible to make a cut in the plant to bark using a cutting tool (flat, debarking, knife, etc.) then the woody tissue can be lifted to remove from the bark to the cambium, advantageously without damaging the xylem.

Very preferentially according to the invention the debarking can be carried out until complete elimination of all the tissues considered without damage to the xylem. Those skilled in the art will readily determine the tissue corresponding to the xylem either visually or by touching the area to be smooth and moist immediately after the operation.

Preferably, the first step of the process according to the invention can be carried out by debarking a surface of the trunk of the plant to be pretreated beforehand, which can extend from the soil to a height of between 25 and 35 cm, on the the entire perimeter of the trunk of said plant to be treated by removing successive layers of plant tissue from the periphery inwards until reaching the xylem without damaging or eliminating it.

According to the invention a first variant of the second step of the process may consist in bringing into contact an aqueous anti-healing solution with said debarked area of said plant to be treated.

By bringing into contact is meant according to the invention that an aqueous anticatrixing solution can be deposited by any known means on the surface of the zone exposed by the debarking carried out in the first step, in order to cover all or part of said bark area.

It is therefore understood that according to the invention said aqueous anti-healing solution can be brought into contact with the xylem.

According to the invention, said aqueous anti-healing solution may be a solution chosen from: an aqueous solution (A) comprising between 2% and 15%, preferably between 4% and 12%, very advantageously between 6% and 10% by weight; acid (also referred to herein as "acidic aqueous solution (A)"); An aqueous solution comprising inorganic salts (B), advantageously an aqueous saline solution saturated with mineral salts; - Solution composed of the mixture of the two previous solutions (A + B).

According to a first variant of the invention, said anti-healing solution may be an aqueous acidic solution (A) which may comprise water and at least one acid which may be taken alone or as a mixture, chosen from lactic acid ( C3H6O3), citric acid (C6H8O7), abscisic acid (C15H20O4), methanoic acid (CH2O2), acetic acid (CH3COOH), salicylic acid (C7H6O3), nonanoic acid (C9H18O2) , butyric acid (C4H8O2), benzoic acid (C7H6O2), hypochlorous acid (HOCI), boric acid (H3BO3), sulfurous acid (H2SO3), advantageously lactic acid, citric acid or acetic acid or lactic acid, very advantageously acetic acid or lactic acid, still more advantageously acetic acid, in a proportion which may be between 0.1% and 20%, preferably between 1% and 15%, very advantageously between 2% and 10% of acid. Unless otherwise indicated in this text the percentages are given volume / volume.

According to a preferred form, said acidic aqueous solution (A) may be milk or vinegar, alcohol or fruit, advantageously alcohol. In this case, the acetic acid may be in said acidic aqueous solution (A) consisting of vinegar, in a proportion which may be between 2% and 15%, preferably between 4% and 12%, very advantageously between 6% and 10%. %.

According to the invention, said acidic aqueous solution (A) may have a pH of between 1 and 6.9, preferably between 2 and 5, very advantageously between 2.8 and 3.

According to a second variant of the invention, said anti-healing solution may be an aqueous saline solution (B) comprising at least one mineral salt, which may be chosen from calcium (Ca), iron (Fe) and magnesium (Mg). , Phosphorus (P), Potassium (K), Sodium (Na), Suffer (S), Aluminum (Al), Arsenic (As), Boron (B), Bromine (Br) , Chlorine (Cl), Chromium (Cr), Cobalt (Co), Copper (Cu), Fluorine (F), Iodine (I), Manganese (Mn), Molybdenum (Mo), Nickel (Ni), Lead (Pb), Silicon (Si), Selenium (Se), Vanadium (V), Zinc (Zn), Plutonium (Pu).

Preferably, according to the invention, said mineral salt may be chosen from calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), chlorine (Cl) or iodine (I). Very preferably, said mineral salt may be sodium (Na), chlorine (Cl) or potassium, even more preferably said mineral salt may be sodium (Na).

Advantageously according to the invention, said mineral salt may be present in said aqueous salt solution in the form of cation / anion pair forming a neutral salt, said mineral salt being able to be chosen from the salts mentioned above, with the same preferences.

According to a form of the invention, said saturated aqueous salt solution with mineral salts may comprise the mixture of at least one mineral salt and its cation / anion form forming a neutral salt.

According to another form of the invention, said aqueous saline solution saturated with inorganic salts can comprise the mixture of several inorganic salts and their cation / anion form forms forming a neutral salt.

According to yet another form of the invention, said saturated aqueous salt solution with mineral salts may comprise the mixture of at least one mineral salt and at least one other mineral salt in its cation / anion form forming a neutral salt.

Very preferably according to the invention, said saturated aqueous saline solution with mineral salts may comprise exclusively at least one mineral salt in cation / anion pair forming a neutral salt.

Of course, according to the invention, said saturated aqueous saline solution with mineral salts may exclusively comprise several inorganic salts in the form of cation / anion pairs forming a neutral salt.

According to the invention, the cation / anion pair forming a neutral salt may be at a concentration of between 1/3 of the amount necessary for saturation and saturation, preferably between 2/3 of the amount necessary for saturation and saturation, very preferentially at saturation.

By saturation is meant in the present text the concentration, expressed in g / L, from which said cation / anion pair forming a neutral salt can not dissolve in water at a given temperature, generally 20 ° C or 25 ° vs.

Preferably according to the invention, said aqueous saline solution can be saturated.

According to the invention, by way of example, said cation / anion pair forming a neutral salt can be chosen from the pairs Sodium Chloride (NaCl), Calcium Chloride (CaCl 2), Potassium Chloride (KCl), Magnesium Chloride (MgCl 2) ), sodium iodide (NaI), potassium iodide (Kl), sodium bicarbonate (NaHCO3), preferably Sodium Chloride (NaCl) or potassium chloride (KCl), very preferably Sodium Chloride (NaCl). By way of example, the following table gives the value (in g -1 L'1) of the saturation concentration in water at the temperature indicated for certain neutral salt-forming cation / anion pairs that can be used according to the invention.

According to a third variant of the invention, said anti-healing solution may be a mixture of the two preceding solutions, namely a mixture of an aqueous acidic solution (A) and an aqueous saline solution (B), in a ratio A / B (vol / vol) between 1/99 and 99/1, preferably between 25/75 and 75/25, even more preferably 50/50. By way of example, said anti-healing solution in the form of a mixture of an aqueous acid solution (A) and an aqueous saline solution (B) may be chosen from

the mixture of an aqueous solution based on acetic acid (A) and an aqueous saline solution (B) comprising the NaCl couple, or alternatively a mixture of an aqueous solution based on citric acid (A) and an aqueous saline solution (B) comprising the MgCl 2 pair, or a mixture of an aqueous solution based on citric acid (A) and a saline solution (B) based on KCl, or alternatively an aqueous solution based on lactic acid and aqueous saline solution (B) based on NaHCO 3.

In a preferred manner according to the invention, said anti-healing solution may be a mixture of an aqueous acidic solution (A) and an aqueous saline solution (B) in a 50/50 ratio, with an aqueous solution based on 6% acetic acid (A), at a pH of between 2.8 and 3, and with an aqueous saline solution (B) comprising the saturation NaCl couple (358.5 g-1 at 20 ° C.).

The contacting of the anti-healing solution performed in the second step can be carried out by any method known to those skilled in the art such as a painting.

Advantageously, the contacting of the anti-healing solution with the xylem of the plant to be devitalized can be done by applying a dressing soaked with said solution to all or part of the surface of the debarked plant in the first stage, advantageously over the entire area. Said dressing may be paper, advantageously over several thicknesses, of the fabric, advantageously over several thicknesses, a spongy material, advantageously over several thicknesses or alternatively absorbent paper, advantageously over several thicknesses. Preferably according to the invention said dressing may be absorbent paper on several thicknesses.

According to the invention, the area treated with the anti-healing solution can be hermetically covered to form a hermetic bandage in order to slow as much as possible the evaporation of the aqueous anti-healing solution applied to the second stage. This hermetic bandage also has the advantage of preventing said aqueous anti-healing solution from spreading in the non-targeted environment.

Said hermetic bandage may be made using any waterproof material sufficiently flexible to be applied around the debarked area of said plant to be treated. Said material may be applied around said debarked area of said plant to be treated by keeping between it and the xylem said anti-healing solution.

According to a preferred variant said sealed material may be applied around said debarked area of said plant to be treated by maintaining between it and the xylème said dressing soaked with said anti-healing solution.

According to the invention, said waterproof material may be plastic film, stretchable film, tarpaulin, tarpaulin, adhesive tape, preferably stretchable film, such as that sold for example without limitation by Exbanor (FR), Plasticband ( ES) or Strapex (Fr).

Once laid said dressing will be fixed to said plant to be treated by any means known to those skilled in the art. For example it can be glued with glue or tape, for example of the Chatterton type, or stapled.

Preferably said dressing will be fixed to said plant with a stretch film. If said waterproof material is a self-adhesive stretch film it can by stretching and application around the trunk of said plant to be treated to stand alone around said trunk or be kept around the trunk of said plant to be treated using for example tape.

According to the invention, the process may be carried out for a time sufficient for the aqueous anti-healing solution to act. It is understood here that the time of implementation of said method may depend on the resistance of said plant to be treated devitalization by said aqueous anti-healing solution used, which resistance may depend on the nature of said plant, its stage of growth (juvenile adult or senescent), health status or size. In fact it is a careful monitoring of the state of devitalization of said plant, particularly its aerial parts, which will assess over time the progress of said devitalization. Those skilled in the art will easily determine if said plant to be treated is sufficiently devitalized or if the implementation of said process must be continued.

It is thus understood that the implementation time of the process according to the invention can be long and that it may therefore be necessary to reapply the aqueous anticycling solution on the xylem.

Thus, according to another variant of the invention, said method may comprise one or more refilling steps in an aqueous anti-healing solution. This (or these) refill (s) can (can) be done during the second step of the method according to the invention by any known means such as for example the injection of said solution through said dressing occultant in one or more points of said dressing. Here again the skilled person will easily determine the most effective way to use to perform the refill in aqueous anti-healing solution. Injection charging through said dressing may be preferred.

Similarly, the skilled person will easily determine the number of refills to be made and the amount of aqueous anti-healing solution to use.

According to another variant of the second step of the process according to the invention the temperature of said debarked zone can be lowered to a temperature between -10 ° C and -50 ° C, preferably between -20 ° C and -40 ° C very preferably between -25 ° C and -35 ° C.

According to the invention, this cooling step can be carried out by any means known to those skilled in the art which makes it possible to maintain the treated zone at the desired temperature for a sufficient time.

According to the invention this cooling step can be carried out at one time or in several times separated by a temperature rise time of between 1 hour and 1 month, preferably 15 days. When said cooling step is carried out in several times separated by a rise in temperature, the number of times during which the plant can be subjected to cooling may be left to the discretion of those skilled in the art and be between 2 and 10 times. But advantageously this number of times can be between 2 and 4 times and very preferably can be 2 times.

It is understood that the duration of this step, whether performed in one or more times, may depend on the plant species considered, the size of said plant and possibly the environmental conditions undergone.

According to the invention this cooling step can be carried out for a total time of between 1 minute and 180 minutes, preferably between 10 minutes and 150 minutes, very preferably between 30 minutes and 120 minutes. It is therefore understood that if said cooling step is performed in several times the duration of each sub-step will be compatible with the fact that the sum of the duration of the cooling substeps is between 1 minutes and 180 minutes, preferably between 10 minutes and 150 minutes, very preferably between 30 minutes and 120 minutes. By way of example, a cooling sub-step may have a duration of between 1 to 60 minutes, preferably between 10 to 45 minutes, very preferably 30 minutes. As an example of means for cooling said zone include the application of dry ice, liquid nitrogen, or using an apparatus known to plumbers under the name gel-tube as for example those of the brand ROTHENBERGER (France) or the brand RHEMS (Germany).

Preferably, according to the invention, the cooling step may be carried out using a gel-tube.

According to a preferred form of the invention the process may comprise a third step which may be o or a step of cooling said debarked zone to a temperature of between -10 ° C. and -50 ° C., preferably between -20 ° C. and -40 ° C, very preferably between -25 ° C and -35 ° C as described above, if in the second step an aqueous anti-healing solution was applied to the debarked area; or a step of contacting with an aqueous anti-healing solution, said treated zone being hermetically covered and said aqueous anti-healing solution being left in contact with said plant for a time sufficient to prevent the healing of said zone such that this is described previously in the present text, if in the second step the temperature of said debarked zone has been lowered to a temperature between -10 ° C and -50 ° C, preferably between -20 ° C and -40 ° C very preferably between -25 ° C and -35 ° C.

According to the invention the first and the second step can be carried out successively in a short time for example between 5 minutes and 2 hours.

Said third step may take place immediately after the first and second steps have been carried out or preferably after a sufficient time for the effect of the realization of the first and second steps to appear on the treated plant. It is therefore understood that the third step can be performed after the second step in a time between 10 minutes and 2 years. It is the person skilled in the art who will decide the time separating the second and third stages depending on the evolution of the plant after the completion of the first two stages of the treatment.

From the above it is understood that the steps of bringing the xylem into contact with an anti-healing or cooling solution of the debarked zone, whether they are carried out in the second or third stage of the process according to the invention, can be repeated as much as many times that the person skilled in the art will deem useful to renew them. Other aspects of the invention may appear on reading the following figures and examples.

Figure 1 shows a schematic section of a trunk of a plant showing the various tissue layers constituting the trunk (after Christmas, 1970) and a diagram of the debarking zone to practice according to the invention.

By observation of Figure 1 we note from left to right the tissues of a woody plant constituting the bark (cork, phellogen, phelloderm, cortex, phloem), a libero-woody base (cambium) and sapwood (xylem) constituting the wood with the heartwood (dead tissue not shown in Figure 1) further in the center. The xylem and the phloem are sap-conducting tissues, the xylem leads the raw sap composed of water and mineral salts only in an ascending (unidirectional) direction, from the roots to the aerial parts of the plant while the phloem leads the elaborate sap composed of sugars (from photosynthesis) to the roots as well as the other organs of the plant (bidirectional direction). The part of the figure referenced "debarking zone" shows the different tissues that must be removed in the first step of the process according to the invention. The debarking of these tissues cuts the circulation of the sugars necessary for the good development of the plant and provides access to the xylem for the second stage of the process according to the invention.

Example 1. Devitalization of a poplar by bringing the xylem into contact with vinegar:

On a poplar 1.5 m high and 5 cm in diameter at its base, cut at the lowest of the trunk with a pruner branches from the ground up to 50 cm above the ground .

In this area pruned over an area extending from the ground up to 30 cm in height and over the entire perimeter of the tree, the tissues constituting the bark and the cambium are meticulously removed using a plane to make appear on the whole of the zone the xylème whose aspect is smooth and wet just after debarking. The debarking is carried out meticulously so as not to leave any tissue other than the xylem. Upon debarking, the debarked area is covered with several saturation saturated paper towels (i.e., until said absorbent paper holds no more liquid) of 6% red wine vinegar. and whose pH is between 2.8 and 3.

The vinegar saturated paper towel is then covered with a multi-layer stretch film so as to protect the soaked paper towel and to prevent the acid solution from spreading in the environment and evaporating. The lower and upper portions of this dressing are then covered with Chatterton tape so as to seal all around the shaft the junction zone between the shaft and said dressing.

A visual monitoring of the health status of the tree is then performed once a month for one year.

The following health conditions are expected: 1- Some leaves show signs of wilting and / or discolouration. 2- All leaves show signs of wilting and / or discoloration. 3- Some leaves are dry and start to fall. 4- Set of dry leaves still present on the tree or fallen. 5- Absence of new leaves, no rejections present at the base of the trunk or rejects from the roots: the plant is devitalized.

However, insofar as the tree is not completely devitalized at the end of the first year and that suckers / suckers are observed, step 2 is repeated (setting up a new dressing with anti-inflammatory solution). healing).

At the end of 12 months the absence of new leaves and the absence of rejects present at the level of the base of the trunk or rejections from the roots are noted. The tree is then devitalized.

EXAMPLE 2 Devitalization of an acacia garlic tree by gel followed by contacting the xylem with an aqueous solution containing saturated sodium chloride (NaCl) (358.5 g per liter of water at 20 ° C. ):

On an acacia tree 3 m high and 15 cm in diameter at its base, the branches are cut from the ground up to 1 m above the ground at the lowest level of the trunk using a hacksaw.

In this pruned area, a zone extending from the ground up to 50 cm in height and over the entire perimeter of the tree is meticulously removed, the tissues constituting the bark and the cambium using a debarker in order to make appear on the whole of the zone the xylème whose aspect is smooth and wet just after debarking. The debarking is carried out meticulously so as not to leave any tissue other than the xylem. Upon debarking, the debarked area is clamped into the tube gel clamp and the temperature of the enclosed area is lowered to -35 ° C for 60 minutes. The temperature is then allowed to rise for a week and the temperature of the zone is then lowered to -35 ° C for 60 minutes.

A visual monitoring of the health status of the tree is then performed once a month for one year.

When the state of health corresponding to state No. 2 (all leaves show signs of wilting and / or discoloration [see example 1]), the debarked area treated by the cold is covered with several layers of paper. saturated saturated absorbent (i.e., until said absorbent paper retains more liquid) of saturated sodium chloride solution (358.5 gL-1). Sodium chloride is then covered with a multi-ply stretch film to protect the soaked absorbent paper, and the upper and lower parts of the dressing are covered with Chatterton tape to seal all the way around. tree the junction zone between the shaft and said dressing.

A visual monitoring of the health status of the tree is then performed once a month for one year. At each verification of the sanitary state of the plant a random quantity of sodium chloride is injected through the hermetic dressing with the aid of a syringe in order to reload said hermetic dressing in saturated sodium chloride.

At the end of a year, no more leaves are present on the tree and no suckers or suckers have appeared. The tree is then devitalized.

Example 3

A procedure identical to that of Example 2 is carried out on a willow 10 cm in diameter and about 2 m high except that the anti-healing solution applied to the xylem is a 50% solution consisting of saturated calcium chloride (CaCl2) (745 g-L'1) and 50% of a 10% aqueous solution of citric acid and a pH of 2.3.

The devitalization of the tree is observed after 6 weeks of treatment.

Claims (13)

1. A method of devitalizing a plant, preferably woody, characterized in that - In a first step the bark of said plant is removed on a pre-pruned area on all or part of the perimeter of the trunk of said plant; - In a second step o said debarked area is brought into contact with an anticicatrising aqueous solution, the area thus treated being hermetically covered and said aqueous anti-healing solution being left in contact with said plant a sufficient time to prevent healing of said treated area and contribute to the process of devitalization; or the temperature of said debarked zone is lowered to a temperature between -10 ° C and -50 ° C, preferably between -20 ° C and -40 ° C, very preferably between -25 ° C and -35 ° C. 2.) A method according to claim 1, characterized in that it further comprises a third step in which o if in the second step the application of an anticicatrising aqueous solution on said debarked area has been chosen then the temperature of said zone debarked and already treated in the second step is lowered to a temperature between -10 ° C and -50 ° C, preferably between -20 ° C and -40 ° C, very preferably between -25 ° C and -35 ° C VS ; o if in the second step the temperature of said debarked zone has been lowered to a temperature between -10 ° C and -50 ° C, preferably between -20 ° C and -40 ° C very preferably between -25 ° C and - 35 ° C then said debarked area already treated in a second step is brought into contact with an anticicatrising aqueous solution, said treated area being hermetically covered and said aqueous anti-healing solution being left in contact with said plant for a sufficient time to prevent healing of said area. 3.) Method according to any one of claims 1 or 2, characterized in that said debarked area extends from the plant / soil junction to a height between 10 cm and 1 m from the ground, preferably between 20 and 50 cm, very preferably between 25 and 35 cm. 4.) Method according to any one of claims 1 to 3, characterized in that debarking removes the surface tissues of said plant up to including at least cambium. 5. Method according to any one of claims 1 to 4, characterized in that the debarking leaves the xylème intact. 6.) Method according to any one of claims 1 to 5, characterized in that said aqueous anti-healing solution is selected from an aqueous solution (A) comprising between 0.1% and 20%, preferably between 1% and 15%, very advantageously between 2% and 10% of acid (aqueous acid solution (A)); - Saline solution saturated with mineral salts (B); - Solution composed of the mixture of the two previous solutions (A + B). 7. A process according to claim 6, characterized in that said acidic aqueous solution comprises at least one acid selected from, taken alone or as a mixture, chosen from lactic acid (C3H6O3), citric acid (C6H8O7), abscisic acid (C15H20O4), methanoic acid (CH2O2), acetic acid (CH3COOH), salicylic acid (C7H6O3), nonanoic acid (C9H18O2), butyric acid (C4H8O2), benzoic acid (C7H6O2), hypochlorous acid (HOCI), boric acid (H3BO3), sulfurous acid (H2SO3), advantageously lactic acid, citric acid or acetic acid or lactic acid, very advantageously acetic acid or lactic acid, still more advantageously acetic acid, in a proportion that may be between 0.1% and 20%, preferably between 1% and 15% very advantageously between 2% and 10% of acid. 8. Process according to any one of claims 6 or 7, characterized in that said acidic aqueous solution is at a pH of between 1 and 6.9, preferably between 2 and 5, very advantageously between 2.8 and 3. 9.) Method according to claim 6, characterized in that the aqueous saline solution saturated with mineral salts comprises at least one mineral salt selected from calcium (Ca), magnesium (Mg), potassium (K), sodium ( Na), Chlorine (Cl), Iodine (I) preferentially Calcium (Ca), Magnesium (Mg), Potassium (K), Sodium (Na), Chlorine (Cl) or Iodine (I), very preferably Sodium (Na), Chlorine (Cl) or Potassium, more preferably Sodium (Na). 10.) A method according to claim 6, characterized in that the aqueous salt solution saturated with inorganic salts comprises at least one mineral salt cation / anion couple forming a neutral salt, preferably selected from the couples Sodium chloride (NaCl), chloride Calcium (CaCl 2), sodium iodide (NaI), potassium chloride (KCl), magnesium chloride (MgCl 2), potassium lodide (Kl), sodium bicarbonate (NaHCo 3), preferably sodium chloride (NaCl) or potassium chloride (KCl), very preferably sodium chloride (NaCl). 11. A process according to claim 6, characterized in that the solution composed of the mixture of an aqueous acidic solution (A) and a saturated aqueous salt solution saturated with mineral salts (B) is in a ratio A / B (vol. / vol) between 1/99 and 99/1, preferably between 25/75 and 75/25, even more preferably 50/50. 12. A method according to claim 1, characterized in that in the second step the contacting of the debarked area with an aqueous anti-healing solution is by imbibition of an absorbent material, preferably selected from paper, tissue, a spongy material, or even absorbent paper, preferably absorbent paper, positioned in contact with the debarked portion of the plant with said aqueous anti-healing solution. 13. A method according to claim 1, characterized in that in the second step the area treated with the anti-healing solution is hermetically covered with plastic film, stretch film, tarpaulin, tarpaulin, adhesive tape, preferably stretch film.