JP6469142B2 - Woody soil and its manufacturing method - Google Patents

Description

  The present invention relates to a woody soil suitable for agriculture and horticulture and a method for producing the same.

  Lightly cultivated soil made from plant fibers, such as ground coconut shell and peat moss, is often used for agriculture and horticulture. Such a cultivation soil made from plant fibers is not only lightweight, but also has the advantage of being able to increase the porosity during cultivation due to its fiber content and being excellent in water retention and water permeability. In addition, "culture soil" as used in this book is a conceptual thing, and means the material which comprises the foundation for cultivating a plant.

  However, for example, when pulverized coconut shell is used, it contains a large amount of tannin (mixture that produces polyhydric phenolic acid such as gallic acid by hydrolysis) and salt, which inhibits plant growth. There's a problem. Therefore, it is carried out for a long period of time and exposed to rain water or immersed in a water tank to remove tannin and salt, but it takes time and effort, and unless appropriate management is performed, Not only does the quality vary, but, for example, when used in hydroponics, these tannin components are mixed with the drained effluent discharged from it, which may cause river pollution. Then, when utilizing these plant fibers as culture soil, the method of reacting a tannin with an iron ion and inactivating is proposed (patent documents 1, 2).

  For example, in Patent Document 1, the coconut shell is immersed in an aqueous solution of ferrous sulfate for two weeks, and then the pH is adjusted with calcium hydroxide, dried and pulverized to form a soil. Moreover, in patent document 2, after immersing the coconut pulp overnight in the water tank which put the iron plate etc., pressing and water immersion are repeated, it dries and cuts, and the mat for solution cultivation is formed.

  Wood is generally mixed with food residues, livestock excrement, etc., and composted (naturally fermented) is used as compost, but composting requires a long storage time and a vast storage space. There is. Therefore, a soil (woody soil) made of uncomposted wood has been proposed (Patent Documents 3 and 4).

  That is, Patent Document 3 discloses a method of pulverizing trunk branches and leaves of a pruned tree with a compression pulverizer and reducing it to soil. Patent Document 4 discloses a soil-modifying material made of a wooden defibrated material obtained by steaming and pulverizing wood. Although tannin is also contained in wood, Patent Documents 3 and 4 do not consider tannin.

Japanese Patent Laid-Open No. 11-89422 JP 2004-166524 A Japanese Patent Laid-Open No. 10-130084 JP 2006-6254 A

  By applying the techniques of Patent Documents 1 and 2 to the techniques of Patent Documents 3 and 4, there is a possibility of removing tannin contained in the wood. However, even in that case, there is still room for improvement because it still takes time and effort. Further, as a result of investigations by the present inventors, it was found that iron sulfate is effective for inactivating tannin, but can itself inhibit plant growth.

  Therefore, an object of the present invention is to provide a woody soil that can be mass-produced in a short time and can grow plants well.

  One aspect of the present invention is a woody soil composed of uncomposted wood fragments formed by crushing softwood wood, wherein the wood fragments contain ammonium iron citrate.

  Since pulverized wood is difficult to biodegrade and hard to ripen, its quality can be maintained over a longer period of time than the above-described coconut shell and the like after starting use as soil. Among woods, especially softwoods are harder to ripen than hardwoods, are superior in quality stability, and a lot of scraps are generated during the production of plywood and laminates as building materials. Thus, the raw material can be obtained stably. Since it is not composted, it can be manufactured in a short time without requiring a long storage time and a vast storage space.

  Since it is composed of crushed wood fragments, it is possible to adjust the water retention and water permeability according to the plant to be grown by changing the degree of dissolution of the fiber component of the wood.

  Because the wood fragments contain ammonium iron citrate (that is, remain), a sufficient amount of ammonium iron citrate is added, and the tannin contained in the wood fragments is sufficiently inactivated. Has been. Therefore, plant growth inhibition can be prevented stably and effectively. Since ammonium iron citrate does not cause growth inhibition like iron sulfate, plants can grow well.

  It is preferable that the wood fragments further contain a surfactant.

  Wood, especially coniferous trees, once dried, develops water repellency and becomes difficult to absorb water. Even if the soil is dried due to midsummer solar radiation, forgetting to water, etc., by containing a surfactant, an effect of suppressing plant growth inhibition due to the expression of water repellency can be obtained.

  The wood fragments are preferably sized to pass a mesh in the range of 3 mm to 20 mm. The definition of the mesh size used in the present invention refers to the equivalent of the nominal opening of the test sieve defined in JIS Z8801-1.

  The water retention and permeability of woody soil are affected by the particle size distribution. The required water retention and water permeability varies depending on the plant to be cultivated, but an arbitrary particle size distribution can be obtained depending on the size of the mesh. Therefore, the water retention and water permeability appropriate for the target plant can be adjusted by changing the mesh size. can do. A large piece of wood that does not pass through the 20 mm mesh tends to block the growth of the root and inhibit its growth, and if such a large piece of wood is included, the particle size distribution varies and is difficult to handle. By adjusting the size to pass through a mesh of 20 mm or less, an appropriate particle size distribution can be obtained, and appropriate water retention and water permeability can be adjusted. On the other hand, a pulverized product smaller than 3 mm is less likely to pass through the mesh when the size of the pulverized product is made uniform through the mesh, and the production efficiency is significantly reduced. Efficiency is good. Most preferably, the wood fragments are produced using a mesh in the range of 3 mm to 20 mm. If it does so, it will be easy to handle, and it will have high water retention and a good quality woody soil.

  Of the wood, the ratio of the sapwood and the core is preferably set in the range of 1: 0 to 1: 1. In particular, the lower the percentage of core material, the better.

  The heartwood contains more tannins that cause growth inhibition than sapwood, and as described above, the amount of tannin contained in the wood fragments can be reduced, which is advantageous for preventing plant growth inhibition by tannins. Become.

  Another one of the present invention is a method for producing a woody soil.

  The manufacturing method includes a first step of crushing coniferous wood to form a piece of wood, and a second step of treating the piece of wood with a solution, wherein the second step comprises an absolute dry weight of the piece of wood. 1st modification process which makes 0.5 weight% or less iron ammonium citrate act on the said wood crushed piece with respect to the above is characterized.

  According to this manufacturing method, the woody soil as described above can be industrially manufactured, so that it can be mass-produced in a short time. Since iron iron citrate hardly causes growth inhibition even when it is caused to act excessively on wood fragments, tannin can be effectively inactivated. If the amount of iron ammonium citrate is 0.5% by weight or less based on the absolute dry weight of the wood fragments, the plant can be grown stably and satisfactorily.

  In particular, the second step may include a second reforming treatment in which 0.2% by weight or less of iron sulfate is applied to the wood fragments with respect to the absolutely dry weight of the wood fragments.

  Since iron sulfate has high reactivity with tannin, it is effective for inactivating tannin. However, if the appropriate amount is exceeded, the growth of the plant is inhibited due to the concentration disturbance. Therefore, tannin can be inactivated even more efficiently by acting on wood fragments at such a concentration that does not cause concentration disturbance and supplementing the deficiency with ammonium iron citrate.

  The second step may include a third modification treatment in which a surfactant is allowed to act on the wood fragments.

  By causing a surfactant to act on the wood fragments, it is possible to obtain a woody soil that can suppress plant growth inhibition due to the development of water repellency due to drying and that can also promote the growth of plants.

  In particular, each of the first and second reforming treatments is preferably performed by spraying a solution containing the ammonium iron citrate and the iron sulfate onto the wood fragments.

  Then, the reforming process becomes simpler, and it becomes possible to mass-produce high quality wood cultivation soil easily and in a short time.

  The first step includes a fragmentation process for forming the wood fragments by at least one of a process of cutting the wood, a process of crushing the wood by impact, and a process of grinding the wood. preferable.

  By these treatments, a woody soil according to the plant to be grown can be obtained.

  In that case, it is good to make it the said 1st process include the classification process which classify | selects the said wood fragment which passes the mesh of the range of 3 mm-20 mm.

  If it does so, the woody soil excellent in the quality which is easy to handle can be obtained.

  According to the method for producing a woody soil of the present invention, a woody soil that can grow plants satisfactorily can be mass-produced in a short time, and can be provided at a low cost.

It is the schematic which shows an example of the main processes in the manufacturing method of a woody soil. It is the schematic which shows an example of the main processes in the manufacturing method of a woody soil. It is a figure which shows the result of the comparative test 1. It is a figure which shows the result of the comparative test 2. It is a figure which shows the result of the comparative test 3. It is a figure which shows the result of the comparative test 4. It is a figure which shows the result of the comparative test 5.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the following description is merely illustrative in nature and does not limit the present invention, its application, or its use.

<Woody soil>
Currently, cultivation soil composed mainly of peat moss, red jade soil, compost, etc. is used for agriculture and horticulture. The soil is required not only for nutrients but also for water retention, water permeability, pH and other qualities suitable for the plant to be planted. So-called organic materials such as peat moss are used for the purpose of improving or improving soil water retention and air permeability. In recent years, horticulture as a hobby has become established, and for light users who enjoy this, lightness is becoming important. Compost is effective as a soil improvement material (fertilizer), but its production requires a long storage time and a vast storage space.

  Under such circumstances, the present inventors have conducted intensive studies in order to develop a soil that can satisfy these demands by utilizing wood scraps. As a result, we have found a modification method that can effectively inactivate tannin, which causes plant growth inhibition, and developed a new soil (woody soil) to replace them. The details will be described below.

(Raw material for woody soil)
Woody soil is composed of fine wood chips that are not composted, and the main raw material is coniferous wood.

  Here, not composting means that the polysaccharides and the like constituting the wood are not biodegraded due to ripening. Although the woody soil is subdivided, the fiber component of the wood mainly composed of cellulose remains as it is. Since the fiber component of wood is difficult to biodegrade, as described later, the cultivation conditions suitable for the plant to be grown can be obtained by crushing the wood and forming it into pieces of wood in a predetermined form with different water retention and water permeability. Can be maintained for a long time.

  Domestic conifers such as cedar and cypress are suitable as raw materials for the woody soil. Since hardwoods are more likely to rot than softwoods, they are less stable in quality than softwoods. Coniferous trees are less likely to rot, so appropriate and stable pF values (indicators of the amount of water in the soil that plants can absorb to grow) and three-phase distribution (solid phase, liquid phase, gas phase) Can be maintained over time.

  Furthermore, domestic conifers are often used as building materials and wood processing materials, and a large amount of offcuts (excess pieces of wood) are generated during the production. Since the offcuts can be used as raw materials for woody soil, inexpensive raw materials can be secured stably.

  Tannin is abundant in the bark especially in the wood part, but is also present in the sapwood (the peripheral part of the tree) and the heartwood (the central part of the tree). And heartwood tends to have more tannin content than sapwood. Therefore, it is preferable to use more sapwood as a raw material than a core material. Specifically, it is preferable to set the ratio of wood as a raw material so that the ratio of sapwood and core material is in the range of 1: 0 to 1: 1.

  The edge material of sap is generated in a large amount as a back plate or a processed edge material when making a pillar material or the like. The percentage of sap can be increased by preferentially using such sap ends. Further, when manufacturing a plywood or a laminated material, there is a step of peeling a log divided into a predetermined dimension in the length direction from the outer periphery to the center with a predetermined thickness in order to form a thin plate. The ratio of sapwood can be increased by using the first peeling start of the process. On the other hand, it is possible to reduce the ratio of the core material by removing the end material consisting of the central portion of the log, which is called the peeled core, remaining from the raw material of the woody soil. In addition, since younger trees have a higher sapwood ratio in the trunk, the use of thinned wood can reduce the percentage of heartwood compared to the case of using large diameter trees. In this way, the ratio between the core material and the sapwood can be adjusted.

  For woody soil, as an auxiliary material, a modifier made of ammonium iron citrate or iron sulfate for the purpose of inactivating tannin contained in wood, a surfactant or pH adjustment for the purpose of quality improvement An agent has been added.

  Iron sulfate, specifically ferrous sulfate, is highly reactive with tannin, so it is effective for inactivating tannin. However, excessive addition may cause plant growth inhibition. It became clear (details are described later). Specifically, it has been found that if the concentration of iron sulfate added to the wood fragments exceeds 0.2% by weight based on the absolute dry weight of the wood fragments, it may cause plant growth inhibition.

  On the other hand, ammonium iron citrate is less reactive with tannin than iron sulfate, but even when added at a high concentration of 0.5% by weight based on the absolute dry weight of wood fragments, it inhibits plant growth. I was not able to admit. From this, it became clear that ammonium iron citrate is effective as a modifier for woody soil.

  Therefore, it is preferable to add to the woody soil an amount of iron citrate that can sufficiently inactivate the tannin contained in the wood fragments as a modifier for inactivating tannin. Furthermore, it is more preferable to add an amount of iron sulfate that does not inhibit plant growth and an amount of ammonium iron citrate that can sufficiently inactivate the deficient tannin. For this reason, iron sulfate and ammonium iron citrate are used in combination in this woody soil.

  Wood shards produce water repellency when dried. When the woody soil is composed of wood fragments having water repellency, the water retention is deteriorated and the water distribution becomes inhomogeneous due to water repellency, which may lead to inhibition of plant growth. On the other hand, it has been found that addition of a surfactant to wood fragments suppresses plant growth inhibition due to drying (details will be described later). Therefore, in this woody soil, a surfactant is added as an auxiliary raw material.

  In addition, plants generally prefer a weakly acidic to neutral pH, but each has a suitable pH. For this reason, in this woody soil, a pH adjuster according to the plant to be grown is added as an auxiliary raw material. For example, calcium carbonate, bituminous lime, and charcoal as alkaline adjusters, and superphosphate lime and peat moss as acid adjusters are added to the woody soil according to specifications.

(Characteristics of woody soil)
The woody soil is composed of fine wood chips in which the fiber component of the wood remains almost intact, and is set in a form according to the plant to be grown. Specifically, the unraveling condition of the fiber component of wood is set according to the specification. The water content and water absorption are likely to increase as the fiber content is dissolved, and the water permeability (drainage) tends to increase as the wood structure remains.

  As a method of crushing wood as a raw material, for example, a method of cutting wood finely by a cutting crusher such as a rotary saw or a cutter mill (cutting crushing), a method of crushing wood by impact using an impact crusher such as a hammer mill or a pin mill (Impact pulverization), and a method (grinding pulverization) in which wood is crushed by a grinder such as an extruder or ball mill. Among these, since grinding and pulverization are the easiest to unravel the fibers, it is possible to increase water retention and water absorption by crushing wood by grinding and grinding.

  The wood fragments are preferably adjusted to a size that passes through a mesh in the range of 3 mm to 20 mm. A large piece of wood that does not pass through the 10 mm mesh tends to block the root extension and inhibit its growth, and if such a large piece of wood is included, the particle size distribution varies and is difficult to handle. By adjusting the size to pass through a 10 mm mesh, an appropriate particle size distribution can be obtained, and appropriate water retention and water permeability can be adjusted. On the other hand, a mesh smaller than 3 mm is not preferable because the production efficiency is remarkably lowered. Preferably, production efficiency is good by making a material that passes a mesh of 3 mm or more.

  Iron sulfate has a high reactivity with tannin and is added in an amount that is insufficient with respect to the tannin contained in the wood fragments. On the other hand, since an excess amount of iron ammonium citrate is added to the tannin contained in the wood fragments, the iron iron citrate remains in the wood fragments. As a result, the wood debris contains ammonium iron citrate (ie, ammonium iron citrate can be detected from the wood debris).

  Similarly, since a surfactant and a pH adjuster are also added, the wood fragments contain these as well.

  The woody soil can be provided in a state composed only of such wood fragments, for example, by packing the wood fragments into a bag. The woody soil can also be provided in a state in which an appropriate amount of other components useful for plant growth, such as fertilizer, charcoal, lightweight aggregates such as bentonite and zeolite, etc., are mixed with the wood fragments.

<Manufacturing method of woody soil>
The woody soil is produced through a step of crushing coniferous wood (chips) to form wood fragments (first step) and a step of treating the obtained wood fragments with a solution (second step). Since it can be industrially manufactured from uncomposted wood, it can be mass-produced in a short time.

  In the first step, a process of finely pulverizing the mill ends with various pulverizers to form wood fragments (subdivision process) and a process of classifying the wood fragments passing through a mesh of 20 mm or less (classification process) are performed. Is called. In the subdivision process, the various pulverizers described above are selected and used in accordance with the form of the woody soil to be produced. Since it only crushes offcuts, it can be processed in a short time.

  In the classification treatment, only the wood fragments classified to a predetermined particle size are collected by passing the wood fragments obtained by the subdividing treatment through any mesh of 3 mm to 20 mm. From the viewpoint of work efficiency, it is preferable to perform coarse classification by passing a mesh larger than 20 mm in the previous stage. The wood fragments that do not pass through the 20 mm mesh can be processed (recycled) again to improve the processing efficiency. It is most effective to perform the subdivision process and the classification process at the same time while recycling. In addition, when a mesh size less than 3 mm is used, the classification efficiency is significantly lowered. Therefore, it is preferable to use a mesh having a size of 3 mm to 20 mm.

  In a 2nd process, the modification | reformation process aiming at the inactivation of the tannin contained in a timber fragment and the improvement of quality is performed. Specifically, a treatment is performed in which a predetermined amount of each of iron sulfate, ammonium iron citrate, a surfactant, a pH adjuster, and the like is applied to the wood fragments.

  Iron sulfate is effective for inactivation because of its high reactivity with tannin, but when added in excess, it causes plant growth inhibition. Therefore, 0.2 wt% or less of iron sulfate is allowed to act on the wood pieces as an amount that does not inhibit plant growth, based on the absolute dry weight of the wood pieces. Thereby, the total amount of iron sulfate reacts with the tannins of the wood fragments to inactivate the tannins. As a result, unreacted iron sulfate does not remain in the woody soil, or even if it remains, the amount is very small (inhibition of plant growth does not occur).

  On the other hand, the amount of iron sulfate is insufficient with respect to the amount of tannin contained in the wood fragments. Therefore, even if it remains, the amount of iron ammonium citrate that does not cause plant growth inhibition is sufficient to inactivate the remaining tannin within a range of 0.5% by weight or less based on the absolute dry weight of the wood fragments. Make it work. By doing so, tannin can be inactivated effectively and plant growth inhibition can be prevented.

  In general, iron sulfate and ammonium iron citrate are made into an aqueous solution and act on wood fragments. However, when only iron sulfate is used, precipitation is likely to occur due to iron oxidation, so the concentration is stable. There is a problem of not. In contrast, when ammonium iron citrate is added to an aqueous solution of iron sulfate, oxidation is prevented by the reducing action of citric acid, so that precipitation does not easily occur, and there is an advantage that the concentration of iron sulfate is stabilized.

  Moreover, the process which makes each predetermined amount of surfactant and pH adjuster act on a wood piece is performed. Thereby, it can modify | reform to the state more suitable for the plant of growth object, and can promote the growth of a plant.

  In the second step, each component may be allowed to act on the wood fragments by immersing the wood fragments in a water tank in which the reforming liquid is stored, but a treatment for spraying the reforming solution is performed so that mass production can be performed efficiently. Is preferred. An example is shown in FIGS. 1A and 1B.

  Since a predetermined amount of each component only needs to act on the wood fragment, as shown in FIG. 1A, a predetermined amount of the wood fragment 1 is put into the agitator 2 and the content of each component is stirred while the wood fragment 1 is stirred. A reforming treatment can be performed by spraying a predetermined amount of the reformed liquid with the spray 3 (batch type). According to this method, each component can be made to act uniformly on a large amount of wood fragments 1 in a short time.

  Further, as shown in FIG. 1B, the wood fragments 1 supplied in a fixed amount from the feeder 4 are conveyed by the belt conveyor 5, and the modified liquid adjusted in the content of each component is sprayed by the belt conveyor 5. A predetermined amount is sprayed toward the wood fragments 1 to be conveyed. By doing so, the wood fragments 1 can be uniformly modified. More preferably, a homogeneous process can be performed by stirring using a stirrer such as a continuous mixing stirrer after spraying. According to this method, since the reforming process can be performed continuously, more mass production can be realized. The reforming liquid may be sprayed at once. Further, it may be made uniform while stirring after spraying the reforming solution or during spraying.

  Thus, according to the method of spraying the modifying liquid, each component can be made to act on the wood fragments uniformly in a short time. Since the necessary and sufficient amount of the reforming liquid is sufficient, it is extremely efficient. If the reforming solution is heated at the time of spraying (for example, 50 ° C. or more), the removal of moisture can be promoted, so that the treatment can be performed more efficiently.

<Examination of inactivation of tannin>
Next, the contents examined on inactivation of tannin will be described.

(Comparative test 1)
The effects of iron sulfate and ammonium iron citrate on plant growth were investigated. In the test, each aqueous solution of iron sulfate and ammonium iron citrate adjusted to have the same electrical conductivity (EC) (approximately 0.5 μS / cm) was prepared, and each filter paper spread on a separate petri dish An aqueous solution was added. After seeding about 12 komatsuna seeds on each filter paper, the seedlings were raised for about 7 days under dark conditions.

  FIG. 2 shows the result. With iron sulfate, poor germination was observed, but with iron ammonium citrate, poor germination was not observed. From this result, it was found that iron iron citrate is less likely to cause plant growth inhibition by its presence, while iron sulfate causes plant growth inhibition by its own presence.

(Comparative test 2)
The effects of iron sulfate and ammonium iron citrate on plant growth in the presence of tannin were investigated. In the test, aqueous solutions of iron sulfate and ammonium iron citrate were prepared at concentrations of 125 ppm and 500 ppm, 400 ppm of tannic acid was added to these, and the same test as in Comparative Test 1 was performed. Growth status was compared.

  FIG. 3 shows the result. In the figure, (a) is a blank test result (only tannic acid 400 ppm). (B1) is a test result at tannic acid 400 ppm + iron sulfate 125 ppm, and (b2) is a test result at tannic acid 400 ppm + iron sulfate 500 ppm. (C1) is a test result at 400 ppm tannic acid + 125 ppm iron citrate, and (c2) is a test result at 400 ppm tannic acid + 500 ppm iron ammonium citrate.

  From FIG. 3 (a), it can be seen that in the presence of only tannic acid, root hairs are hardly observed and growth is inhibited (the same result has been confirmed even at a concentration of about 200 ppm). On the other hand, from (b1) and (c1) in FIG. 3, in the test section where each iron salt was added at a concentration of 125 ppm with respect to 400 ppm of tannic acid, root hairs were observed and growth inhibition by tannic acid was suppressed. I know that. That is, with respect to 400 ppm of tannic acid, inhibition of plant growth by tannin can be prevented by adding about 125 ppm of iron salt.

  On the other hand, from (b2) of FIG. 3, in the test section where iron sulfate was added in an excessive amount of 500 ppm with respect to 400 ppm of tannic acid, root hairs were hardly observed, whereas from (c2) of FIG. Root hairs were observed in the test section in which iron ammonium citrate was added in an excessive amount of 500 ppm with respect to tannic acid. In other words, iron sulfate was found to be impaired in concentration, and excessive addition thereof caused plant growth inhibition, whereas iron ammonium citrate was found not to be impaired in concentration. It was found that the possibility of causing inhibition was low.

(Comparative test 3)
The effect of spraying the reforming solution was investigated. In the test, each modified solution of iron sulfate and ammonium iron citrate was prepared by weight percent (0.1, 0.3, 0.5) with respect to the absolute dry weight of the wood pieces, and these were sprayed on the wood pieces. Then, the change in the amount of polyphenol was compared. The amount of tannin was measured by measuring the amount of polyphenol using the Folin-Ciocalteu method.

  FIG. 4 shows the result. There was no significant difference depending on the type and concentration of the iron salt, and the amount of polyphenol decreased in all test sections compared to the blank (no treatment). Accordingly, it has been found that tannin can be inactivated by spraying a modified solution containing an iron salt onto a piece of wood.

(Comparative test 4)
The effect of combined use of iron sulfate and ammonium iron citrate was investigated. In the test, cedar chips (produced by Tokushima) dried at 70 ° C. for 3 days were pulverized with a cutter mill (screen diameter 2 mm) to produce wood fragments. The wood fragments are sprayed with a modified solution containing 0.5% by weight of ammonium iron citrate and different concentrations of iron sulfate with respect to the absolute dry weight, and a woody soil with different iron sulfate spray content is sprayed. Produced. These woody soils were used to raise seedlings of Komatsuna, and the yields after 35 days after sowing were compared.

  FIG. 5 shows the test results. A high yield was obtained in the test section where 0.2 wt% or less iron sulfate coexisted with the absolute dry weight of the wood fragments, including the test section of only 0.5 wt% ammonium iron citrate. A decrease in yield was observed in the test plot where iron sulfate exceeding 0.2% by weight coexisted with the absolute dry weight of the wood fragments.

  Therefore, a woody soil capable of growing plants well by suppressing growth inhibition by tannins by causing at least 0.5% by weight or less of iron iron citrate to act on the wood fragments relative to the absolute dry weight of the wood fragments. Can be obtained. Moreover, the growth inhibition by tannin is also suppressed by allowing 0.2% by weight or less of iron sulfate to act on wood fragments in combination with a sufficient amount of ammonium iron citrate relative to the absolute dry weight of the wood fragments. A woody soil that can grow plants well can be obtained.

(Comparative test 5)
The effect of adding a surfactant was investigated. In the test, wood fragments were prepared in the same manner as in comparative test 4, and two samples of woody soil (single section) to which the modified solution consisting only of ammonium iron citrate was added to the wood fragments, iron sulfate and iron citrate. Two samples of wood-cultured soil (combined use zone) to which a modified solution combined with ammonium was added were prepared. An appropriate amount of a surfactant (Saimato EZ: manufactured by Tomo Green Chemical Co., Ltd.) was added to the modified solution of one sample of each woody soil. Using each of the prepared samples, a seedling test of Komatsuna was performed under the same conditions.

  FIG. 6 shows the test results. In both the single and combined samples, the yield increased when the surfactant was added, and the addition of the surfactant was found to be effective for plant growth.

1 Wood fragment 2 Stirrer 3 Spray 4 Feeder 5 Belt conveyor

Claims (10)

Woody soil,
Consists of uncomposted wood fragments formed by crushing coniferous wood,
Woody soil in which the wood fragments contain ammonium iron citrate. In the wood cultivation soil according to claim 1,
A woody soil in which the wood fragments further contain a surfactant. In the woody soil according to claim 1 or claim 2,
Woody soil that is large enough for the wood fragments to pass through a mesh in the range of 3 mm to 20 mm. In the woody soil according to any one of claims 1 to 3,
A woody soil in which the ratio of sapwood and heartwood is set in a range of 1: 0 to 1: 1 in the wood. A method for producing woody soil,
A first step of crushing coniferous wood to form wood fragments;
A second step of treating the wood fragments with a solution;
Including
The manufacturing method of the woody culture soil in which the said 2nd process includes the 1st modification process which makes 0.5 weight% or less iron ammonium citrate act on the said wood fragment with respect to the absolute dry weight of the said wood fragment. In the manufacturing method of Claim 5,
The manufacturing method of the woody culture soil in which the said 2nd process includes the 2nd modification | reformation process which makes 0.2 weight% or less iron sulfate act on the said wood fragment with respect to the absolute dry weight of the said wood fragment. The manufacturing method according to claim 6,
A method for producing a woody soil, wherein the second step includes a third modification treatment in which a surfactant is allowed to act on the wood fragments. In the manufacturing method of Claim 6 or Claim 7,
The manufacturing method of the woody soil by which each said 1st and 2nd modification process is performed by spraying the solution containing the said iron ammonium citrate and the said iron sulfate on the said wood fragment. In the manufacturing method of Claim 5,
The first step includes a subdividing process for forming the wood fragments by at least one of a process of cutting the wood, a process of crushing the wood by impact, and a process of grinding the wood. A method for producing soil. In the manufacturing method of Claim 9,
The manufacturing method of the woody soil in which the said 1st process includes the classification process which sorts | selects the said wood piece which passes the mesh of the range of 3 mm-20 mm.