Ecological prevention and control method for betula alnoides man-made forest trunk borer pseudocotona moth

Abstract

The invention discloses an ecological prevention and control method for trunk borers of betula alnoides in an artificial forest of betula alnoides. According to the method, when a betula alnoides artificial forest is built, melia azedarach and betula alnoides are mixed and planted in a dotted uniform configuration mode. Volatile active substances released by leaves, flowers and fruits of melia azedarach cooperate with toosendanin diffused by carriers such as pollen and tiny tissue debris of melia azedarach to form a biological barrier which can effectively interfere with olfaction localization, growth and development and reproduction behaviors of the parapsilotona in forest air, so that ecological prevention and control of the parapsilotona in the betula alnoides artificial forest are realized. The whole planting density of the betula alnoides artificial forest is 111-167 plants per mu, 101-162 plants of the betula alnoides are planted per mu, 5-10 plants of the melia azedarach are planted per mu, and the maximum ecological prevention and control effect is achieved with the minimum number of the melia azedarach plants. The method can effectively control the damage of trunk borers of Betula alnoides in the artificial forest, reduces the use of pesticides, reduces the prevention and control cost, improves the wood quality, and promotes the sustainable operation of forest stands.

Description

Technical Field

[0001] This invention relates to the field of forestry pest and disease control technology. Specifically, it relates to an ecological control method for the wood-boring moth, a stem-boring pest in plantations of Southwest China birch. Background Technology

[0003] Southwest birch ( Betula alnoides *Buch. Ham. ex D. Don* is a valuable native broad-leaved tree species in southern regions, known for its strong adaptability, rapid growth, and excellent timber. Currently, the area of ​​plantations of *Buch. Ham. ex D. Don* exceeds 200,000 hectares, mostly consisting of young and middle-aged trees. However, in production practice, *Buch. Ham. ex D. Don* is highly susceptible to wood-boring pests, specifically the wood-boring moth (*Buch. Ham. ex D. Don*). Arbela The wood-boring moth (spp.) causes damage. This pest bores into tree trunks, creating tunnels that weaken young trees. Severe infestations can lead to wind damage, top breakage, and even death, directly impacting stand stability and timber quality. Wood-boring moth damage has become a major limiting factor for existing forest stand management and large-scale development.

[0004] Previous studies have found that the bark beetle begins pupating in late March, emerges and mates in early to mid-April, and the larvae begin feeding on the bark and boring into the xylem in May, gradually entering overwintering by mid-December. Controlling the pest during its emergence, mating, and oviposition periods is crucial. Currently, chemical control and black light trapping are commonly used to control the bark beetle in Southwest China. However, due to the vast area of ​​Southwest China birch plantations, traditional chemical control is not only difficult to implement and has limited effectiveness, failing to effectively suppress the bark beetle population, but also increases the cost of plantation management and the risk of environmental pollution due to the large-scale use of pesticides. Black light trapping, on the other hand, may kill beneficial insects along with the bark beetle, seriously negatively impacting the diversity and stability of the forest ecosystem. Therefore, by identifying tree species with special effects as companion species during the emergence, mating, and oviposition periods of the wood-boring moth, and by scientifically configuring new planting models for Southwest China birch, an ecological control method for the wood-boring moth can be developed to achieve green, safe, and efficient control. This is of great significance for the sustainable management and large-scale development of Southwest China birch plantations. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to provide an ecological control method for the wood-boring moth, a borer of Southwest birch plantations, in order to solve the problems of low efficiency, high cost and incomplete control in existing control technologies, thereby effectively maintaining the stability of Southwest birch stands and improving timber quality.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: An ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, involves constructing a mixed planting pattern of Southwest China birch and Chinaberry during the establishment of Southwest China birch plantations. This creates a biological barrier that interferes with the development and reproduction of the wood-boring moth, thereby achieving ecological control of the wood-boring moth in the Southwest China birch plantations.

[0007] The above-mentioned ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, involves intercropping Southwest China birch with Chinaberry in a dotted and uniform manner to form Southwest China birch plantations.

[0008] The above-mentioned ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, involves planting 111-167 trees per mu (approximately 0.067 hectares) in Southwest China birch plantations. The overall planting density of Southwest China birch and Chinaberry in the Southwest China birch plantation is 111-167 trees per mu. The spacing between adjacent trees is 2 m × 2-3 m, that is, the spacing between Southwest China birch and adjacent Chinaberry, as well as between Southwest China birch trees, is 2 m × 2-3 m. Excessive planting density of *Betula spp.* in Southwest China will severely affect its growth, while insufficient planting density will affect the straightness of the trunk and reduce the timber yield per unit area. The planting density of *Betula spp.* in this invention is 101-162 trees per mu (approximately 0.067 hectares); the planting density of *Melia azedarach* is 5-10 trees per mu (approximately 0.067 hectares), with a spacing of 8-10 m × 8-12 m between the *Melia azedarach* trees.

[0009] The above-mentioned ecological control method for the wood-boring moth, a stem borer in Southwest China birch plantations, uses a planting density of 6-8 trees per mu (approximately 0.067 hectares) for Chinaberry.

[0010] The above-mentioned ecological control method for the wood-boring moth, a stem borer in Southwest China birch plantations, uses a plant spacing of 9 m × 10 m for the Chinaberry trees.

[0011] The above-mentioned ecological control method for the wood-boring moth, a stem borer in Southwest China birch plantations, uses a spacing of 2 m × 3 m between adjacent plants.

[0012] Because the timber value of *Melia azedarach* is far lower than that of *Betula spp.*, planting too many would reduce forest management profits. However, by using a dotted, uniform intercropping method with *Betula spp.*, the volatile active substances released by the leaves, flowers, and fruits of *Melia azedarach*, along with azadirachtin dispersed by its pollen and micro-tissue debris, form a biological barrier in the forest air that effectively interferes with the olfactory localization, growth, development, and reproductive behavior of the wood-boring moth. By configuring *Melia azedarach* at the aforementioned density and spacing, the maximum ecological control effect can be achieved with the fewest possible number of plants. This method not only helps save on pest control costs, reduce environmental pollution risks, and improve control efficiency, but also effectively maintains the stability of *Betula spp.* stands and improves timber quality.

[0013] The above-mentioned ecological control method for the wood-boring moth, a stem borer in Southwest China birch plantations, selects neem germplasm with high azadirachtin content (≥0.2%) in its fruit, so that the azadirachtin and volatile active substances in the forest air can reach and maintain an effective critical concentration, thereby ensuring the stability and reliability of the ecological control effect.

[0014] The above-mentioned ecological control method for the wood-boring moth, a stem-boring pest in plantations of *Betula spp.*, is described in which *Betula spp.* and *Melia azedarach* are mixed species of the same age.

[0015] The aforementioned ecological control method for the wood-boring moth, a stem-boring pest in plantations of *Betula spp.* (Southwest China Birch), involves planting *Betula spp.* and *Melia azedarach* (Chinaberry) in a mixed stand of the same age through synchronous planting. Since *Betula spp.* can be damaged by the wood-boring moth even in its sapling stage, and *Melia azedarach* generally requires 4-5 years after planting to flower and bear fruit, synchronous planting of the mixed stand helps coordinate interspecific relationships, promotes the formation of a stable forest stand structure, and establishes a biological barrier against the wood-boring moth as early as possible, fully leveraging the ecological protection function of *Melia azedarach*.

[0016] The above-mentioned ecological control method for the wood-boring moth, a stem borer in Southwest China birch plantations, utilizes the fact that the flowering period of the Chinaberry coincides with the emergence, mating, and oviposition period of the wood-boring moth. The active substances released by the Chinaberry flowers can effectively curb the establishment of the wood-boring moth population by interfering with olfactory localization, repelling adult moths, and inhibiting their development and reproduction. The Chinaberry fruits, whether left on the tree or rotting on the ground, continuously release active substances, affecting the emergence, mating, and oviposition activities of the wood-boring moth.

[0017] The technical solution of the present invention achieves the following beneficial technical effects: 1. This invention achieves ecological control of the wood-boring moth by constructing a mixed planting pattern of *Betula spp.* and *Melia azedarach* during the establishment of *Betula spp.* plantations. This pattern uses *Betula spp.* as the target tree species and *Melia azedarach* as the ecological regulator; *Melia azedarach* is mixed with *Betula spp.* in a dotted, evenly distributed manner. Through this rational layout, the volatile active substances released by the leaves, flowers, and fruits of *Melia azedarach*, along with azadirachtin diffused by its pollen and micro-tissue debris, form a biological barrier in the forest air that effectively interferes with the olfactory localization, growth, development, and reproductive behavior of the wood-boring moth. The flowering period of *Melia azedarach* is concentrated in April and May, coinciding with the emergence, mating, and oviposition period of the wood-boring moth. The active substances released by *Melia azedarach* can effectively inhibit the establishment of its population through multiple pathways, including interfering with olfactory localization, repelling adult moths, and inhibiting development and reproduction, resulting in a particularly significant control effect. The fruits of the chinaberry tree, ripening in November and December, can remain on the tree for an extended period. Their pericarps and pulp are rich in azadirachtin and volatile active substances. From April to May of the following year, whether the fruits remain on the tree or fall to the ground and decompose, they continuously release these active substances, influencing the emergence, mating, and oviposition activities of the wood-boring moth. Therefore, by rationally intercropping neem and birch, a sustained repellent and inhibitory effect can be achieved during key stages of the wood-boring moth's life cycle, significantly reducing the moth population and its damage within the stand, thereby improving stand quality and stability.

[0018] 2. This invention, through the design of planting density and row spacing, achieves effective protection of the entire forest stand by planting only 5-10 chinaberry trees per acre at a low density. Compared with other mixed tree species, this model not only significantly reduces damage from wood-boring moths but also ensures the yield of birch timber from Southwest China, increasing forest land output.

[0019] 3. This invention effectively controls the damage caused by the wood-boring moth to the Southwest birch by intercropping it with Chinaberry, reduces the dependence on chemical pesticides or black light lamps, thereby mitigating the negative impact on the environment and contributing to the protection of biodiversity and sustainable forest management.

[0020] 4. This invention significantly reduces the workload and cost of controlling bark beetles in forest stands by intercropping Southwest Birch and Chinaberry, improves forest stand management efficiency, and thus enhances overall economic benefits. Attached Figure Description

[0021] Figure 1 A schematic diagram showing the effect of mixed planting of Southwest China birch and Chinaberry (no damage from the wood-boring moth was observed); Figure 2 A schematic diagram showing the flowering of Chinaberry in a mixed forest (April); Figure 3 A schematic diagram illustrating the severe damage caused by the bark-boring moth in pure birch forests in Southwest China. Figure 4 A schematic diagram showing the damage (bark) caused by the bark borer of the Southwest birch; Figure 5A schematic diagram showing the damage (boring tunnels) caused by the Southwest Birch Wood Borer. Detailed Implementation

[0022] An ecological control method for the bark borer *Triplophysa gracilis*, a stem-boring pest in plantations of *Betula spp.*, was developed. First, mixed species selection was conducted in areas within the *Betula spp.* cultivation area where *Triplophysa gracilis* frequently occurs. Mixed species experiments were carried out at bases including the Tropical Forestry Experimental Center of the Chinese Academy of Forestry in Pingxiang City, Guangxi Zhuang Autonomous Region; the Weiguo Forestry Bureau in Pu'er City, Yunnan Province; and the Dehong Forestry Research Institute in Yunnan Province. *Betula spp.* was mixed with *Castanopsis fargesii*, *Eucalyptus grandis*, *Pinus yunnanensis*, *Acacia confusa*, *Cunninghamia lanceolata*, and *Melia azedarach* of the same age. Each treatment used a 1:1 strip mixing method, with a pure *Betula spp.* forest as a control. The planting spacing was 2 m × 2–3 m. Six to ten years after planting, 20 m × 30 m plots were set up for each treatment to investigate the growth of *Betula spp.* and the damage caused by *Triplophysa gracilis*. The results are shown in Table 1.

[0023] Table 1. Growth performance and wood-boring moth damage of *Betula spp.* under different mixed planting treatments in various regions. Table 1 shows that, except for *Pinus yunnanensis*, mixing *Betula septemlobus* with other tree species effectively promotes the growth of its diameter at breast height (DBH) and tree height. Furthermore, all mixed planting patterns effectively reduce the damage caused by the borer *Pterocarya stenoptera* to *Betula septemlobus*. In particular, no *Pterocarya stenoptera* damage was observed in the *Betula septemlobus* × *Melia azedarach* pattern, while the infection rate in the control *Betula septemlobus* pure stands ranged from 16.5% to 21.3%, with an average of 1.9 to 2.1 borers per infected tree. Therefore, the *Betula septemlobus* × *Melia azedarach* pattern demonstrates a particularly significant control effect on the borer *Pterocarya stenoptera* and is the optimal mixed planting pattern for controlling this pest.

[0024] Building upon this foundation, further experiments were conducted to explore the optimal mixing ratio of *Betula spp.* and *Melia azedarach*. At the Dehong Forestry Research Institute base in Yunnan Province, three mixed planting treatments were established, with 1, 3, and 7 *Melia azedarach* trees planted per mu (approximately 0.067 hectares), respectively, and a pure *Betula spp.* forest serving as a control. A point-patterned uniform planting method was adopted, with a spacing of 2 m × 3 m between trees and rows. Ten years after planting, 20 m × 30 m plots were set up for each treatment to investigate the growth of *Betula spp.* and damage caused by the wood-boring moth.

[0025] Example 1 An ecological control method for the wood-boring moth, a stem-boring pest in plantations of Southwest China birch, includes the following steps: The planting density of the Southwest Birch plantation is 2 m × 3 m. In addition to planting Southwest Birch, 7 Chinaberry trees are planted per mu (approximately 0.067 hectares). A dotted and uniform planting method is adopted, with a spacing of 9 m × 10 m between the Chinaberry trees. Traditional methods of tending and fertilization management are used after afforestation. Two years after afforestation, the stand survival rate is 83%, and after 10 years, the stand survival density is 76 trees / mu (approximately 0.067 hectares).

[0026] In this embodiment, the average susceptible rate of birch stands in Southwest China in 2025 was 0.4%, and the average number of insects per susceptible tree was 1.0.

[0027] Example 2 The difference between this embodiment and Embodiment 1 is that the number of chinaberry trees planted is 3 per mu, and the stand density after 10 years is 79 trees / mu.

[0028] In this embodiment, the average susceptibility rate of the Southwest Birch forest in 2025 was 1.9%, and the average number of insects per susceptible tree was 1.0.

[0029] Example 3 The difference between this embodiment and Embodiment 1 is that: the number of chinaberry trees planted is 1 per mu, and the stand density after 10 years is 83 trees / mu.

[0030] In this embodiment, the average susceptibility rate of the Southwest Birch forest in 2025 was 6.2%, and the average number of insects per susceptible plant was 1.1.

[0031] Example 4 The difference between this embodiment and Embodiment 1 is that the planted Southwest Birch plantation is a pure forest, and the stand density is 81 trees / acre after 10 years.

[0032] In this embodiment, the average susceptibility rate of the Southwest Birch forest in 2025 was 16.5%, and the average number of insects per susceptible plant was 2.1.

[0033] Table 2. Statistics on damage caused by the wood-boring moth in *Betula spp.* plots at different densities. The results are shown in Table 2. It is evident that planting just one *Melia azedarach* tree per mu (approximately 0.067 hectares) reduced the infestation rate of *Birchia australis* from 16.5% to 6.2%; while planting seven trees evenly per mu reduced the infestation rate to 0.4%, with only one insect found per infected tree. Therefore, establishing *Birchia australis* plantations with just seven trees per mu effectively controls the wood-boring moth, forming a highly efficient and safe new biological control strategy.

[0034] In summary, this application provides an environmentally friendly and sustainable method for controlling the wood-boring moth, a stem-boring pest, through the rational intercropping of *Betula spp.* and *Melia azedarach*. This method, relying on scientific tree species configuration and density control techniques, achieves long-term suppression of the wood-boring moth population in *Betula spp.* plantations at a relatively low cost, thereby enhancing stand stability, improving timber quality, promoting the sustainable management of high-quality *Betula spp.* plantations, and ensuring a continuous supply of high-quality precious timber.

[0035] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of the claims of this patent application.

Claims

1. An ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, characterized in that, During the construction of Southwest China Birch plantations, a mixed planting pattern of Southwest China Birch and Chinaberry is established to form a biological barrier that interferes with the development and reproduction of the wood-boring moth, thereby achieving ecological control of the wood-boring moth in the Southwest China Birch plantation.

2. The ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, as described in claim 1, is characterized in that... Chinaberry is planted in a dotted, evenly spaced pattern with Southwest birch to form Southwest birch plantations.

3. The ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, as described in claim 1 or 2, is characterized in that... The planting density of Southwest birch plantations is 111-167 trees per mu (approximately 0.067 hectares), with a spacing of 2 m × 2-3 m between adjacent trees. The planting density of Southwest Birch is 101-162 trees per mu; the planting density of Chinaberry is 5-10 trees per mu, and the spacing between the Chinaberry trees is 8-10 m × 8-12 m.

4. The ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, as described in claim 3, is characterized in that... The planting density of chinaberry is 6-8 plants per acre.

5. The ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, as described in claim 3, is characterized in that... The spacing between the rows of chinaberry trees is 9 m × 10 m.

6. The ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, as described in claim 3, is characterized in that... The spacing between adjacent plants is 2 m × 3 m.

7. The ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, as described in claim 1, is characterized in that... Neem germplasm with a neem content of more than 0.2% in the fruit was selected.

8. The ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, as described in claim 1, is characterized in that... The Southwest Birch and Chinaberry were mixed species of the same age.

9. The ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, as described in claim 1, is characterized in that... The Southwest Birch and Chinaberry were planted simultaneously during afforestation and were of the same age in a mixed species.

10. The ecological control method for the wood-boring moth, a stem-boring pest in Southwest China birch plantations, as described in claim 1, is characterized in that... The flowering period of the chinaberry coincides with the emergence, mating, and oviposition period of the wood-boring moth. The active substances released by the chinaberry flowers can effectively inhibit the establishment of the wood-boring moth population by interfering with olfactory localization, repelling adult moths, and inhibiting their development and reproduction. The chinaberry fruits, whether left on the tree or rotting on the ground, continuously release active substances, affecting the emergence, mating, and oviposition activities of the wood-boring moth.

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