Chukrasia Tabularis (Mahogany or Indian Redwood or Toona Ciliate) | Forestry Optional for UPSC IFS

Introduction of Chukrasia Tabularis:

- Chukrasia tabularis, commonly known as Chittagong wood or Indian mahogany, is a deciduous tree species native to Southeast Asia.

- It is highly valued for its timber, which is used in furniture making, construction, and other applications.

- Silviculture refers to the cultivation and management of forests, including the growth and development of trees like Chukrasia tabularis.

Taxonomy of Chukrasia Tabularis:

- Kingdom: Plantae

- Phylum: Angiosperms

- Class: Eudicots

- Order: Sapindales

- Family: Meliaceae

- Genus: Chukrasia

- Species: Chukrasia tabularis

Phenology of Chukrasia Tabularis:

- Chukrasia tabularis is deciduous, shedding its leaves in the dry season.

- Flowering: Typically, it flowers during the hot and dry months, often in late winter or early spring.

- Fruiting: The fruiting season typically follows flowering, with fruits developing during the late spring to early summer.

Ecology of Chukrasia Tabularis:

- Habitat: Chukrasia tabularis is commonly found in deciduous and semi-evergreen forests in tropical and subtropical regions.

- Soil Preferences: It prefers well-drained soils and is often found along riverbanks and in lowland areas.

- Wildlife Interaction: The tree's fruits are a food source for various wildlife species, including birds and mammals.

- Growth Characteristics: It can reach heights of 25-30 meters and has a straight, tall trunk with a relatively narrow crown.

Origin of Chukrasia Tabularis:

- Chukrasia tabularis is native to South Asia, particularly found in countries like India, Sri Lanka, Bangladesh, Myanmar, and Thailand.

- It has been cultivated in other parts of the world as well, including Africa and Southeast Asia.

Natural Distribution of Chukrasia Tabularis:

- In India, it is found in various states, including Assam, West Bengal, Odisha, Andhra Pradesh, and Tamil Nadu.

- It also grows in the Terai region of Nepal and Bhutan.

- The species is widely distributed throughout Southeast Asia, including Thailand, Myanmar, and parts of Malaysia.

- Its natural range extends into Sri Lanka and Bangladesh.

Characteristics of Chukrasia Tabularis:

- It is a large deciduous tree that can reach heights of up to 30 meters.

- The bark is grayish-brown and rough, with vertical fissures.

- The leaves are compound, pinnate, and alternate, with 5-9 leaflets.

- The flowers are small and greenish-white, arranged in panicles.

- The fruit is a capsule that contains winged seeds.

Propagation of Chukrasia Tabularis:

1. Seed collection:

- Collect mature seeds from healthy and vigorous Chukrasia Tabularis trees.

- Ensure that the seeds are fully developed and have a good chance of germination.

2. Seed treatment:

- Soak the seeds in water for 24 hours to soften the seed coat and enhance germination.

- Alternatively, scarify the seeds by gently rubbing them with sandpaper to break the hard seed coat.

3. Seed sowing:

- Prepare a well-draining seedbed or seed trays with a mixture of soil and organic matter.

- Sow the treated seeds at a depth of 1-2 cm and cover them lightly with soil.

- Maintain adequate moisture levels in the seedbed to promote germination.

4. Germination and seedling care:

- Chukrasia Tabularis seeds usually germinate within 2-4 weeks.

- Once the seedlings emerge, provide them with partial shade to protect them from direct sunlight.

- Regularly water the seedlings to keep the soil moist but not waterlogged.

- Protect the young seedlings from pests and diseases by applying appropriate measures.

5. Transplanting:

- When the seedlings reach a height of 15-20 cm and develop a strong root system, they can be transplanted to their permanent location.

- Choose a site with well-draining soil and sufficient sunlight for optimal growth.

- Dig a hole slightly larger than the root ball of the seedling and carefully place it in the hole.

- Backfill the hole with soil, firm it gently around the seedling, and water thoroughly.

6. Maintenance and growth:

- Provide regular watering during dry periods to ensure proper growth and establishment.

- Apply a balanced fertilizer to promote healthy foliage and root development.

- Prune any damaged or diseased branches to maintain the overall shape and health of the tree.

- Monitor for pests and diseases and take appropriate measures to control them.

- Regularly mulch around the base of the tree to conserve moisture and suppress weed growth.

Seed Treatment for Chukrasia Tabularis:

1. Scarification:

- Scarification involves mechanically altering the seed coat to improve water absorption and promote germination.

- In Chukrasia tabularis, scarification can be achieved by nicking or scratching the seed coat with a sharp tool.

2. Stratification:

- Stratification is a cold treatment method that simulates winter conditions to break seed dormancy.

- Chukrasia tabularis seeds can be stratified by storing them in a cool, moist environment for a specific period.

3. Pre-soaking:

- Pre-soaking seeds in water helps to soften the seed coat and initiate germination.

- Chukrasia tabularis seeds can be soaked in water for a predetermined duration before sowing.

4. Hot Water Treatment:

- Hot water treatment involves immersing seeds in hot water to kill pathogens and pests while maintaining seed viability.

- Care should be taken to use the correct temperature and duration for Chukrasia tabularis seeds to prevent damage.

5. Chemical Treatments:

- Chemical treatments can include the use of fungicides and insecticides to protect seeds from fungal infections and insect damage.

- Ensure the safe use of appropriate chemicals and follow recommended dosages.

6. Smoke or Smoke Water Treatment:

- Some tree species, including Chukrasia tabularis, benefit from exposure to smoke or smoke water, which can break seed dormancy.

- Smoke treatments mimic natural wildfire conditions.

7. Imbibition Enhancers:

- Imbibition enhancers, such as gibberellic acid or cytokinins, can be applied to seeds to promote water uptake and germination.

- These plant growth regulators are often used in controlled conditions.

8. Cold Storage:

- Storing seeds at low temperatures can help maintain their viability and prevent premature germination.

- Chukrasia tabularis seeds can be stored in a seed bank or cold storage facility.

9. Seed Coating:

- Seed coating involves applying a protective layer, often with nutrients and beneficial microorganisms, to improve seedling establishment.

- Customized seed coatings can be designed for Chukrasia tabularis to enhance soil interaction and nutrient uptake.

10. Mechanical Scarification Machines: For large-scale silviculture projects, mechanical scarification machines can be used to efficiently scarify Chukrasia tabularis seeds.

Chukrasia Tabularis: Rotation Age, Spacing, Tending Operations and Yield

Rotation Age:

- The rotation age refers to the number of years it takes for Chukrasia Tabularis trees to reach maturity and be ready for harvesting.

- The rotation age for Chukrasia Tabularis is typically around 25-30 years.

- This means that the trees are allowed to grow for a considerable period before they are harvested for their timber.

Spacing:

- Spacing refers to the distance between individual Chukrasia Tabularis trees when they are planted.

- The spacing of Chukrasia Tabularis trees can vary depending on various factors such as soil fertility, climate, and intended use.

- Generally, a spacing of 3-4 meters between trees is recommended to allow for optimal growth and development.

Tending Operations:

- Tending operations involve various activities carried out to ensure the healthy growth and development of Chukrasia Tabularis trees.

- These operations may include weeding, pruning, thinning, and pest control measures.

- Weeding helps to reduce competition for nutrients and sunlight, while pruning and thinning help to shape the trees and promote better timber quality.

- Pest control measures are essential to protect the trees from insect infestations and diseases.

Yield:

- The yield of Chukrasia Tabularis refers to the amount of usable timber that can be obtained from a given area of plantation.

- The yield can vary depending on factors such as tree density, growth conditions, and management practices.

- On average, Chukrasia Tabularis can yield around 10-15 cubic meters of timber per hectare.

- Proper management practices, including regular tending operations, can help maximize the yield of Chukrasia Tabularis plantations.

Soil Requirements for Chukrasia Tabularis:

- Chukrasia Tabularis prefers well-drained soils.

- It can tolerate a wide range of soil types, including sandy, loamy, and clayey soils.

- The tree can grow in both acidic and alkaline soils.

- It is commonly found in areas with fertile soils.

Climate for Chukrasia Tabularis:

- Chukrasia Tabularis is native to tropical and subtropical regions.

- It thrives in areas with a warm and humid climate.

- The tree can tolerate high temperatures, ranging from 20 to 40 degrees Celsius.

- It requires a minimum annual rainfall of 1000-2000 mm for optimal growth.

- Chukrasia Tabularis can withstand short periods of drought but prefers moist conditions.

- It is sensitive to frost and cannot survive in areas with prolonged cold temperatures.

Silvicultural Characters of Chukrasia Tabularis:

1. Growth habit:

- Chukrasia tabularis is a medium-sized to large deciduous tree.

- It has a straight and cylindrical bole with a clear and branch-free trunk.

- The tree can reach heights of up to 30-40 meters.

2. Crown characteristics:

- The crown of Chukrasia tabularis is broad and spreading, providing good shade.

- It has a dense foliage cover with pinnately compound leaves.

3. Bark:

- The bark of Chukrasia tabularis is smooth and grayish-brown when young, becoming rough and fissured with age.

4. Leaves:

- The leaves are alternate, compound, and pinnate, with 5-9 leaflets.

- Each leaflet is ovate-lanceolate in shape, with a serrated margin.

5. Flowers:

- Chukrasia tabularis produces small, yellowish-white flowers in terminal panicles.

- The flowers are bisexual and have a pleasant fragrance.

6. Fruits:

- The tree bears small, round, and woody capsules that contain winged seeds.

- The capsules turn brown when mature and split open to release the seeds.

Nursery Techniques for Chukrasia Tabularis:

1. Seed collection and storage:

- Collect seeds from mature trees during the fruiting season.

- Clean and dry the seeds before storage.

- Store the seeds in a cool and dry place to maintain viability.

2. Seed treatment:

- Soak the seeds in water for 24 hours to enhance germination.

- Scarify the hard seed coat by rubbing or nicking it with a knife.

- Treat the seeds with a fungicide to prevent fungal infections.

3. Seed sowing:

- Sow the treated seeds in well-drained nursery beds or containers.

- Cover the seeds with a thin layer of soil or sand.

- Maintain adequate moisture and provide shade to protect the seedlings.

4. Seedling care:

- Water the seedlings regularly to keep the soil moist but not waterlogged.

- Protect the seedlings from direct sunlight and strong winds.

- Control weeds and provide occasional fertilization to promote healthy growth.

5. Transplanting:

- Transplant the seedlings to polybags or larger containers when they reach a suitable size.

- Ensure proper spacing between seedlings to allow for their growth.

- Harden off the seedlings before planting them in the field.

6. Field planting:

- Select a suitable site with well-drained soil and sufficient sunlight.

- Dig pits or trenches for planting, ensuring proper spacing between trees.

- Plant the seedlings carefully, ensuring that the root collar is at ground level.

Silvicultural Techniques for Chukrasia Tabularis:

1. Site Preparation:

- Clearing the site of competing vegetation and debris.

- Ensuring proper drainage and soil preparation.

2. Planting:

- Selecting healthy seedlings from reliable sources.

- Digging appropriate-sized holes for planting.

- Ensuring proper spacing between seedlings.

3. Pruning:

- Removing lower branches to promote straight stem growth.

- Pruning dead or diseased branches for overall tree health.

- Pruning to maintain desired crown shape.

4. Thinning:

- Removing some trees to reduce competition and improve growth of remaining trees.

- Thinning to maintain appropriate spacing between trees.

- Thinning to enhance overall stand health and vigor.

5. Fertilization:

- Applying appropriate fertilizers to improve nutrient availability.

- Fertilizing to promote healthy growth and development.

- Following recommended fertilization schedules.

Silvicultural Systems for Chukrasia Tabularis:

1. Clearcutting:

- Removing all trees in a designated area.

- Regenerating the stand through natural or artificial means.

- Suitable for Chukrasia Tabularis when it is the dominant species.

2. Shelterwood:

- Gradually removing older trees in a series of cuts.

- Providing shade and protection for younger Chukrasia Tabularis trees.

- Promoting natural regeneration and maintaining a continuous forest cover.

3. Selection:

- Selectively harvesting individual trees or small groups of trees.

- Promoting a diverse age structure and species composition.

- Suitable for Chukrasia Tabularis when it is part of a mixed-species forest.

4. Coppice:

- Cutting the tree at ground level to stimulate regrowth from the stump.

- Utilizing the ability of Chukrasia Tabularis to resprout vigorously.

- Suitable for producing multiple stems and fuelwood.

5. Agroforestry:

- Integrating Chukrasia Tabularis with agricultural crops or livestock.

- Providing shade, timber, and other benefits while maintaining agricultural productivity.

- Suitable for small-scale farming systems.

Economic Importance of Chukrasia Tabularis:

- Timber: Chukrasia Tabularis is highly valued for its timber, which is used in the construction industry for making furniture, doors, windows, and other wooden products.

- Plywood: The wood of Chukrasia Tabularis is also used in the production of plywood, which is widely used in the manufacturing of furniture, cabinets, and other wooden structures.

- Veneer: The species is known for its attractive grain pattern, making it suitable for producing veneer used in decorative applications.

- Medicine: Various parts of Chukrasia Tabularis, such as the bark and leaves, have medicinal properties and are used in traditional medicine for treating ailments like fever, diarrhea, and skin diseases.

- Environmental Benefits: Chukrasia Tabularis helps in soil conservation, erosion control, and provides shade and habitat for wildlife.

Natural Regeneration Methods for Chukrasia Tabularis:

1. Seed Dispersal:

- Chukrasia tabularis produces winged seeds that are dispersed by wind.

- The seeds are lightweight and can be carried over long distances.

- Wind dispersal allows for the colonization of new areas and promotes genetic diversity.

2. Animal Dispersal:

- Some animals, such as birds and mammals, may consume the fruits of Chukrasia tabularis and disperse the seeds through their droppings.

- This method of dispersal helps the seeds to be spread in different locations, increasing the chances of successful germination and establishment.

3. Self-seeding:

- Chukrasia tabularis has the ability to self-seed, where the seeds fall near the parent tree and germinate.

- This method ensures the continuity of the species in the same area and can lead to the formation of dense stands of Chukrasia tabularis.

4. Regeneration through root suckers:

- Chukrasia tabularis can also regenerate through root suckers, which are shoots that arise from the roots of the parent tree.

- This method allows for the expansion of the existing clumps or stands of Chukrasia tabularis and can occur in response to disturbances such as logging or fire.

5. Regeneration through stump sprouting:

- When Chukrasia tabularis trees are cut down, they have the ability to regenerate through stump sprouting.

- New shoots emerge from the cut stump or the base of the tree, allowing for the regrowth of the tree.

- This method is commonly observed in coppicing, where the tree is cut close to the ground to encourage the growth of multiple stems.

6. Regeneration through rhizomes:

- Chukrasia tabularis can also regenerate through rhizomes, which are underground stems that produce new shoots and roots.

- Rhizomatous regeneration allows for the spread of Chukrasia tabularis in areas with suitable soil conditions and can contribute to the formation of extensive clonal colonies.

Artificial Regeneration Methods for Chukrasia Tabularis:

1. Seed Collection and Storage:

- Collect mature seeds from healthy Chukrasia Tabularis trees.

- Ensure proper cleaning and drying of seeds before storage.

- Store seeds in a cool and dry place to maintain viability.

2. Seed Treatment:

- Conduct pre-sowing treatments like scarification or soaking in water to enhance germination.

- Treat seeds with fungicides to prevent fungal infections.

- Use growth regulators to promote uniform germination and seedling growth.

3. Nursery Techniques:

- Prepare well-drained nursery beds with fertile soil.

- Sow seeds at the recommended depth and spacing.

- Provide adequate irrigation and shade to promote seedling growth.

- Control weed growth through regular weeding.

4. Vegetative Propagation:

- Utilize vegetative propagation methods like stem cuttings or air layering.

- Select healthy and disease-free branches for propagation.

- Apply rooting hormones to enhance root development.

- Provide appropriate environmental conditions for successful rooting.

5. Tissue Culture:

- Establish tissue culture laboratories for mass production of Chukrasia Tabularis plantlets.

- Collect explants from selected elite trees.

- Initiate tissue culture through sterilization and culturing techniques.

- Optimize growth media and conditions for rapid multiplication of plantlets.

6. Planting Techniques:

- Select suitable sites with proper soil conditions and adequate sunlight.

- Prepare the planting holes of appropriate size and depth.

- Transplant seedlings or propagated plants carefully to avoid root damage.

- Provide initial support and protection to young plants.

7. Maintenance and Care:

- Implement regular watering and fertilization schedules.

- Monitor and control pests and diseases through appropriate measures.

- Prune and shape the plants to promote desired growth.

- Conduct periodic thinning to maintain optimum spacing.

8. Monitoring and Evaluation:

- Regularly monitor the growth and health of regenerated Chukrasia Tabularis plants.

- Assess survival rates and growth performance.

- Evaluate the success of different regeneration methods.

- Modify techniques based on observations and feedback for continuous improvement.

Chukrasia Tabularis: Principles Governing the Felling of Trees in Forests

1. Sustainable Forest Management:

- Forests should be managed in a way that ensures the long-term availability of timber resources.

- Felling of trees should be done in a manner that allows for natural regeneration and maintains the overall health and biodiversity of the forest ecosystem.

2. Selective Logging:

- Only mature and fully grown trees should be felled, while younger trees and saplings should be left untouched.

- This practice helps in maintaining the forest structure and allows for the growth and regeneration of new trees.

3. Minimum Diameter Limit:

- Trees below a certain diameter should not be felled to allow them to grow and contribute to the forest's future timber resources.

- This limit varies depending on the species and local forest regulations.

4. Restricted Felling Season:

- Felling of trees should be restricted to specific seasons to minimize the impact on wildlife, nesting birds, and other forest-dependent species.

- This helps in preserving the natural breeding and nesting cycles of various organisms.

Chukrasia Tabularis: Indian Forest Laws Governing Cultivation and Trade

1. Forest Conservation Act, 1980:

- This act aims to conserve forests and wildlife by regulating activities like felling of trees, diversion of forest land for non-forest purposes, and trade in forest produce.

- It prohibits the felling of trees without prior permission from the concerned authorities.

2. Wildlife Protection Act, 1972:

- This act provides protection to wildlife species and their habitats.

- It prohibits the hunting, poaching, and trade of endangered species, including those found in forests like Chukrasia Tabularis.

3. Forest Rights Act, 2006:

- This act recognizes and vests the rights of forest-dwelling communities over forest land and resources.

- It aims to empower these communities in the sustainable management and conservation of forests.

4. Indian Forest Act, 1927:

- This act provides for the regulation of forest produce, transit of timber, and the establishment of forest reserves and protected areas.

- It governs the cultivation, harvesting, and trade of forest products, including Chukrasia Tabularis timber.

Chukrasia Tabularis: Mortality, Pests, Diseases and Their Control

- Mortality: Chukrasia tabularis has a moderate mortality rate. Factors such as poor soil conditions, drought, and extreme temperatures can contribute to tree mortality.

- Pests: Common pests that affect Chukrasia tabularis include defoliating insects like caterpillars and leaf miners. These pests can cause significant damage to the foliage and overall health of the tree.

- Diseases: Chukrasia tabularis is susceptible to various diseases, including fungal infections like powdery mildew and root rot. These diseases can weaken the tree and lead to decline or death.

- Control measures: To control pests, regular monitoring and early detection are crucial. Integrated pest management techniques, such as biological control and targeted pesticide application, can be employed. Disease control involves maintaining proper tree hygiene, improving soil drainage, and using fungicides when necessary.

Tree Improvement for Chukrasia Tabularis:

- Selection: The process involves selecting superior trees with desirable traits as parents for breeding programs.

- Breeding: Controlled pollination is carried out to produce offspring with improved characteristics. This can be done through natural or artificial methods.

- Genetic diversity: Maintaining genetic diversity is important to prevent inbreeding depression and increase the resilience of the species.

- Testing and selection: The offspring are evaluated through field trials and other tests to identify the best-performing individuals for future propagation.

Management of Chukrasia Tabularis:

- Silvicultural practices: Proper management of Chukrasia tabularis involves silvicultural techniques such as thinning, pruning, and coppicing to promote healthy growth and timber production.

- Site preparation: Adequate site preparation, including soil improvement and weed control, is essential for successful establishment and growth of Chukrasia tabularis.

- Planting and spacing: Proper planting techniques and appropriate spacing between trees ensure optimal growth and prevent competition for resources.

- Irrigation and fertilization: Depending on the site conditions, supplemental irrigation and fertilization may be necessary to support tree growth and development.

- Harvesting and regeneration: Harvesting of mature trees should be done selectively, considering sustainable forest management practices. Regeneration methods, such as natural regeneration or planting of seedlings, should be employed to ensure the continuity of the species.

Conclusion:

- Silviculture practices for Chukrasia tabularis involve careful site selection, seed collection, nursery management, plantation establishment, thinning and pruning, and weed and pest management.
- By following these practices, the growth and development of Chukrasia tabularis can be optimized, leading to high-quality timber production and sustainable forest management.