Forestry Wasteland

Eucalyptus Myths and Realities:

Eucalyptus is water- intensive and destroys the soils and the underground water table:

• Studies have shown that Eucalyptus consumed 0.48 litres of water to produce a gram of wood, compared to 0.55, 0.77, 0.50 and 0.88 litre per gram for siris, shisham, jamun and kangi respectively. Thus, Eucalyptus is more water efficient than many indigenous species. However, the mean annual growth of Eucalyptus is about 8 cum/ha - 40 cum/ha, as compared to the average of 0.50 cu m/ha for indigenous trees. Being much faster in growth; the very reason for which the species was introduced in the country; the water and nutrient absorption of the tree is much more than the slow growing indigenous trees.

The drought hardiness of the species comes from the fact that Eucalyptus has deep rooted system and an ability to absorb water even at higher moisture tension level, than many other mesophytes plants. E. tereticornis planted in arid and semiarid areas of Portugal 15 years back, have shown no evidence of soil degradation over the years

However, though Eucalyptus is an excellent industrial species, providing timber for poles, pulp and fuelwood, it cannot be used as fodder plant and provide other non-timber uses, limiting its role as a social forestry tree. Thus, plantations of eucalyptus may be limited as industrial plantations with management regime drawn parallel to any intensively produced crop.

1.0 Introduction :

1.1 Eucalyptus belongs to the family Myrtaceae with about 300 species of the genus. The species is one of the fastest growing trees in the world and many species attain great heights. Eucalyptus amygdalin is the tallest known tree with specimens attaining a height of as much as 480 feet.

1.2 Basically, a native of Australia and Tasmania, Eucalyptus was introduced in India, by the British in 1843 in Nilgiri Hills as an experiment to find high yielding species for fuel and timber. It soon became a favoured species for the foresters/ commercial plantations, owing to its fast growth, non exacting, non- browseable and drought resistant nature and adaptability to a variety of agroclimatic conditions.

1.3 Eucalyptus is popularly known as gum tree, red iron tree, nilgiri or safeda. Many fast growing species suitable for commercial cultivation in India have been identified. Eucalyptus tereticornis and E. grandis are important commercial species with a clean straight bole and compact crown. Hybrid eucalyptus (combination to E. tereticornis and E. grandis /E. urphaylla/ E. camaldulensis) has shown greater vigour and drought and insect resistant characters in the field conditions and are preferred planting stock for commercial plantations.

2.0 Botanical Features :

2.1 Eucalyptus is a fast growing, medium- sized to tall tree attaining 20-50m in height and upto 2m in diameter. The tree has a deep tap root system with mycorrhizal associations which increases its ability to draw nutrients and water. The tree has a smooth silvery white stem. The leaves are leathery in texture, hang obliquely or vertically and are studded with glands containing aromatic oil. Flowering takes place during July-August. Flowers in bud are covered with a cup- like membrane (whence the name of the genus, derived from the Greek 'eucalyptos' meaning- 'well covered'), which is thrown off as a lid when the flower expands. The fruiting occurs during September - October. The fruits are surrounded by a woody, cup-shaped receptacles and contain numerous minute seeds.

3.0 Silvicultural Characteristics :

3.1 Eucalyptus is versatile, fast growing and strongly coppicing tree possessing a wide range of soil and climatic adaptability. E.tereticornis has the most extensive latitude range (9-380S) of any species in the genus. Basically a light demander, the growth of the species is very much reduced under shade. Eucalyptus is known for its drought hardiness, although annual rainfall of 800 mm is preferred. The species is also moderately salt tolerant and relatively fire resistant. Eucalyptus is generally regarded as frost sensitive, though in Uruguay, E. tereticornis has known to come up with reasonable success in regions where unseasonal frost is likely to occur. The species is known to suffer cholrosis and die-back due to the reduced iron absorption in alkaline soils.

3.2 The species grows under a wide range of climatic/soil conditions from warm to hot, sub humid to humid and from good to degraded soils. The range of agro-climatic conditions of the species ( E. tereticornis) is given as under:

Climate

• Altitude range : 0 - 1000 m above sea level.
• Mean annual rainfall : 500 - 3000 mm
• Rainfall regime : summer, winter, bimodial: uniform
• Dry season duration : 0 - 8 months
• Mean annual temperature : 10 - 27 0C
• Mean maximum temperature of hottest month : 22 - 42 0C
• Mean maximum temperature of coldest month : -2 - 19 0C
• Absolute minimum temperature : > -80 C ( data for upper limit NA)

Soil and Physiography

• Soil texture : light, medium, heavy
• Soil drainage : Free, seasonally waterlogged
• Soil reaction : acidic, neutral
• Special soil tolerances : saline
• Soil types : alluvial soils, gravely soils, ferral soils, red soils, sandy soils

4.0 Nursery practices:

4.1 Eucalyptus can be easily propagated from seeds, as well as, through vegetative propagation by cuttings (clonal propagation). On an average, there are about 642,000 viable seeds per kilogram of seed and chaff mix. Dry seeds at 5-8% moisture content, can be stored in air tight containers under refrigerated conditions (3-5 0C) for more than 10 years without losing its viability.

4.2 Under nursery conditions, seeds are sown on raised beds under shade. Addition of mycorrhiza innoculum to the nursery soils by adding soil from natural eucalyptus forest is highly beneficial for establishment and growth of the plants. No pre-sowing treatment is required. Rapid and complete germination is achieved under moist, warm (25 - 35 0C) conditions in presence of light. Seedlings are pricked out and transferred to polybags at the second leaf -pair stage i.e. about 6 weeks from sowing. Seedlings are planted out in the field when they reach a height of about 25 cm i.e. about 3-5 months after sowing. This should coincide with the onset of monsoon season.

4.3 Plants at nursery stage are highly susceptible to damping off and other fungal diseases, which can be limited by strict attention to hygiene, reducing watering and shade and allowing good ventilation.

5.0 Cultivation practices

5.1 Eucalyptus, generally raised for industrial plantations - mainly pulpwood, firewood or poles, are maintained with a shorter rotation of 5-7 years. For commercial plantations, intensive site preparation by ploughing or deep ripping on compact sites, is beneficial. On wet sites moulding should be adopted to improve root aeration and provide well-drained condition that facilitate planting. Spacing adopted is 2m x 2m or 1.5 m x 1.5 m (high density plantations). In case, crops are cultivated between the rows (agroforestry), wider spacing of 4m x 2m ; 6m x 1.5m or 8m x 1m are recommended. Nursery raised seedlings/plantlets in polybags may be planted at the onset of monsoons, in pits of 45 cm x 45 cm x45 cm. Organic manure mixtures along with fertilizers containing 25g of NPK (3:2:1) and 50 g of phosphate should be applied in the planting pit at the time of planting. Protective irrigation is essential, in case of monsoon failure, in the first two years of plantation. Eucalyptus is intolerant to shade and does not compete well with grasses for water and nutrients, thus 2-3 hand weeding and soil working in the initial stages are essential.

5.2 Owing to its fast growth, Eucalyptus is a heavy feeder and requires supplements in form of organic and chemical fertilizers in successive years. Deficiency of Nitrogen in soils is a limiting factor for growth and can reduce the yield by 60%. For maintaining the soil fertility, it is advisable to raise Eucalyptus trees with legumes as an intercrop.

5.3 Harvesting is done by clear felling the stand in 6-7 year. Once the tree is felled, the stump throws many coppice shoots. These should be singled out to keep only one vigorous stem per stump, which will form the second crop. It is advisable to change the planting stock after the second harvest, as there is loss in vigour in coppice from the third coppice onwards.

6.0 Pest and diseases:

6.1 One of the most serious diseases of E. tereticornis is canker caused by fungus, Corticium salmonicolour known as pink disease. Other fungal pathogens known to cause damage include, Ganaderma lucidium, Endothia gyrosa and Cylindrocladium spp. Cylindrocladium clavatum has been recorded to cause seed rot, seedling blight and seedling wilt of E. tereticornis in Punjab. Other potentially serious diseases are web blight (Rhizoctonia solani) in the nursery and stem canker caused by Cryphonectria and Cytospora eucalyptiocola which can cause heavy mortality.

6.2 Among insects, ceranbycis beetle, Celstems scabrator is reported to attack young plants in plantations. Subterranean termites are reported to damage seedlings and young plants of the species.

7.0 Yield:

7.1 The mean annual increment (MAI) in volume overbark of E. tereticornis on medium quality sites at age 8-10 years is about 15 cu m/ha. A review of the performance of the species (E. tereticornis) from 8 years old plantations, through out India showed a MAI of 1.3 - 19.8 cu m/ha depending on stocking and site quality. Highest wood yield of 105 tonnes/ha in five years has been reported in red sandy clay loam soils, under irrigated conditions in Karnataka.

7.2 On an experimental scale, the best provenances on the best sites in Bangladesh yielded over 60 cu m/ha/year after five years, at a planting rate of 10,000 stems/ha. Under special trials in China, MAI at 5.5 years of age for E. tereticornis was 11.3 cu m/ha in Guangxi provenance, although the better performing proveniences reached 26.6 cu m/ha in 4.4 years.

7.3 The sale price of well grown Eucalyptus tree after 7 years is about Rs. 100-150/per bole. The sale price of wood at the farm gate varies from Rs. 800 - Rs.1000/ metric tonne.

8.0 Commercial uses of Eucalyptus :

• Eucalyptus is one of the fastest growing trees and is an excellent timber for paper and pulp, particleboard and hardboard industries.
• It is also an excellent source of fuelwood and charcoal.
• Eucalyptus wood is also used for light and heavy construction, railway sleepers, bridges, piles, poles and mining timber.
• Indian Standards are available for use of E. tereticornis timber, after treatment, for door frames, window shutters, furniture, cabinet, tool handles, packing cases and crates.
• Leaf extracts of the species have pesticidal properties and can be promoted as a biopesticide.
• The leaves of the species are rich in essential oils, that have many medicinal uses. Eucalyptus globulus can be raised commercially for Eucalyptus oil.
• E. tereticornis is a major source of pollen in apiculture and produces a medium amber honey of distinctive flavour.
• The wood and bark of the tree have a tannin content of 6-12% and 3-15% respectively, though not used as a commercial source of tannin.
• Eucalyptus is a large ornamental tree suitable for parks and avenue plantations.
• The tree may be used as an agro-forestry species. Eucalyptus in combination with pineapple have given excellent results in China.
• The tree species can be effectively used for regeneration of denuded lands and prevention of soil erosions in drought -affected areas.

9.0 Unit cost and Economics :

9.1 Unit cost for raising Eucalyptus under high density plantations (1.5m x 1.5m) has been worked out to - Rs. 50800/- per hectare. Considering harvesting at the age of 7 years, with a sale price of Rs. 80/pole and fuelwood @ Rs. 500/MT, the IRR works out to 36%. The details of techno-economic parameters and economics are furnished below. The investment has been found to be technically feasible, financially viable and bankable.

Unit Cost for raising Eucalyptus hybrid in 1 ha. of wasteland

Spacing : 1.5m x 1.5m.                                                                 Avg. wage rate Rs. 66 per Man Day

No. of plants per ha. - 4444                                                         Interest on term loan 12%

Mortality replacement : 20%                                                        Margin : 10% of the unit cost

Other expenditure:

Annual Maintainace cost of Rs. 1000/year towards fertilization/manuring.

Harvesting cost in 7th and 14 th years : Rs. 10,000 /- and 8,000/- respectively.

Pruning (of coppice) in the 8th year: Rs. 1000/-

Yield and Income per hectare :

Income and expenditure Statement

NPV of costs : 50625

NPV of benefits :144244

NPV: 93619

BCR: 2.85 : 1

IRR: 36.37%

Repayment

Repayment period : 7 years with 6 years moratorium

10.0 Forward and Backward Linkages:

10.1 The planting stock and technical guidance for commercial plantations of Eucalyptus is available from the Forest Departments, Forest Research Institutes, Agricultural Universities/ Research Institutes and Wood- Based User Industries.

10.2 Eucalyptus is one of the most popular raw materials for paper and pulp, particleboard and hardboard industries and also an excellent source of fuelwood and charcoal. Many wood-based industries have tie up arrangement with farmers/ entrepreneurs for raising Eucalyptus plantation for their consumption. Market for the species is, thus, not a problem, if cultivated with proper tie-ups. List of important wood based industries in the country is listed in Annexure.

11.0 Repayment :

11.1 Repayment of the bank loan can be made in 7 years with 6 years' moratorium.

12.0 Rate of Interest, Margin and Security :

12.1 With deregulation of interest rates, the rate of interest charged to the ultimate borrower is decided by the financing banks. Margin money and Security may be charged by the bank as per the instructions issued by the RBI/NABARD from time to time.

13.0 NABARD Refinance :

13.1 In tune with the National priorities, NABARD extends refinance support for promoting wasteland development/ agro-forestry through Eucalyptus cultivation at a concessional rate of interest.

Annexure II

Important Wood Based Industries in India