cashew agronomy The tree The cashew-nut tree is a fast grower and an evergreen tropical tree. It grows to a height of 12 m. Blossoming takes place between November and January. Seedling trees flower in the third year after planting. The fruit ripens fully within 2 months. The fruit (nut) The nut is attached to the lower portion of the cashew apple which is conically shaped. The cashew nut (seed) hangs at the bottom of the apple, and is c-shaped. The cashew seed has within the outside shell the edible kernel or nut. In its raw form the cashew kernel is soft, white and meaty. When roasted it changes colour and taste. Salted, it appeals to the palate as the most delicious nut. Cashew apples and cashew nuts are excellent sources of nutrition. The cashew apple contains five times more vitamin C than an orange and contains more calcium, iron and vitamin B1 than other fruit such as citrus, avocados and bananas. Cashew shell oil extracted from the shells is caustic and causes burns on the skin. The mucous membranes of the mouth and throat are severely affected when it comes into contact with shell oil or the irritating fumes emitted during roasting. The oily shell liquid has many uses. Climatic requirements Cashew trees are genuinely tropical and very frost sensitive. The trees grow in a wide spectrum of climatic regions between the 25 °N and S latitudes. Although the cashew can withstand high temperatures, a monthly mean of 25 °C is regarded as optimal. Yearly rainfall of 1 000 mm is sufficient for production but 1 500 to 2 000 mm can be regarded as optimal. The cashew tree has a well-developed root system and can tolerate drought conditions. Rain during the flowering season causes flower abortion due to anthracnose and mildew. During harvesting, while nuts are on the ground, rain and overcast weather causes the nuts to rot or start germinating. Nuts germinate within 4 days when lying on wet soil. Trees grow well at Pongola, Hluhluwe, Mtubatuba and Makhathini where the climate can be described as warm-subtropical. The Natal coastal region north of Empangeni as well as the Pongola valley are suitable areas for cashew production. Regions in the interior, such as Malelane and Hoedspruit, with warm summers and winters are also suitable. In other subtropical regions of South Africa, where the absolute minimum temperature falls below 7 °C, commercial plantings will be at a high risk.

Soil requirements The cashew is a strong plant that is renowned for growing in soils, especially sandy soils, that are generally unsuitable for other fruit trees. For the best production deep, well-drained sandy or sandy-loam soil is recommended. Cashew trees will not grow in poorly-drained soils. Establishment Self-pollination and cross-pollination play an important role in the formation of cashew seed. Seedlings therefore show great variation and no "true to type" trees can be grown from seed. Selected trees should preferably be multiplied by grafting or air layering because vegetative propagation will ensure the best production and quality. Trees that are precocious bearers and grow vigorously are selected. Nuts should weigh between 8 and 9 g with a density of not less than 1,0. Trees with yellow to grey-brown apples have exhibited the most resistance against anthracnose and are associated with the best production. Planting Fresh seeds that sink in water are planted in an upright position in a planting bag containing a loose, sterilised soil mixture. Three to four seeds can be planted directly in the planting hole. The weakest ones are thinned out later and the strongest left to develop further. The seedlings are very susceptible to Phytophthora root rot. The plant bags should be 350 to 400 mm deep, as the tap-root grows very fast and bends around as soon as it touches the bottom. Grafting Two grafting techniques, namely side grafting and wedge grafting are practised with success. Grafting should commence as soon as possible (seedlings of 3-4 months old) and planted out in the orchard to prevent the tap-root from bending. Seedlings Cashew seedlings are grown under shade (45 %) and hardened off before planting in the orchard. It is very important not to disturb the root system during planting. Young trees should be supported for the first 2 to 3 years so that wind will not blow the plants over. Planting distance Planting distances of 8 x 5 m is recommended. The trees grow vigorously in the first 3 years and as soon as the crowns touch each other alternate trees should be removed until the permanent planting distance of 10 to 12 m is reached. Branches hanging on the ground should be removed because they interfere with harvesting. In other parts of the world cashew trees bear well, in spite of the little attention devoted to the orchards. Growth and production of cashew trees can be enhanced by establishing clonal orchards, and improving fertilising and irrigation practices Fertilisation The application of nitrogen and phosphate are important. Approximately 75 g LAN and 200 g superphosphate per year age of the tree is applied annually with a maximum of 750 g LAN and 2 kg superphosphate. Cashew trees are subject to zinc deficiency that can be treated with 200 g zinc oxide/100 l water applied as a leaf spray. Flowering to harvest time Flowering is affected by weather conditions and also varies from tree to tree, but continues for a period of 3 months. High temperatures lead to earlier flowering. Both male and bisexual flowers are borne on one cluster. The flowers are very susceptible to mildew and control thereof on the leaves and flowers is a prerequisite for good production. Pollination is mostly by insects. After pollination it takes 6 to 8 weeks for the fruit to develop. The nut develops first while the apple develops and enlarges only 2 weeks before fruit fall. Nuts should be harvested as soon as possible, especially under wet conditions and should be dried before storage. Irrigation Irrigation is important during establishment of young trees because it doubles the growth tempo of young trees in a dry season. Due to the deep root system the trees can survive several months without irrigation. Mature trees should receive 1 800 l of water per tree every 2 weeks. Weed control Grass strips in the inter-rows between the tree lines are ideal to prevent erosion and should be cut regularly. Processing The objective of cashew processing is to extract the healthy, tasty kernel from the raw nut in the shell. Most modern factories are designed to obtain the maximum number of whole nuts and as much shell oil as possible. Processing can be subdivided into a series of steps. Drying Harvested nuts are dried in the sun for a few days. Properly dried nuts can be stored for 2 years before being shelled. Nuts are roasted to discharge the caustic shell oil and acrid fumes. Hand shelling is impossible if the shell oil has not been removed previously. Kernels must be protected from contamination by the shell oil because it would cause blisters in the mouth and throat when eaten. Before the nuts are roasted they must be soaked in water—the moisture in the shell facilitates the rupturing of the cells containing shell oil and retaining it in the shell. Moisture makes the kernel slightly rubbery and limits breakage of the kernels. The easiest method to wet the shells is to heap the nuts into big piles and to use sprinklers intermittently. Steam may also be used. The simplest roasting method is to heat the nuts for about a minute in an open pan with holes. Acid fumes are released and if the nuts should catch fire the flames can be doused with water. A more efficient method is to use a slanting perforated cylinder that is rotated above a fire. The shell oil flows through the holes in the cylinder and is collected in a catch through. After the roasting process the nuts are dumped into ash or sawdust to remove the excess shell oil still clinging to the shells. Shelling This is the most difficult operation in cashew processing. In India shelling is mostly done by cheap female labour. Shelling is carried out by using special wooden mallets and pieces of bent wire, at a rate of about 200 nuts per hour. Mechanical shelling methods are difficult to design because of the irregular shape of the nut, hardness of the shell and brittleness of the kernel. In some mechanical processing plants compressed air is used to crack the nuts. The latest Windmer and Ernst method is to cut a groove around the shell and to place the shells in a modified centrifuge fitted with metal plates. The nuts are thrown against the plates and cracked by centrifugal forces when the machine spins. It is possible to obtain 85 % whole kernels with this method. Removal of the testa Before the thin, papery seed coat (testa) can be removed, the kernels must be dried. Nuts are dried on big racks in an oven at 70 °c. The testa becomes dry and brittle and is easily removed. The remaining traces of membrane are removed with bamboo knives. Modern factories use electronic machines to detect nuts with pieces of remaining testa which are then sorted and cleaned by hand. Grading Kernels, whole and broken, are sorted into 6 grading schedules. There is only a small demand for broken or dark and unevenly roasted kernels. Packaging Kernels are dried to 3 % moisture content before they are packed. Drying is necessary to extend shelf life and prevent fungal and other infections. Dried kernels do not become rancid. Nut kernels of export quality are vacuum packed in tins. By-products Shell oil represents about a quarter of the mass of an unshelled nut and approximately equal to that of the kernel. This fluid, that is not an oil as the term "shell oil" indicates, but a mixture of anacardic acid and cardol is the main by-product. There are more than 200 registered patents of different uses of shell oil. One of the most important uses is in the manufacture of brake linings. Shell oil is used in the manufacture of numerous materials that have to be resistant to heat, friction, acids and caustic products, for example clutch plates, special isolators, varnish and plastic materials. The wood is insect repellent and used in making book cases and packing crates. The gum is a replacement for gum arabic and used as insect repellent glue in book bindings. In the nut and the apple, a compound has been found that combats tooth decay. The apple is highly perishable but very healthy. It can be eaten fresh or juiced. Syrup, wine, brandy, gin, preserved fruit, pickles and glazed fruit are also made from the cashew apple. In Brazil, fresh cashew-apples are packed in trays and marketed in retail fresh produce outlets. The indigenous people in cashew-producing regions use different parts of the plant such as the leaves, bark, gum, wood, juice and roots for the preparation of local medicines or insect-repellent mixtures. The bark is rich in tannins and is used in leather tanning. The papery seed coat around the kernel can serve as cattle feed. Exports India earns more than 200 million dollars a year by exporting 40 to 50 thousand tonnes of cashew kernels and the country's tradelinks are spread over 40 countries. Cashew is a craze in the United States which is by far the largest buyer. The other major purchasers are the eec countries, Japan, Australia, Canada, Hong Kong, Singapore and the countries in the Middle East. Cashew is an excellent choice to grow around the house as a shade tree with healthy fruit (apple) and nuts. Nuts determined the eating habits of prehistoric people. Along with berries and brook water, nuts followed humanity to civilisation. Cashew nuts are packed with proteins, fats and vitamins to a high degree. Proteins, the tissue builders in our system, constitutes a large proportion of cashew contents. The cashew kernel contains 21 % of vegetable protein. Nutritionally they stand on a par with milk, eggs and meat. It also contains a high concentration of much-needed amino acids.

Passionfruit cultivation

Growing Considerations

Are you considering growing passionfruit? Is it because you would like an endless supply of passionfruit as a dessert topping, or the possible financial return? Here are some key factors that you should consider...

Objectives

• a hobby. 
• a lifestyle - an income but little or no investment return. 
• as an investment.

It has been said that one person can look after 400 plants on a full-time basis. You must have the time to put into the crop i.e. spraying (fortnightly) during the growing season - from January to July depending on your locality, trailing the vines, harvesting the fruit from the ground before they get burnt from the summer sun, cleaning & grading the fruit for sale whether it be for export or the local market. Passionfruit require attention every day during the growing season, not just at weekends.

Key Success Features

The following Key Success Factors must be met for passionfruit growing to be viable:

• the proposed site should ideally be north facing and frost free. 
• passionfruit should be planted in rows running North to South 
• free draining soil - passionfruit do not like "wet feet". 
• adequate shelter established before planting to protect from wind damage. 
• a soil test will determine the nutrients required for ideal growing conditions. 
• adequate rainfall or access to irrigation during the growing period and dry spells. 
• effective plant and machinery for spraying, mowing and other orchard activities. 
• a suitable hygienic area available to clean, grade and pack the fruit. 
• the greatest returns are received from exporting passionfruit. There are many New Zealand and overseas requirements relating to exporting Sub Tropical fruit which growers must comply with. Grower registration, Spray certification etc.

Passionfruit vines require a warm moist environment to thrive. Commercial passionfruit production is only possible in relatively frost free locations. However the vines will tolerate a slight frost of minus 1-2 degrees C for short periods. More severe frosts will kill the growing shoots, cause severe fruit damage and fruit drop.
Your orchard should ideally be established in a deep, well drained sandy loam. Poorly drained soils cause the vines to become susceptible to root disease which can rapidly kill the plants. Where natural drainage is inadequate a suitable drainage system should be installed before planting.

Indicative Set up costs

These can vary depending on the structure used to grow the vines. The following costings (May 2002) relate to the "A" frame structure with the apex being approximately one metre apart from the uprights.
To hold all the above timber in place you will require six 100mm and twelve 75mm (decking nails) galvanised nails for each frame. Eight staples per frame are required to support the wire on the frames.
To anchor the wire at either end of the row you require two deadman (two 1.8m posts) or two screw in galvanised 1.5m anchor.
A coil of 2.5mm galvanised wire coil (to train the vines up between frames - eight wires on each frame for the vines and one just above the posts to carry an irrigation pipe) is required. An average coil of wire is 650 metres in length.
You also have to consider whether you will employ a contractor to ram the posts or dig the postholes yourself. Do you require the services of a fencing contractor, paid per hour, to tension the wires or do you have the necessary skill and fencing equipment to do the job yourself?
Passionfruit Plants propagated by a nursery are sold per plant. You can grow them from seed if you have a plastic house, the time, and allow for the cost of potting mix.

Passionfruit Growing Requirements

Purple passionfruit require a warm, sheltered, frost-free site for a commercial planting to thrive and be profitable. The soil must be free draining as passionfruit are very susceptible to "wet feet" and will succumb to any water-logging of the soil.
Passionfruit will only tolerate light frosts (-1 to -2 degrees C) and heavier frosts can severely damage an orchard. Cold winds can also put passionfruit under severe stress and if winds persist, can introduce an early attack of woodiness virus. The only counter remedy for this virus is total removal of the vine.
Passionfruit vines will grow an a wide range of soils, but good drainage and aeration are essential. A deep drained, friable sandy loam is best. Heavy clay soils are unsuitable. Where natuaral drainage is inadequate a suitable drainage system should be installed before planting. Seek local advice before laying a drainage system.
Planting of a suitable shelterbelt is recommended in all passionfruit growing areas of New Zealand. These should be trimmed every 1-2 years depending on the species selected. Root pruning of the shelterbelt is very important as the roots will quickly invade the orchard and rob the soil of nutrients. This causes the vines to go yellow and the fruit to be small.
Root pruning should be done to a depth of 1m every second year. A root saw is the most effective way of pruning as it stops any rejoining of the roots.

Passionfruit Growing Structures

Being rampant climbers, passionfruit need substantial structures to support the heavy crop loading. The three main trellis structures used by New Zealand's commercial growers are "A" frames, pergola and fence. Many growers have adapted and modified these structures to suit their individual needs.

"A" Frames

As the name suggests, these are fabricated in the shape of an "A" and usually made from timber, but steel can also be used. They need to be strong to support the heavy loading of foliage and fruit.
If using timber, 100mm x 50mm is recommended. The "A" frames are attached to posts 150mm (minimum) in diameter and 1 metre long with 500mm above ground. Row spacings vary, depending on the machinery being used but about 3.5m is recommended.
The short posts are driven into the ground about 6m apart in the row and the "A" frames are attached to these. At each end of the rows, about 2m from the last frame, a 'deadman' is driven to attach the wires (a deadman is a substantial post at least 1.8m long with a small end diameter (SED) of 150mm, driven with 500mm above ground). A galvanised screw anchor can also be used.
Four 12-guage wires are strung each side of the frames and the framework of the vines will be trained to these. The top wire is usually about 2m high for ease of vine handling and each subsequent wire is about 500mm apart. It is important to tie back each end frame to prevent it from collapsing inwards

Advantages

• Fruit only needs picking up once a day
• Reduces the cost of mowing and weeding
• Gives 50 percent more canopy area
• Gives better protection from sunburn
• Fruit gets good spray coverage
• Gives better wind protection

Disadvantages

• More costly to erect both in labour and materials
• Foliage can get very dense in between the A frames
• More training/pruning required to keep gap at top open for sunlight penetration

"Y" Frames

As the name suggests, these are fabricated in the shape of an "A" and usually made from timber, but steel can also be used.Constructed similar to "A" frames, refer above.
The frames are braced between each upright arm which leaves a totally open area between the rows.
This aids the movement of warm air and sunlight and enables spraying to be done by overhead boom to spray downwards to achieve better penetration. Frame bracing can be attached to taller upright row posts, if required.

Pergola

A pergola system consists of 2.4m posts being driven to 2m above ground in rows 4m-5m apart. The posts are 6m apart down these rows. Laminated 100mm x 25mm timber is attached across the rows to the top of the posts and steel can also be used.
A deadman is driven at the end of each row to attach the wires (see A frames) and a screw anchor can also be used. A 12-guage wire is run along the tops of the posts, attached with a staple and fastened off each end to the deadman.
Wires are spaced about 500mm apart across the block and each end pergola has to be tied back to the deadman to stop it collapsing inwards. Some variations of this system are used by some growers to increase cropping area.

Advantages

• Gives good protection from both sunburn and wind
• Fruit needs to be picked up only once a day
• Fruit gets good spray coverage
• Mowing and weeding costs reduced
• Disused kiwifruit structures can be used

Disadvantages

• More costly to erect
• A strict pruning regime required to keep gap at top open for sunlight penetration

Fence

Originally, most commercial passionfruit were grown on the fence system but now this has largely been superseded by the other two systems. A fence is a row of 2.4m posts driven to 2m above ground. Posts are 6m apart down the row and at the end of each row is a deadman or screw anchor (see A frames) for the attachment of wires.
Rows can be 2m - 3m apart depending on the machinery being used. A 12-guage wire is attached at the top of the post and two more wires are run about 700mm apart down the post. There are many variations to this fence system.

Advantages

• Cheaper to erect
• Winter pruning may be quicker

Disadvantages

• Fruit is more exposed to climatic adversities such as wind and hail
• Harder to get good spray coverage on the fruit
• More mowing and weed control required
• Sunburn on fallen fruit more of a problem, fruit needs to be continually collected on sunny days.
• Fruit quality generally inferior to other systems

Diseases

A number of serious diseases can reduce yields and kill passionfruit vines if not controlled.

Grease Spot

This is caused by the bacterium Pseudomonas passiflorae and is one of the most serious diseases of passionfruit in New Zealand. It infects leaves, stems and fruit, leading to severe crop losses and even death of vines.

Symptoms

On leaves, it causes irregular olive-green to brown lesions, often surrounded by a light-yellow halo. If unchecked severe defoliation can result. On the stems of young growth the first signs of infection are small slightly sunken, dark-green, water-soaked spots. These develop into light-brown, markedly depressed areas.
On older wood, symptoms range from small, slightly sunken, smooth, dark-green circular spots, to large, dark-brown, cracked lesions, which may completely girdle shoots and kill vines. Early signs of infection on the fruit are small, dark-green, oily spots. These develop into roughly circular, greasy, or water-soaked patches. Premature fruit drop and fruit decay result. Grease spot is said to be most active in autumn and winter, between March and August. However, a condition known as hard grease spot, also caused by Pseudomonas passiflorae, has become prevalent on passionfruit and is active in summer. The symptoms are similar to ordinary grease spot except that the fruit infections dry out and cause a hard brown patch on the skin, instead of leading to decay. This results in a downgrading of fruit and loss of income.

Bacterial Blast

Blast is caused by a bacterium, Pseudomnas syringae, which is a relative of the grease spot pathogen.

Symptoms and Control

The symptoms of the two diseases are similar, and control measures are the same. Where good control of grease spot is obtained, blast should not be a problem.

Brown Spot

This is a serious fungous disease, caused by Alternaria passiflorae, which affects leaves, stems and fruit. It occurs mainly in spring and early summer.

Symptoms

On leaves, small brown spots appear first. These enlarge, develop a lighter-coloured central area, and become irregular or angular in shape.
On stems, elongated dark-brown lesions appear, usually near leaf axils or where stems have rubbed against the supporting wire. Infection spreads from these points and whenever the stem becomes completely girdled the shoot suddently wilts and fruits collapse.
On fruit, spots first appear as pinpricks, which enlarge into sunken circular lesions with brownish centres. Eventually the rind round the diseased area becomes wrinkled and the fruits shrivel and drop.

Septoria Blotch

Caused by the fungus Septoria passiflorae, this disease attacks leaves, stems and fruit. Even a light infection results in defoliation and premature fall and loss of fruit. The disease is more common during summer and autumn.

Symptoms

On leaves, tiny superficial, irregular, light-brown spots appear, quickly followed by severe defoliation as infection spreads.
On stems, spots similar to those on leaves appear. They become deeply sunken but remain minute.
On fruit, the infection initially appears as small spots, similar to those on the leaves and stems. The spots develop into extensive superficial leasions causing premature drop and fruit decay.

Bitter Rot

The fungus Glomerella cingulata causes this disease and can be responsible for significant fruit loss, especially in hot, humid conditions in the summer months. Infection is facilitated by any damage to the skin of the fruit.

Symptoms

Dark, soft lesions rapidly develop on infected fruit that can colonise whole fruit. Infected fruit will fall to the ground.

Control

The routine protective fungicide programme based on copper sprays will afford protection but under stringent infection conditions may need to be repeated at short intervals in the height of summer.
Picking up and removing infected fruit is a good hygienic practice.

Sclerotinia

Sclerotinia sclerotiorum is the causal pathogen of this disease.

Symptoms

It can affect stems where lesions can enlarge to cause a girdling and collapse of the shoots above the lesion. The hard dark sclerotes which are a means of carrying the fungus over from one season to the next can often be seen in infected shoots.
It can also infect fruit with infections rapidly becoming pale brown lesions that can develop over a whole fruit. With advanced infections a mass of fluffy white fungal growth is produced in which the black sclerotes can be seen. Infected fruit falls to the ground, and the sclerotes will carry the infection potential over to future seasons.
Infection occurs mainly in the November-December period when vines are wet for 16-24 hours and temperatures are in the 15-200C range.

Control

Where Sclerotinia has been a problem application of a suitable fungicide after pruning when the main structure of the plant can be covered is worthwhile.
Orchard hygiene is also important. Infected fruit should be picked up and removed from the orchard, and infected shoots cut out below the lesion and destroyed. This will ensure that the sclerotes are removed and minimise the carryover of infection within the orchard.

Crown Canker

This is a lethal condition of passionfruit, causing sudden wilting, leaf and fruit drop and death. It has been a major factor in limiting the commercial production of passionfruit in New Zealand.
A number of Fusarium species have been isolated from plants suffering from crown canker, the most prevalent of which is Fusarium redolens. Other fungi known to be involved include Fusariumavenaceum, Gibberella baccata, and Gibberella saubinetii.

Symptoms

The condition usually occurs close to ground level, centred on wounds caused by frost, growth cracks, mechanical damage, fertilizer or herbicide burn, or by pest injury such as that caused by slugs or snails. Infections often progress to girdle the stem at or near ground level.

Control

Unfortunately there is no known control for crown canker, so all efforts to reduce the risk of infection are worthwhile. These would include selection of the best sites to minimise frost and weather damage, regular frost protection with bracken fern or similar material each winter, and avoiding injury to the base of the plant by implements, fertilizer or herbicides.
It is also good practice to keep the base of the plant clear of grass and weeds, which favour fungal growth and harbour slugs and snails. Where collars are placed around stems to protect against herbicide damage, slug pellets placed inside the collar will help control these pests.
Plants suffering from crown canker should be carefully removed and destroyed by burning.

Phytophthora Root Rot

Phytophthora is known to affect passionfruit. In New Zealand two species are mainly involved, Phytophthora cinnamomi is prevalent in summer and autumn, and Phytophthora megasperma is prevalent in the spring.Both fungi can cause the death of vines, but it is thought that the stress and damage they often cause open the way for invasion by Fusarium and death of the plant from crown canker.

Control

Improving drainage is one way to reduce the risk of Phytophthora infection.

Thielaviopsis Root Rot

This is another fungous disease which can affect passionfruit growing on heavy soils. It is caused by Thielaviopsis basicola.

Symptoms

Intected plants are unthrifty, with poor-coloured foliage. The roots show signs of decay and are often blackened.

Control

With mild infections sometimes a severe pruning to balance the top growth with the loss of roots can keep the plants going, but severely infected plants should be removed and replaced.

Woodiness

Woodiness may be caused by the cucumber mosaic virus, the passionfruit woodiness virus (a member of the potato virus Y group) or alfalfa mosaic virus, or a combination of these or possibly other viruses as well.

Symptoms

On leaves it causes yellow spots, flecks or mottling, and there is crinkling or distortion. It also shows as shortened internodes on the stems, bunching of foliage and stunted growth. Symptoms are most apparent during late autumn, winter and early spring.
On fruit it causes thick, hard, distorted woody rinds, often with characteristic scabs and cracks. Pulp yields are much reduced.

Control

Plant only virus-free plants and remove and replace severely infected vines. The disease is transmitted by aphids and possibly also by pruning tools. Once vines become infected there is no known control. Obviously infected plants should be rogued out and destroyed. Virus symptoms are minimised by promoting vigorous vine growth and where necessary aphids should be rigorously controlled.
In older blocks or where some vines may be infected, disinfecting pruning tools between vines or parts of a block could be worthwhile. This can be achieved by dipping pruning tools in a 1% solution of hypochlorite (bleach) for a few seconds, neutralise by a dip in vinegar and protect tools with a spray of CRC or Valvoline.

how to planting rubber

 

Land Preparation for Rubber Planting

This should be completed before rainy season
The due period-(November - February)
a). Removal of the entire trees of the land

If it is a replanting land, points of the died trees of the old stand should be demarcated before removing the trees.
The trees must be uprooted enabling to curtail the risk of spreading the white root disease to the new planting.

b). Soil Conservation Measures and Construction of Fences.
In line with the location of the land, one or a certain number of following soil conservation measures should be adopted.
 Agricultural Practices – Contour Planting.
 Weeds on embankments and on areas close to the fences should not be completely removed and they should be kept under control..

 The due period-(January - March).
c). Biological Practices
Cover Cropping – Cover Crops such as Mucuna, Pueraria, Desmodium are suitable for this purpose.
 Citronella grass can be grown thickly along the Contour Hedges.
Mulching – Paddy straw or Crotalaria, Flemingia and Gliricidia as green manure can be used for this purpose.
d). Mechanical Practices Construction of Drains - Normally, natural drain lines already indicated in the land can be used as main drains and the distance between two drains should be approximately 60 m. The lateral drains should be on the Contour lines with a slope of 1 in 120. The spacing of lateral drains can bring the drain lines within 1.5-1.8 of the planting rows..
 Construction of Stone Terraces – It is opportune to construct contour stone terraces on very rocky land, where it is impossible to cut continuous lateral drains. In the construction of stone terraces, the upper side of the terrace should be on a perfect Contour and the lower side of the terrace should be wider than the top.

The number of trees to be planted and planting distances.

 Normally, around 510-520 rubber plants per hectare can be planted.
The due period-( March).
Planting Distances- Avenue type planting 3.5 x 5.5 m.
Square planting 4.3 x 4.5 m.
The above second method should be followed, if intercropping is to be undertaken. Further, changing the planting distances between replanting cycles and disuse of holes of the old rubber stand for replanting has helped to reduce the incidence of White Root disease in the replanting.

Planting.

Planting should be done with the onset of the monsoon rains. The major rainy season falls in May-June. In the Districts of Monaragala, Badulla, Ampara and Hambantota, planting is undertaken during the period of North-East rainy season that falls in October.
The due period- (May - June),(October - November)
a). Selection of a suitable plant
It is more opportune to plant young buddings. Because, it shows a rapid and fast growth as the root system of the plant is not damaged in the events of production and planting of young buddings. The budded rubber plants with 2 leaf whorls including a hardened top whorl are suitable for planting.

b).Planting in the Field
Prior to planting the polybag plant, a part of the filled soil of the planting hole should be removed, and the polybag plant should be brought to the planting hole and the base of the polybag should be removed. Then, the plant should be lowered into the planting hole carefully positioning the graft union a 2 inches below the ground level. If the graft union is not hardened ( If it is green in colour), the graft union should not be filled with soil. The remaining 2 inches of the hole should be allowed to settle naturally. Since the green graft union may be rotten when the water collected in the hole, a small drain should be made to take the water collected in the hole away.

Intercropping/Mixed Cropping

If it is envisaged to grow an intercrop or a mixed crop with rubber, the spacing of planting crops is 2.5 x 7.75m and the intercrops or mixed crops should be planted leaving a gap of 8 feet for rubber. If Tea is grown as a mixed crop with rubber, two spacing systems have been introduced. The first spacing is 2.4 x 12m. Accordingly, 7 rows of tea may be interplanted between 2 rubber rows. The second spacing is 2.4 x 18m. Accordingly, 12 rows of tea may be interplantd betwen 2 rubber rows.
The due period- (May - June),(October - November).
Crops suitable for intercropping at the immature phase of rubber are Banana, Pineapple, Passion fruit, Sugarcane, Annual and Seasonal crops, Medicinal Plants.
Crops that can be grown without compromising on the rubber density in unit land area – Coffee, Cocoa
Crops that can be grown changing the rubber density in unit land area – Tea, Cinnamon, Pepper.
Crops suitable for intercropping at the mature phase of rubber are Cardamom, vanilla, Rattan, Anthuriam.

In addition, Poultry farming and Apiculture on rubber lands are other potential sources for income generation.

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