Selection of Site
Chestnuts prefer sloping, well drained, deep soil at an altitude of between 200 and 1000 metres above sea level. While acidic soils are reasonably well tolerated, the preferred range is from pH 5.5-6.0. Shallow or heavy soils with impermeable, clay subsoils are unsatisfactory. Soils must have excellent drainage. Recently cleared land is best avoided to help resist the root rot, Armillaria mellia.

Climate
Climate is an important factor to be considered. Chestnuts have been found to produce a better crop when they are subjected to chilling during the dormant period - frosts and snowfalls are beneficial rather than harmful to chestnut trees. Bud-burst is later than most other fruit trees so late frosts can be damaging to young buds. Chestnuts require full sunlight, so shaded or southern facing positions are best avoided.

Preparation
Ideally, one should be planning at least one year ahead. This will allow ample time to order the chosen varieties from the nursery and deep rip the proposed lines of planting.

The ground should be cleared and levelled as much as possible to make it easier for mowing grass, harvesting etc. later.

Spacing
The layout or spacing of the grove will depend on many factors. Current plantings range from 7m x 7m to 20m x 20m, with the closer plantings being more popular. Factors to be considered are the slope of the land and the type of tree - some spread laterally, others tend to grow tall. Where chestnut trees touch there is virtually no nut production. Finally, if you are considering a close planting regime, consider your attitude to `heavy pruning' or even `tree removal' before you proceed.

Planting
Most trees are two years old when sold. At this age the root system is quite extensive. Removal from the nursery bed (sometimes done with a backhoe) will often damage the root system as well as reducing it's size. Trees are usually sold barerooted with the roots covered with damp sawdust or straw or wrapped in hessian. It is important to maintain a satisfactory level of moisture to the roots until planting. Immediately prior to planting, the root system should be carefuly examined and damaged roots removed or trimmed with secateurs.

Trees should be well watered in after planting (use at least 10 litres of water) and planted at the same depth as they were planted in the nursery. The top should be reduced by about one-third to one-half to compensate for the reduction in the root system. Some growers advocate painting the butt of the tree with white paint to protect the bark from sunburn. Sunburn can be a major problem until sufficient canopy has formed to provide protection.

Varieties
Early plantings of chestnuts were seedlings. Naturally many of these trees produced inferior quality nuts. Gradually trees, which produced more acceptable nuts, were selected and propagated as named varieties. In most instances nuts from the desired variety were used to produce rootstock onto which scion wood was then grafted. With the emergence of Phomopsis and Phytophthora, attention has been directed towards the development of disease-resistant rootstock. This research is in its infancy in Australia but quite well developed in France.

The varietal evaluation committee of the Chestnut Growers of Australia Ltd is currently assessing existing varieties of chestnuts available in Australia. Whilst early results may suggest certain varieties have the desired characteristics, it is too soon to be able to reliably recommend which varieties should be propagated. Many factors affect the quality and characteristics of chestnuts (eg climate, soil conditions, pollinators).

Previously favoured varieties such as Early Marone, Lucente and Sword are now going out of favour.

The ideal chestnut falls freely from the burr, has an appealing look, good taste, a single embryo, a thin pellicle which does not intrude into the nut, peels easily, is free of Phomopsis, and stores well.

Some varieties will do better in certain areas than others. Select the appropriate variety for your area by talking with local growers and by thoroughly researching your local area. For instance, the variety Buffalo Queen usually performs very poorly south of the Great Dividing Range.

For the grower who is extremely well organised and forward thinking, consideration should be given to obtaining a supply of nuts of a preferred rootstock and planting two or three nuts in the chosen position. The best plant at each site can then be selected for grafting to the desired variety in situ. In this way you avoid the possibility of major trauma to the root system which may occur when removing a tree from the nursery.

With the fresh nut market currently well supplied, those embarking on new plantings would be well advised to look into varieties for both the fresh produce and the processing market. Presently, chestnuts are sold under the generic name ‘chestnuts’. In the future, it will be necessary to define the variety of the chestnut before going to market.

Early, mid and late varieties of chestnuts.

Irrigation
This is a much-debated topic of chestnut production. The preferred rainfall for chestnuts is 800mm+ per annum. Chestnuts prefer water all through the growing period with even distribution throughout the year. Irrigation will achieve an even watering throughout the year. If rainfall is below 700mm per annum it may be wise to install an irrigation system. Drip systems are considered better. When installing the system, bear in mind the tree should be watered in the outer half of the circle formed by the drip line i.e. keep the direct stream of water away from the trunk. Mulching in one of the many forms available will help, particularly during the hotter months. Irrespective of annual rainfall, it is advisable to water young trees at least during summer and early autumn.

Diseases
The three major diseases affecting chestnuts are Bubbly Bark, Phytophthora and Phomopsis.

Bubbly Bark is currently caused by an unknown pathogen, and can kill a large percentage of new trees (<5yrs) and severely stress older trees.  More information on bubbly bark is available from the education and training section.

Phytophthora is a root rot caused by Phytophthora cinnamoni which results in the death of the tree.

Research has been conducted into the treatment of this disease with phosphorous acid by trunk injection and foliar spray. Encouraging results have been obtained.

Phytophthora occurs most commonly in soils which are poorly drained and have a clay subsoil. Prevention of Phytophthora by careful site selection is strongly recommended. Research is being conducted into the identification of Phytophthora and Phomopsis resistant varieties. The former is well advanced in France and this information could be available in Australia shortly.

Phomopsis is a fungal disease of the kernel of the nut, due to Phomopsis castanea, and is a serious problem in the market place. It is not easily detected and usually does not cause great harm to the tree until present for many years. Affected nuts may only be detected when the tree is about eight years old.

Another cause of root rot is Armillaria mellea. This is frequently seen where native trees have recently been removed from the site of the grove. All stumps of such trees should be burnt. Ideally pasture should be sown for three years prior to planting the chestnut trees.

Fortunately Australia is free of Chestnut Blight (Endothia parasitica), the disease which almost completely wiped out American chestnuts. The Japanese and Chinese varieties appear to be resistant to Chestnut Blight. Our quarantine service is aware of the danger of Chestnut Blight to chestnut trees and its lethal affect on many varieties of Eucalypts.

If major problems exist with tree health, soil and leaf analysis should be carried out. Crop Health Services Diagnostics at the Institute for Horticultural Development (IHD), Knoxfield (Tel: 03 9210 9222) provide a range of commercial plant-pest services These services are also provided by other private commercial companies.

Pollination
There is very little documentation of the pollination requirements of chestnut trees. Whilst all varieties produce male catkins and female flowers on new season's shoots, the male pollen may no longer be present when the female flower is ready for pollination. It is therefore recommended that several different varieties be planted for the purposes of commercial production. Unfortunately, there is no reliable information as to which varieties are the best pollinators for other varieties.

Pollen is transferred from one tree to another by wind. Several growers have introduced bee hives to their groves but have not observed any significant benefit from them.

Where large numbers of trees are planted, a mixture of varieties is recommended eg. two rows of one, then two of another variety. Where large blocks of a single variety have been planted it has been noted the trees in the middle of the block do not produce as well as those on the edges.

Pruning
Pruning is not required as fruit is produced on the current year's growth. However, there is growing evidence that some varieties such as Purton's Pride, Lucenti and Noxurli may benefit from pruning which is designed to increase the nut size. 'Pruning Chestnuts for increased Productivity' - a report on the Dr Araki presentation by Peter Hall will provide further information.

In the first few years the tree should be trained to a central leader. When well established (three-four years old) it is wise to prune so branching will commence about two metres from the ground. This will allow access under the canopy for machinery such as tractors. Severe early pruning may predispose the tree to suckering.

As the trees progress dead wood, crossing branches and those with a very narrow crotch are best removed. It is better to keep the canopy open rather than cluttered as chestnuts have high sunlight requirements.

Branches which do not extend to the edge of the canopy should be removed as nuts are produced on the outside of the tree.

General Care
Weed control is necessary to prevent competition of grasses with the young tree, particularly in the early years after planting. This can be achieved by careful use of herbicides or cultivation. When trees are well established mow regularly to just beyond the drip-line. This leaves a suitable surface from which to harvest the crop.

The instructions on the label must be followed carefully when using chemicals.

Pests
Rabbits and wallabies can severely damage young trees. Some form of guard against these is strongly recommended, for example wire netting, sisalisation. Deer and kangaroos also cause some problems.

The sulphur crested cockatoo is prone to carry out "beak maintenance" on young trees, damaging branches up to 10 mm in diameter. At harvest time rosellas can be troublesome.

Cattle and horses can also cause damage to fallen chestnuts and young trees. Temporary fencing may be required when the trees are young and when the nuts are falling.

Harvesting
Harvesting is done once the nuts have fallen from the tree. Depending on the variety, and to a certain extent the season, most nuts fall free from the burr. Again depending on variety, most nuts drop from mid March to early May.

Nuts are mainly gathered by hand. Where nuts fall in the burr, even loosely, strong protective gloves (e.g. nitryl-dipped cotton or leather gloves) should be used. The spines on slightly dry burrs are fiendish.

Large suction harvesters are available. They require a tractor for power, are costly (about $30,000) and in many instances are only marginally quicker than hand harvesting. Some growers are trialing a modified version of the machines used for picking up golf balls. As yet, the ideal harvester has not been developed and hand-harvesting is still the most suitable.

As chestnuts have a high water content they behave like a fresh fruit and rapidly dehydrate if left on the ground. Consequently, it is recommended nuts be harvested as soon after falling as possible, preferably within 24 hours and then transferred to cool storage (at 0°C). More detailed information on post-harvest handling is contained in the technical Chestnut Quality Manual developed by Mr Dan Ridley, Department of Natural Resources and Environment.

Grading
The Chestnut Growers of Australia Ltd has developed a size grading system which is based on the size of the hole through which nuts will pass. Whilst there are some problems with this system, it is widely accepted in the market place.

The most commonly used graders are slowly rotating cylinders, the walls of which are made of sheets of perforated metal, the holes in each sheet getting progressively larger as the nuts pass along from one segment of the grader to the next. One problem which can arise with this type of grader occurs when too many are fed into the grader too quickly. As a result of this, nuts may be four or more deep as they pass over the first set of holes, leading to nuts being carried past the correct set of holes.

Nut Sizes
The recommended grade sizes are:

In response to requests from overseas customers some growers have used a 36mm hole instead of 38mm and added a section with a 40mm hole. Whilst this move to seven grades has been accepted by some Australian wholesale agents others regard it as a nuisance. It is suggested you discuss this matter with your wholesale agent.

Yield
Due to the many factors affecting the annual yield of a chestnut tree it is not prudent to give figures which one could use to predict the financial returns from establishing a chestnut plantation.

In general terms, it is fairly safe to assume a 10 year old tree will produce 10kg of nuts (there are examples of 10 year old trees that have produced 100kg of nuts - these are exceptions!).

A recent study suggests it takes 13 years to reach the break-even point in establishing a chestnut grove.

Packaging
The majority of fresh chestnuts are sold through the wholesale markets. Most customers prefer chestnuts to be consigned in 5 kg boxes (10 kg packages - boxes and hessian bags - are also used). Growers are advised to discuss packaging with their wholesale agent or client if selling direct.

Prices received vary across the chestnut season. Early falling nuts (March-April) normally bring a higher price than the later falling nuts. Nut size is a significant factor - larger nuts attract a higher price. Variety has only very recently had a slight influence on price. It is expected this will have a big influence in the future.

In recent years, the price paid for large nuts has ranged from $8 to $12 per kilogram in the early part of the season (March/April) adjusting to $5 or less as the season progresses