Most of our practises are aimed at increasing biodiversity. We hope to achieve greater biodiversity at many levels by
- incorparating animals (eventually geese,chooks, pigs, bees etc) into the system.
- increasing the range of fruit crops grown.
- increasing the varieties of apples and peaches grown.
- establishing belts and borders of native vegetation to encourage more diversity of insects, birds, etc.
- trying to increase microbiological diversity in the soil and on the plants themselves.
We believe greater biodiversity will help us create a more balanced
eco-system, less suceptible to the agronomic risks associated with monocultures and help us spread our financial risks.
1. Pests and Benificials
Codling Moth and Light Brown Apple Moth are controlled by "mating disruption". This involves placing dispensers in the tops of trees that saturate the air with the scent of the female moths, making it difficult for the males to locate the females.
Light Brown Apple Moth is a native insect. The large number of predatory wasps that occur in the native bush prevent a build up of large numbers of Light Brown Apple Moths in bushland. Monocultures such as vineyards and orchards support few predatory wasps and commonly see huge numbers of Light Brown Apple Moth. We plan to plant belts of native vegetation through out the orchard next winter.
codling moth
light brown apple moth & grub
Heliothis and looper caterpillars attack fruitlets in November and December. The hole visible below the looper in the photo wil appear as a raised wart on the mature fruit. They are controlled by spraying Bacillus thuringiensis (Bt). This is a bacteria that infects the digestive system of caterpillars.
looper on fruitlets
Lady bird are present in large numbers on the young peaches(Nov 08). We suspected they were feeding on aphids but couldn't actually see any. Perhaps they had already cleaned most of them up?
ladybird on young peach leaf
Woolly aphid are present in extremely low numbers, because they are predated on by the tiny parasitic wasp Aphelinus mali.
parasitic wasp
Garden snails have not been a problem in our orchard since converting to organic practices. Control measures are no longer necessary. Previously they caused significant damage to blossom in October.
snail on apple tree
Weevils likewise have not been a problem in our orchard since converting to organic practices. Control measures are no longer necessary.Previously they would build up to damaging levels, eating the skin of the small apples in November and December.
weevil
Birds. Crows have been the main bird problem at our orchard at Kalangadoo. We use an electronic bird scarer which makes a variety of pre-recorded bird sounds - with reasonable success.
In 2007 we had a huge flock of musk lorikeets at the orchard we lease near Mt Gambier. They ate about 16 tonnes in week or two. However in 2008 only a small number of both musk lorikeets and crimson rosellas were present. We are quite happy to share a small percentage with the birds and in fact deliberately leave a few apples on the top branches for the birds.
musk lorikeets finishing off the Pink Lady June '07
and definetely not interested in sharing with us!
Black Spot can be an absolutely devastating disease for apple growers, and its control is particularly challenging for organic apple growers. While the use of copper hydroxide, wettable sulphur and lime sulphur are permitted under organic certification standards, we have been looking at alternatives.
We had been trialling compost tea for blackspot control. This was a total disaster two years running with 100% damage on those rows sprayed.
This season we sprayed the trees (when dormant) with a brew of "non-composted " leaves and twigs from our old house orchard which has never had any form of fungicide applied (yet never gets bad Black Spot). The logic was that we were after leaf dwelling microbes which could potentially out-compete the Black Spot. We wonder if the process of "composting" favours ground dwelling organisms - hence we are using leaf litter that has not been composted. We are expecting it may take some years to achieve a high level of control but have risked half the Kalangadoo Orchard.
So we may have quite a few seconds for a year or two, but we are quite excited by the project. Our aim is to eventually do away with all foliar sprays and just fertilise through the soil.
The tree line is mulched to a width of one metre with wheat straw every year. Any weeds coming through the mulch are hand weeded. While mulching is time consuming, there are considerable benefits - conserving water, increasing biological activity in the soil, increasing the ratio of fungi to bacteria in the soil (very desirable for tree crops such as apples) and reducing soil temperature in summer.
For the first few years the mulch did a good job of controlling weeds. However as time has gone on, the straw breaks down more and more rapidly which is probably good for the soil but not so good for weed control. So we are currently trialling strip grazing some geese to control weeds.
They can do a terrific job of weeding.
The management issues are:
1. the need to have a high stocking rate and move them frequently. We manage this with movable electonet fencing. www.allsun.com.au This works but is time consuming.
2. The geese are vulnerable to foxes when sitting on nests. In addition to the fence we have a Maremma dog which is very protective of the geese. The draw back is that he loves eating the eggs!
3. You may have heard that geese just eat grass but we can assure you that they eat apples too. Even when they are grass green and only as big as your thumb nail! So from about November until harvest we have to get them out of the orchard. We are also changing the tree training in some blocks so there are no apples within a metre of the ground so the geese can remain in these areas all year round.
Twelve years ago when the first of our apple trees were planted, a dry bank was chosen and the ground was mounded to ensure the trees were not water logged. We believed we were so lucky to have unlimited ground water ! We also believed with careful management and mulching we could probably grow most varieties with out irrigation! No longer!
During the last two years we have lost signifigant amounts of fruit due to lack of rain and our bore drying up. We have had to deepen the bore from 13m to 44m and convert from under tree sprinklers to drippers (half this year and half next year -finances permitting!). Just when we need the ground water we are struggling to find it.
Sad to see no water in the swamps again last spring and certainly less frogs about.
Looking after the soil is paramount. While the necessary nutrients may be present in the soil, it is the presence of microbes which frequently makes them available to the plant.
The ground water flows through a limestone aquifer so the water is high in calcium. It is therefore unneccessary to apply calcium sprays as is done routinely in most other apple growing districts around the world. The trees tend to be vigorous and nitrogen is also present in the ground water, so we tend to avoid fertilisers containing nitrogen.
The trace elements copper, zinc and manganese are of more concern. Regular foliar sprays of fish emulsion/seaweed extract, and post harvest foliar sprays of trace elements are applied. Last Autumn we also applied Sea Minerals solution to the soil. It contains all the minerals found in the sea but with the sodium chloride removed.
Rock phosphate is applied to the soil as required.
We are tending to move away from foliar sprays in favour of ground applications.
We train our trees into a low, narrow hedgerow just over 2 metres high. This gives excellent light penetration and keeps labour costs down.
Some trees are supported by a trellis, depending on tree vigour/rootstock.
7. Pollination
We have a great diversity of insects in the orchard so have found it is not necessary to introduce bees.
8. Thinning
All thinning is done by hand. We had been trying to remove 90% of the flowers with scissors in October and after that we hand thin the small fruit. (Conventional growers thin flowers and small fruit with chemicals). The difficulty is that if we don't finish thinning within 4-6 weeks of flowering, we don't have fruit on the trees the following year. To some extent we are trying to overcome this problem by heavy pruning in winter.
Right now, December, we are thinning apples. We like about one hand span between each apple. If they are closer than this they tend not to be as large or quite as intense flavour, and the trees certainly won't have as many flowers next year. If there are not enough apples the trees grow too vigorously and we have to do lots of pruning the following winter and the fruit tends to be too big and watery.
We are currently leasing Riquiers orchard at OB Flat near Mt Gambier. The crop from both orchards should be fully certified as organic in 2009
The Riquier Block at OB Flat with the Pink Lady in full bloom
The crop looks fantastic at this stage, although we did suffer some hail damage in November. There was damage on the west side of the trees at both orchards, which we are stil trying to thin off.
The stone fruit planted last year are growing well as you can see at left. We hope to have peaches for sale at the farm gate lateDecember 2009
Young peach tree at Kalangadoo 27.11.2008
Some interesting old varieties of apples were budded on to dwarfing rootstocks last February. Varieties include
Akane
Elstar
Cox’s Orange Pippin
Ribston Pippin
Jonathan
Christmas apple
In winter we cut back the rootsock, took the budding tape off and the new little trees are growing nicely as you can see in the picture.
This section of the orchard will have no fungicides applied at all.
