What You Will Learn…
- Understand the types of pests and diseases and why they are attracted in your plants.
- How will you deal with these pests and diseases using ecological methods without using chemicals
- Develop climate change resilience by increasing soil carbon
- Interpret a soil laboratory test
- Make quality compost and worm castings
- Use plant diversity to improve soil fertility
- Plan a comprehensive soil fertility program for your land
In this course you learn what influences pest, disease and weed outbreaks, how to prevent them, and what to do if prevention fails. Pesticides, in the broad sense including insecticides, fungicides, herbicides, miticides and nematicides, are no answer. In fact they make the problem worse by killing off the natural controllers and changing the chemical structure of plants that ends up making them less able to resist attack. Plants have an immune system that is easily interfered with, just as it is for humans with a toxic load and poor nutrition.
The emphasis is on creating diversity that attracts the beneficial insects, and on providing plants with the best nutrition. Sometimes we are not able to give the plants all they need; in the last resort there is a multitude of environmentally safe plant extracts and other substances that can help with the problem, at least in the short term.
You will learn that weeds fulfil an ecological role. They colonise bare and degraded soil. The best way of preventing weed infestations is to rehabilitate and refertilise soil and never leave the soil uncovered. As with pests and diseases, though, there will be an interim when other methods will be necessary to reduce competition with what we want to grow.
The final message here is that pests, diseases and weeds are not to be feared. It is degraded soil, lack of biodiversity and lack of ground cover that are to be the focus of attention.
In the natural environment, plants, pests and predators are kept in balance. Farmers need to develop systems that mimic this feature. This means biodiversity. Nature never creates a 1,000 hectare field of wheat or canola or maize, or even 2 hectares. Therefore monoculture is inevitably unstable. Farmers can plan for particular aspects of biodiversity – this is a major strategy for plant protection.
The second strategy is to provide the plant with its best possible immune system, which means fertile balanced soil, adequate moisture and no toxic inputs.
The third strategy is control without harming the natural predators. This can be done with deterrents, traps, timing, the careful use of minimal impact biocides, and the release of particular predator or parasitic insects or insect diseases.
In this course, we will focus on some of the common pests and diseases that conventional farmers are facing and how can we make our plants recilient.
Who is this course is for:
For all farmers and anyone who wants to grow plants without using chemicals.
Farmers have had to deal with pests, diseases and weeds ever since agriculture commenced, using a range of management techniques. While some of these techniques included chemicals, the modern era of large-scale pesticide use is only 70 years old. Agriculture had been carried out for 10,000-15,000 years before that.
Despite the massive amounts of chemicals in use, damage caused by pest, disease and weed infestation has not diminished. The chemical era has at the same time caused immense damage to health and the environment and expense to farmers. Only the chemical companies have benefited. Pesticides have been extraordinarily profitable for the manufacturers but not for the farmers. They are no answer.
This lesson looks at history, the effects of pesticide use, and the factors in pest, disease and weed attack.The example of glyphosate, the best-selling of all pesticides, a herbicide that the manufacturers claim is perfectly safe, is used to illustrate the myth of pesticide safety. If glyphosate is safe, then all the others are deadly poisons. The issue of genetic modification is also dealt with, as GM has largely been developed for pest control purposes. GM is also a failure.
- Topic 1: Pests and diseases in perspective
- Topic 2: History of plant protection
- Topic 3: The costs of pesticide use
- Topic 4: What attracts pests and diseases?
In natural ecosystems pests and diseases rarely break out. They are there, but so are those organisms that feed on them. Plants tolerate some damage. When plants are grown outside a natural ecosystem, damage is more acute. Farmers can moderate that damage by creating habitats for the natural controllers, by creating an effective self-regulating farm ecosystem.
- Topic 1: Predators and parasites
- Topic 2: Creating diversity
There are two ways in which diversity may be useful: by providing habitat and food for predators, and by restricting the diet and spread of pests and diseases. For biodiversity to work, it requires a good understanding of the numerous relationships between plants, plant eaters and natural enemies. This of course varies with different climates, locations, environments and management systems, so what applies in one region may not in another.
Monoculture provides unlimited food with no barrier to prevent a rapid population explosion of pests. Apart from ecological considerations, polyculture can lead to a reduction in financial risk and, in self-sufficiency situations, a more varied diet. It can provide barriers to the spread of pests and diseases, camouflage for crops, and habitats for predators and parasites. Excess nitrogen produced by legumes can be utilised by other crops.
Genetic diversity of crops is some sort of insurance policy – if a disease attacks it may not attack all varieties of a crop. For pests and diseases which spread slowly, like Phytophthora, two-spotted mite and codling moth, it is of great advantage not to have large areas of the one sort of plant together.
It takes time for a balanced farm ecosystem and perfect soil fertility to be developed, and it might not be the complete answer to pest and disease outbreaks. This topic offers a large range of benign pest and disease suppression options to supplement the role of natural predators, all of which are acceptable under organic standards. They include physical, biological, botanical and chemical controls. Some recipes are provided.
- Topic 1: Traps, barriers, plant breeding, hygiene
- Topic 2: Biological control, pheromones
- Topic 3: Organically acceptable biocides
In this lesson we look at methods of managing a selection of individual pests and diseases. Those chosen for discussion are widespread, but some are specific to temperate regions and others specific to the tropics. Even if they are not relevant for a particular region, the options may be applicable to pests or diseases that are not covered here.
- Topic 1: Concrete examples of pest management
- Topic 2: Concrete examples of disease management
Weeds are plants growing where you don’t want them to grow. Rather than something to fear, weeds can be a good indicator of soil conditions, and can perform many useful roles. Farmers need the ability to judge when weeds exceed their beneficial role and become an impediment to crop production.
- Topic 1: Conditions that favour weeds
- Topic 2: Problems and uses of weeds
- Topic 3: Developing a weed management strategy.
As there are few organically acceptable herbicides for weed management, farmers have to rely on management systems. There are many different implements that can be used without causing too much soil disturbance. Mulching and cover crops have multiple benefits apart from weed suppression. Animals have a big role to play in weed management as they used to prior to the largescale availability of chemical herbicides fifty years ago.
- Topic 1: Weeding implements, solarisation
- Topic 2: Weed avoidance strategies
- Topic 3: Using animals
- Topic 4: Biological control, organic herbicides
Topic 5: Concrete examples of weed management
Author, Biological Agriculture Researcher
& Organic Farming Teacher. From a small Merino farm in NE Victoria. B.Arts (Monash 1971), Cert. Horticulture (Burnley 1975), Graduate Diploma Sustainable Agriculture (Orange 1998). Involved with Organic Agriculture Association (Gippsland) since 1985, currently vice-president. Nursery work. Small organic producer (certified by NASAA for 5 years). Wrote and taught Diploma of Organic Farming 2001-2016 (NMIT, Federation Training).