Insect & Disease Control Strategies

This is an excerpt from the Book called “The Backyard Orchardist ” by Stella Otto . Continue reading to learn more about Insect & Disease Control Strategies, thanks to the author.

Insect & Disease Control Strategies

In the recent past, most gardeners had then impression that insect and disease control for fruit trees could only be accomplished by spraying some sort of chemical on a regular basis. With new developments in integrated pest management and increasing awareness of organic gardening, less chemical intensive options are now available. Which methods are, at first glance, the easiest and quickest for the novice gardener. Organic gardening and integrated pest management take more time, knowledge, and observation, but are becoming increasingly preferred by many gardeners for their environmental benefits. Since there are many names and terms associated with current pest control philosophies, let’s first define the ones to be used in this chapter.

Biological Or Organic Control

With present day ecological awareness, organic pest control is much talked about. Just what exactly is organic gardening? Justifiably, there is some confusion since individuals and various groups each have their own definitions. As someone are defined their understanding to me, “unsprayed and unfertilized,” is a very simplistic definition. On the other end of the spectrum are organic grower groups that do allow selective use of certain approved pesticide in their certification programs. For purpose of this book, organic strategies will be defined as those that use primarily naturally occurring materials are good or safe and that man-made ones are all bad or dangerous. Excessive manure applications can cause just as much water pollution as manufactured fertilizers. Some organic pesticides, such as nicotine sulfate, are more poisonous than manufactured ones, such as the synthetic pyrethriods.

Growing fruit organically requires that you have a very thorough understanding of all the parts of an interrelated cycle: the growth processes of the tree, the fruit, the pests and diseases, the beneficial insects and microbes; and how they each influence each other. The major advantage of an organic system is that it works primarily in harmony with the natural ecosystem. Disadvantages are that it can be very labor intensive and fruit may not be as picture perfect and blemish free as many people have become used to. Crop loss can sometimes be extensive. Research so far has shown that tree fruit are one of the most difficult crops to grow under a strict organic regimen. Several pests, most notably brown marmorated stink bug and curculio, are extremely difficult to control with currently available organic options. Consequently, a large percentage of crop loss to insect damage is something you may have to accept when growing tree fruit organically.

In 1997, the Organic Material Review Institute (OMRI) a private, nonprofit organization was established to determines whether or not a product qualifies as organic under the USDA’s National Organic Program. Products are reviewed against the organic standards. Those that comply are listed on the OMRI Brand Name Products List and can bear the OMRI logo. If you choose to use strictly organic products, it may be helpful to look for this logo.

Synthetic Or Chemical Control

Pest control with synthetically-produced chemicals used to be the mainstream method. This approach assumed that all “bugs” and diseases are problems to be eliminated. In this book, chemical materials are considered to be those manufactured or extensively processed as opposes to those left in their fairly natural form or derived from primarily naturally occurring sources. Advantages of chemical use include quick, effective control of insects and diseases with a minimal expenditure of labor. A calendar spray program, where pesticides are applied on a 7 to 14 day schedule, is often used when broad spectrum synthetic pesticides are being relied upon for primary control. This can be a practical approach for first time home orchardists, while they experience the learning curve of the more knowledge-intensive organic or Integrated Pest Management systems.

Chemical controls are largely responsible for the attractive abundance of unblemished, affordable produce found on our grocery shelves. Undesirable consequences of this method include insects and disease developing resistance to certain chemicals as well as ecological ramifications, such as ground water pollution. Accidental poisoning of the person applying chemicals and possible long-term health problems are also risks of chemical control systems when they are not used judiciously.

Integrated Pest Management

Integrated Pest Management (IPM for short is a viable alternative for today’s fruit growers. In many ways, it is a middle ground between strictly organic control methods and chemical control. Integrated pest management encourages you to take the advantages of both chemical and organic methods, weigh them against the respective disadvantages, and apply them in the context of an interdependent system. Like the organic philosophy, IPM is most effective when you have a thorough understanding of the plant, the pests, the beneficial insects, and the ecosystem. Practiced properly, IPM encourages you to quantify and keep a history of your plant’s problems, and its performance. This sounds complicated and like a lot of effort, but if often allows you to eliminate unnecessary work and use only minimal synthetic inputs.

As far as pest control, it will lead you to a better understanding of the natural balance between crop damage and the need for insect and disease control as well as the interrelatedness of pest insects and the beneficial insects that keep them naturally in check. An integrated pest management system gives you a framework within which you decide what trade-offs you are willing to make:

To limit the amount or type of pesticides you use, you may be willing to accept more blemished fruit and a few worms or invest more time and labor in sanitation.
Perhaps you would rather use a less toxic synthetic pesticide than a highly toxic “natural” one.
Employing cultural practices, such as use of disease resistant varieties offers additional options for reduced pesticide use.

The choices are yours when you have sufficient information. Most of the pest control strategies discussed in this book have an IPM focus. If your personal philosophy leans heavily toward either organic or synthetic methods, by all means, follow your chosen path. Consider though, that IPM may offer you the best of both worlds.

Effective Pest Control

One of the main concepts behind both the integrated pest management approach and the organic gardening approach is that not every occurrence of a fruit tree pest or disease demands instant control. Some pests can be tolerated and some diseases prevented by use of alternative cultural practices. If, however, pest or disease conditions become severe, some type of control method often becomes necessary. All effective control programs share certain basic principles. They include:
Planning for problem prevention
Proper identification of the pest or disease
Selection of an effective control strategy_ whether that be a predator insect, biological pesticide, or chemical material
Proper timing in application of the control method to target the pest or disease at its most vulnerable stage
Complete coverage of plant tissue when sprays are used
Evaluation of results to analyze how future outcomes could possibly be improved

Problem Prevention: First and foremost, you would do well to take a proactive approach to disease prevention. Growing disease resistant varieties is one big step in the right direction. However, resistance to one disease does not automatically mean complete immunity. Nor does it mean that the variety is resistant to all diseases. In most cases, some preventive protection is still in order. When measures are taken to protect newly emerging plant tissue from disease spores early in the growing season, it is very possible to short circuit the disease cycle or at least greatly reduce reproduction of spores that will lead to ever-increasing disease pressure. Early control can greatly reduce the need for additional sprays later in the season. It is well worth it to learn the cycles of disease development to stay ahead of the game.

Proper Identification: For many home gardeners, a small amount of fruit damage is acceptable. That fruit can often be used for jam and jelly, cider making, or other home preserved products. If your crop is being damaged and you have come to a point where you feel control is needed, your next step will be to properly identify the pest or disease. The two preceding chapters should be able to help you recognize the most common problems. Your local extension agent can often help identify more unusual localized problems.

Selecting An Effective Control: Once you have identified your pest, you will need to choose your control method from various options: cultural, mechanical, or chemical. Mechanical removal or a cultural practice may work for your situation. Alternately, you might choose some type of predator insect or microorganism. In some cases, control may involve some type of pesticide. Pesticide (-cide meaning “to kill”) is the term generally used to define a material that kills pests_ be it an insect, disease, or weed. These materials can generally be broken down into the categories of insecticide (to kill an insect), fungicide (to kill fungi responsible for many disease), bactericide (to kill bacteria), or herbicide (to kill weeds or “herbs”).

Choosing a strategy targeted specifically for the purpose of controlling your given problem is preferred in integrated pest management. A target specific material is often the most effective means of control and, if chosen properly, it will not be injurious to other desired insects that also inhabit your garden. Careful use of a selective pesticide can even be a valuable tool in letting beneficial insects gain control of a runaway pest population and bring it back into an ecologically balanced control situation.

Proper Timing: One key aspect of a successful pest or disease control program is applying the selected material at a time when it will be most effective. The importance of proper timing cannot be overstated! Even the most well chosen material will not work well if it is applied at the wrong time. You are already aware from that most insects are likely to be vulnerable to control when they are immature or unprotected. Diseases are usually easiest to control before the bacterial or fungal spores have colonized plant tissue or increased to great numbers. This may often be early in the season when plant tissue is just emerging and before disease symptoms are visible on the plant.

Since each growing season is different, it is impossible to say that a given spray applied on a given date will always work. General recommendations, correlated to the tree growth phases can be more reliable. As you keep records and gain experience, you will be able to fine-tune your timing. Keeping track of pest emergence, plant development, and growing degree days over time will offer you even more accurate predictions for timing insect and disease control methods. Pest emergence tends to correlate quite reliably with certain plant growth stages, while disease development is highly influenced by weather conditions and temperature. The charts show the critical control periods for the more common insect pests and diseases in the northern United States. In the South, the sequence will still be the same, but may occur several weeks earlier. Use them as a guide.