11/13/2012 - By Harrell's

When I pose this question to growers the answers that are most often given is the program should be reliable, it should be foolproof, and most importantly it should be cost effective. Let’s look at each of these factors…

1. Programs should be reliable

Well this seems simple enough, after all, the whole reason why pesticides are applied is to keep unwanted pests off of valuable crops, right? Composing a sound IPM program starts by knowing the crops you produce, as well as the pests that make these crops their home. Knowing your crop includes tracking its history from the propagation stage to when it is placed on the ground at your operation.

All too often I’m called out for a variety of pests on plants that have just been brought in from an outside source... an avoidable and usually expensive headache. I recommend quarantining incoming plants stock for at least 30 days for monitoring and scouting before placing in with the production stock. Also ask the seller what pesticides they have applied in the last 30-45 days - that way you can integrate the new plants into your current IPM program much easier. This also helps to ensure that there are no overlapping products, thereby avoiding any unforeseen phyto problems.

Knowing your crops also means knowing the potential pests that can infect them, and good growers with sound IPM programs know how to anticipate these small problems before they become BIG problems. When dealing with diseases, whether fungal or bacterial it is easiest to use a preventative approach. Once the disease is established in a crop it is almost always there to stay unless dramatic and costly measures are taken.

Know which crops get what diseases during certain times of the year and start applying fungicides BEFORE the disease appears. Most insect species are easily controlled with this preventative approach too. Systemic insecticides are one of the safest and most effective ways of applying insecticides in this day and age. Some pests like mites can only be controlled once the insect is present, so reliable IPM programs utilize thorough scouting.  Reliable IPM programs target specific diseases and insects on specific crops at the critical times of the growing season to extinguish pests before populations build.

Sound spray programs are also built off of years of records and experience. Records that indicate a wet cool spring means trouble for crops susceptible to Downy mildews and bacterial diseases. They indicate that when the first day of the year the thermometer hits 85 F they should start anticipating Powdery mildew on susceptible species. They take cues from Mother Nature and they don’t try to fight it!

2. Programs should be foolproof

So what does it mean to be foolproof? I mean all spray programs have holes in them right? Well not necessarily... I have found that most sound spray programs are actually two programs that are used side by side. The first program is the broad spectrum/catch all approach, or as Marshall calls it, the shotgun approach. Now this approach usually conjures up thoughts of pesticide slurries that contain 4 or 5 products, sometimes even more. But with foolproof programs, growers use one or two wisely selected products to protect their crops. Think of it as leaving the 12 gauge on the shelf and using the equally as efficient 20 gauge... both can do the job, but one is much more powerful and potentially damaging.

Older spray mixes like T-methyl + Subdue still go the distance when used sparingly and cover a very wide range of diseases. Newer products like Pageant and Orvego offer two modes of activity in one package which makes them easy to use and cost effective. Sound spray programs will often utilize systemic insecticides in these mixes to avoid making multiple costly applications. Always perform a jar compatibility test when using new product mixtures!

Once a pest establishes itself in a production crop, and a broad spectrum approach isn’t working anymore, a sound spray program will then begin to utilize more specialized products. Most labeled fungicides only control a handful of diseases, so using them on a large scale can be wasteful and costly. These pesticides should be reserved for when specific pests appear. Once a crop becomes infected with a disease or insect that specific problem should be targeted until acceptable control is achieved.

3. Programs should be cost effective

The last section is a good segue into this section. By utilizing the dual program approach I believe that programs can be built to be very reliable and at the same time save the grower money. Wide spectrum products and tank mixes that catch many pests give growers the most bang for their buck. They control many pest species and are usually very cost effective per 100 gallons. Specialized pesticides are usually a little more expensive and control fewer labeled pests, so reserving these for specific tasks can not only save growers money but also help to prevent against fungicide resistance problems, thereby making them foolproof and reliable. 

For more information or for help designing or modifying your IPM programs please contact your Harrells Tech Services Representative.