North American Fruit Explorers mailing list at ibiblio

[Road's End Farm <organic87@frontiernet.net>]

Hi Dennis,

I downloaded the actual study, which was linked to in the link you sent. I don't grow apples, so I'm not the best person to comment on this (again, I'd suggest you contact people actually growing organic apples in your state; if I remember a previous discussion on this correctly I found several by googling); but I did notice the following:

First of all, this is not actually a comparison of an organically maintained orchard to a conventionally maintained orchard. The entire orchard was conventionally maintained in the use of fertilizers and herbicides. A number of trees within the block were then, for one year only, given a partially organic spray program as far as insecticides and thinning were concerned (even some of the "organic" insecticide sprays were substances not approved for organic production), while other trees within the same orchard were conventionally sprayed with insecticides and thinners.

Organic growers spent years arguing with Cornell about such "trials" in their vegetable plots. 
Cornell finally agreed, and set up a separate organically managed farm. (I don't know whether they have any apples there or not.) The setup used in the study you quoted is the proper setup for experiments involving single-item variables; but organic management is not a single-item variable, it's a whole-field technique, and not just because organic growers are being nitpicky. Much of organic pest management is provided by naturally occurring beneficial organisms. The field as a whole needs to be hospitable to beneficials, and it can take several years for the populations to build up. Beneficials can be affected by soil conditions as well as by the presence or absence of sprays applied above ground in the general area, and so may be affected by growing techniques that do not involve obvious insecticides. Attractiveness of fruit to pests can also be affected by fertilization and other growing techniques.

Another couple of points, less major than the above, but they did occur to me:

-- The size difference in organic fruit was attributed by the study to the use of a thinning spray. I don't know how many organic growers actually use this spray to thin. This would have affected the yield results. (They also may have used too much of it, as they say the organic thinning spray reduced the number of fruit per tree to fewer than the number on the conventionally thinned trees.)

-- I don't know how many organic apple growers actually use this many sprays overall. Because something is listed as permissible doesn't mean that all growers are using it. (Of course, I also don't know whether most conventional apple growers actually use this many sprays, either.) If growers who do have high levels of beneficial insects in practice use fewer sprays, this would affect their cost comparisons. (I bring this up because my experience with vegetable crops is that most organic growers use far less in the way of insecticides than someone looking at a list of possible-use materials might conclude; and because I have seen comparisons of cost or environmental impact which assumed that it was common for organic growers to use repeated applications of materials that in fact many didn't use at all, and most of those who did used less often. Again, I don't do apples, and don't know how the situation compares.)

-- There were clearly varietal differences in results, though I couldn't figure out from the study to what extent this affected the overall results, as varietal differences, as near as I could tell, were given for organic and conventional treatments combined, rather than separately. Choosing the right varieties for the specific farm is an important part of organic technique. There are certainly varieties that can't be successfully grown organically, in any given climate; a fair answer to the question of whether apples can be grown organically in the Northeast, and if so at what cost, would require specifying what varietes were being discussed.

As I understand it, apples are one of the hardest crops to grow organically in this area. However, I don't think this particular study actually proves much of anything on the subject.

--Rivka
Finger Lakes NY; zone 5 mostly


On Apr 9, 2008, at 6:46 PM, <dmnorton@royaloakfarmorchard.com> wrote:

> <x-tad-smaller>Here is a excerpt from the latest Scaffolds IPM newsletter from Cornell that I though everyone might find interesting:</x-tad-smaller>
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> "In summary, pesticides plus application costs totaled $650/A for the standard program as compared with $1,173/A for the organic program. Total yield per acre (including fruit damaged by pests) was 209, 409, and 861 bushels per acre for the unsprayed, organic, and standard treatments, respectively. Pest control costs per bushel were $2.98 for fruit from the organic block compared with $0.76 for the standard. Results from this trial show that pest-free apples can be produced organically in New York, but organic producers will likely need at least a 400% sales premium compared with standard growers, due to the high costs and reduced yields associated with organic pest control. Further research may lead to cost reductions and improved productivity for organic systems, but farmers currently considering a switch to organic apple production should verify that their prospective buyers will be willing to pay a signifi cant premium for organic fruit."
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> <x-tad-smaller>To read the complete article go to  </x-tad-smaller><x-tad-smaller>http://www.nysaes.cornell.edu/ent/scaffolds/2008/080331.html</x-tad-smaller><x-tad-smaller> </x-tad-smaller>
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