North American Fruit Explorers mailing list at ibiblio

[Don Yellman <don.yellman@webformation.com>]

1.  I have been using Orbit for late brown rot on peaches since 1992, when I noticed 
ads for it in a little magazine I subscribed to at the time, called "American 
Fruit Grower".   In the ads, Orbit was recommended for use on peaches, and I 
special ordered a quart through the local Southern States Co-op.  That quart cost me 
$120, which at the time I thought was outrageous.  It was not, and I still have most of 
it and use it nearly every year.

2.  The insert accompanying the chemical purchased in 1992 specified use only on "certain diseases in pecans".   Now I find, to my surprise, that the labeling has expanded geometrically, to include all stone fruits, a wide range of tree nuts, and even berries.  Active ingredient has remained exactly the same: Propicanazole at 41.8%.  When I first started using Orbit, I felt a little guilty even using it on peaches, which I need not have been.  I was using it off-label, but now, 16 years later, almost nothing is off label for this chemical.  So much for labels.  Buy a new iron and you will find a label warning that "this product becomes hot in use".  

3.  Aware that Orbit is a systemic, and conscious of the danger of developing 
resistance, I have used it sparingly over the years.  Like many product 
labels, the Orbit label devotes most of its text to warnings and spurious 
advice, with mixing directions in ounces per acre.  But I did the best 
calculation I could based on the recommended 4 oz. per acre in 50 gallons 
water for tree crops, and, using an eyedropper, add 1 1/2 to 2 cc's per 
gallon to my 4-gallon SP-2 sprayer.  If Orbit is now being sold under a 
different name on the wider consumer market, it is quite likely to be lower 
in active ingredient (this was the case with Imidan when it was still widely 
sold).  Mixing should follow instructions of the re-labeled product.  I would 
expect it to be expensive.

4.  I apply Orbit only twice; once just as peaches begin to color up, and 
again much closer to harvest.  I will feel much better about this knowing the 
new label permits use right up to harvest.  I also plan to expand its use to 
plums and apricots, in accordance with the new labeling.  I have not used 
Orbit every year, but I see brown rot when I don't use it and none when I do. 
 Previous experiences applying Captan (also pretty pricey stuff) were 
uniformly negative, with no control I could notice.  I also dormant spray 
stone fruits twice with Kocide, which I believe is helpful against diseases 
of the tree itself, but no help on late brown rot of fruit.  I have never had 
problems with blossom blight or earlier stone fruit diseases, possibly due to 
the dormant sprays.

5.  If you are an organic grower, Orbit may not be of interest.  I tend 
toward the organic, and follow many organic practices which may be called, in 
modern parlance, integrated pest management.  But IPM will not stop brown rot 
in the humid climate of the mid-Atlantic.  I have never tried Immunox (Nova), 
Indar, or other systemics, and am mistrustful of organic fungicides like 
Serenade.  If Pristine is primarily marketed as organic, I would have doubts 
about that as well.

6.  I am still cautious using systemics on the fruit trees, but comforted by 
the fact I use only tiny amounts of Orbit in the spray mix, when compared 
with the volume and frequency of application of other fungicides.  I realize 
this comparison may be inadequate for some.  But we are still walking around 
here after 15 years of eating peaches treated with Orbit, and I have seen 
nothing in the press or elsewhere indicating health problems  caused by this 
fungicide.  Commercial growers have been using it for longer than I have.   I 
wish we had better, documented studies from independent and unbiased sources 
testing fruits for residues that may cause health problems.

Don Yellman, Great Falls, VA