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michael357

Topsin M and the U of KY

Michael
10 years ago

I was reading through the U of KY's orchard spray program for homeowners and came across something interesting at the bottom, the recommendation of using thiophanate methyl (Topsin M / 3336 F) for disease control on fruit trees. Having examined labels for Topsin M and 3336 F, it is obvious that neither are to be used on trees from which the fruit will be consumed. Am I missing something? A link to the site is below.

Here is a link that might be useful: U of KY home spray program

Comments (11)

  • alan haigh
    10 years ago

    Topsin M does come in packaging with labeling that advises for its use on apples, pears and stonefruits and is highly recommended by Cornell for summer fungal diseases such as flyspeck, sooty blotch and various fruit rots. This is for producing commercial orchards.

    Not all packaging of any given ag chemical has the same labeling.

  • Michael
    Original Author
    10 years ago

    One of Cleary's 3336 F labels states, " do not use on home orchards / fruit trees after fruit set" and is listed for rusts (puccinia) brown rot (monilinia) and a host of other disease causing M.O.s of course. To me, this implies it can be used by the homeowner for those diseases on fruit trees prior to fruit set though no particular fruit trees are mentioned on the label. I'm still not certain if it's ok.

    In searching through the web looking at some other of Cleary's 3336 F labels, that line about home orchards was not included, can't remember, not sure about that, just certain about the one printed out in front of me now.

  • alan haigh
    10 years ago

    On a commercial label there are restrictions on the number of applications in a seasons or quantity per acre. Perhaps Clearys is being cautious about potential misuse.

  • Michael
    Original Author
    10 years ago

    I'm just baffled about the ambiguity of uses under the heading, Horticultural Applications." There is one line that gives me pause for Venturia scabs, "don't use fruit on crabapple and pear for food purposes". Makes me wonder why the U of KY has Thiophanate Methyl listed in their home orchard spray program, granted it is referencing Topsin-M and not 3336F. After further review, I see that the Topsin-M label clearly states to use it only on non-bearing fruit trees, guess it would be for nursery stock. I am aware that Clearys likely didn't want to go through the process of getting 3336 labeled for fruit trees, instead heading for ornamentals and turf.

    Under turf apps. there is a lot of specificity.

    Every container of the commercial stuff is very specific as to the disease, rate, crop and timing. I'm sticking with "not on bearing trees", period,but, am still mystified about the 3336F label's comment on home orchards not after fruit set. The U of KY sure has Topsin-M after fruit set, seems off label to me to be using it on bearing trees to start with.

  • alan haigh
    10 years ago

    It is used for bearing apple trees and has been for decades. If you want to know Cleary's reasoning, contact them. U. KY didn't specifically recommend Cleary's., did they?

  • olpea
    10 years ago

    " I see that the Topsin-M label clearly states to use it only on non-bearing fruit trees"

    Michael,

    If you look at the label a bit more closely, you will see Topsin-M is labeled for bearing fruit trees. I suspect the part you read was, "Use on all labeled non-bearing tree fruit, tree nuts, and grapes"

    If you read "use" as a verb as in, "I use my pickup every day", then it makes it sound like Topsin M can only be used on non-bearing trees.

    However if you read "use" as a noun as in, "Use of my pocket knife as a pruning tool leads to frustration" then the label is simply explaining how to use Topsin M on non-bearing trees, not stating they can only be used on non-bearing trees.

    Either way if you scroll down you will see the label directions for using it on bearing fruit trees. For example, it is labeled for peaches for brown rot, blossom blight, and scab. It has a 1 day PHI.

  • Michael
    Original Author
    10 years ago

    Thanks Olpea, I obviously wasn't paying enough attention in all of those English classes or maybe I'm just suffering from label fatigue:) My Technical Writing prof. would certainly not approve of the wording on the label either. Maybe I'll look one more time with rested eyes.
    Upon further review I see 2 things on the Topsin M label - just after, "Use on all labeled non-bearing tree fruit" it states, ".....during the non-bearing years of new plantings and nursery stock". After that, the crops are listed. To me it still is stating for non-bearing trees only as no exceptions are explicitly stated. So, what's up KY? Hope to get in touch with them and find out without making an arse of myself.

  • olpea
    10 years ago

    Michael,

    I'm certain Topsin M (from United Phosporous) is approved for bearing pomes and prunus, else why would the label mention pre-harvest use on apples and pears, along with directions for treating fruit brown rot on stone fruits, as well as PHI restrictions. None of that would be necessary if it was approved only for non-bearing orchards.

    Although it isn't used as much any more because of resistance issues, Topsin M has been used a long time to protect fruits from scab and rot.

  • alan haigh
    10 years ago

    In NY it still seems popular and useful to commercial growers for the control of flyspeck,sooty blotch and rots (and so much cheaper than Pristine). I bet it still works fine for all the labeled pests for home orchards not located near commercial fruit production. They use up formulas like toilet paper.

    I may buy some this season for a couple sites with clients that covet pristine apples.

  • olpea
    10 years ago

    "I may buy some this season for a couple sites with clients that covet pristine apples."

    If you try it on any stone fruits, let me know how it works for you. I've been reluctant to try it because everything I've read says there is widespread resistance from scab and rot.

    Apparently the single mode of action is easily overcome by M.
    fructicola and scab, but still effective for summer apple diseases.

  • alan haigh
    10 years ago

    I'll let you know, but I will probably be rotating materials.