Help - Brown Rot intervention?

Katie,

I wanted to offer an answer to your question. Copper has little effect on brown rot.

Here is an efficacy chart for brown rot fungicides. It’s for plums, but the same pathogen affects peaches (M. Fructicola). You’ll notice on the chart, copper gets a very low rating (i.e. minimal and often ineffective).

http://ipm.ucanr.edu/PMG/r611902111.html

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Thank you for your response. This will be my first year doing any kind of spray schedule. I did have brown rot on cherries last year. I believed the marketing on the copper bottle. I appreciate real world experience that is offered here.

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That is a great list, thank you. It’s so frustrating to find a highly efficient fungicide for home orchards that doesn’t cost an arm and a leg. I use Topsin + Captan in Spring and then switch to Tebustar (cost only $35) in Summer. I had zero rot so far here in zone 7b Maryland. The problem with Tebustar is that they slapped it with a 5 day REI, but 0 day PHI. Still looking for an alternative.

You have a killer set of fungicides in your regime. It’s going to be hard to find a more cost efficient solution than you already have and probably no better results.

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Most of the group 3 fungicides are reasonably effective. Indar is generally recognized as one of the best for brown rot, but it is somewhat expensive on a gallon basis. Bumper/Tilt/propiconazole is a very cheap alternative with a 24 hr REI and a 0 PHI, probably equivalent to tebuconazole for brown rot control.

Topsin has become irrelevant for scab and brown rot control in most cases, because of resistance.

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Thank you, @Olpea and @jaypeedee! I think I’ll try Bumper once I’m out of tebuconazole.

A bunch of us here went in on buying some, and I have replaced Infuse with Indar. So I use Indar and Prestine in alternate sprays.

AKA Infuse. I see it works well for the blight too! I will have to go back to this once I run out of Indar.

I wish I could just use Infuse, I really do, but unfortunately I have too much heat/ humidity/ rain in my area so I need something a little bit stronger. @Drew51, your pluot pictures are absolutely gorgeous. I’m just getting my 4 in one pluots set for the first time this year, I’m hoping they will be almost as pretty as yours.

Well yeah why I went to Indar, I don’t need it really. I have low brown rot pressure. Still I don’t want it in my orchard, ever, at all. So using Plant Guard (Prestine) and Indar or Infuse has worked great for me.

Cool, good luck with it! I just took a photo of my Indian Free tree for a couple reasons. To show how one can graft and control height. The tree is 8 years old and five feet tall.
It has three major scaffold over 6 secondary scaffolds. I grafted 2 nectarines to it, and 3 pluots, giving me 6 cultivars on a 5 foot tree. Each cultivar has a scaffold or secondary scaffold dedicated to it. Easy to manage at this height too.
I also wanted to show how here bloom time is compressed. Right now all my trees have flowers. Peach, plum, and cherry. This does not happen in other locations.

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I can’t tell from your profile if you are a commercial grower or a backyard grower but unless laws have changed the REI does not apply to members of the farm family only workers covered by Worker Protection. Regardless of the exact laws, I still abide by the REI for my own protection. Captan is another fungicide with a higher REI than PHI. In the case of Captan, I believe the REI is due to possible eye damage especially when thinning fruit.

Indar is my go to fungicide during preharvest too.

I’ve wondered about systemics and how safe they are to use with fruit bearing plants.Will much be absorbed into what we eat?bb

Like most folks I rely and comply with the labels.

I try to exceed the PHI by a factor of at least 2X or more just to be safer.

It may not be possible to be 100% certain about the safety, but we now know that some early farm chemicals like Lead Arsenate or DDT were more dangerous then expected.

Don’t believe “organic” chemicals are automatically safer than synthetic chemicals and I would not use any if I could grow sell-able fruit without them.

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Honestly, I’m not sure if anyone has done a study of home orchards vs the very rigorous commercial spraying. I try to spray the smallest amount I can get away with, and if it’s dry I don’t spray unless I see a problem. But big orchards can’t get away with selling ugly fruit.

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Even a small commercial orchard like mine can’t sell ugly fruit! We promoted our ugly but low chemical apples hard for several years but our customers refused to buy. Fortunately, the pigs really liked them even with a few blemishes.

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Yeah, it’s true. I noticed that orchards close to me are using the words Integrated pest management lately and people seem to mind less. I’m a chef, and most of the time the pickiest people in a restaurant don’t know how to cook!

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So I will ask all of you that have been gracious enough to make some suggestions. I am learning - mostly that you need to spray if you want the bulk of your fruit rather than give it to the bugs and fungi. I looked at Scott’s low impact stuff - and will follow some of those recommendations. I was a bit lost seeing Olpea talk about the half-life of Captan and acidifying my water. How does that factor in using a hose end sprayer with a reservoir for the concentrate? What are thoughts on using one for concentrate sprays? I understand I won’t be able to do this with Surround, but some of the products mentioned here could - but should they? BTW - I have 2 sprays in - The Fruit Tree and Plant Guard and the Fruit Tree spray (Captan) - I am still not in bloom.

Hose end sprayers are not designed for fruit tree spraying, you will need to purchase a pump sprayer. I expect it is hard to get enough concentrated spray on the tree without wasting tons of chemical - hose end sprayers put out way more water than you want.

@DMend, I had pretty good luck with propiconazole in Maryland, but now I use Indar (alternating with something else, currently Elevate) and the results are even better.

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Thanks @scottfsmith. How is your experience using propiconazole on Euro plums? That’s the only reason why I never tried it, I have a few prune and gage plums and the label said it’s not to be used on them. I’m pretty happy with tebuconazole, it’s excellent, just not happy with the REI.

I don’t think my label had anything like that. The only issue I heard of is Stanley can be smaller size if propiconazole is applied during bloom. I am not spraying during bloom and I don’t have Stanley. And, I never noticed anything. So, I think it is fine to use but if you spray during bloom I would not use it then on Euros.

BTW on the topic of early brown rot, my white apricots are getting lots of shoot blight this spring. I usually do an Indar after shuck split but this year I waited to spray anything as there was no curc activity and I didn’t think diseases would do much given how cold it was. A mistake in retrospect.

That’s good news. I don’t spray during bloom, so I’ll be good. I only have Wenatchee Moorpark apricot, which I heard it’s not the best tasting. It also got shoot blight. It’s been raining a lot here, I’m not surprised.