I’ve been fighting bac. spot for over a decade on my home orchard. I’ve found I don’t need to spray to harvest at the house, but do need to spray once per week. I’ve found about 5 weekly sprays starting at about shuck split is enough to give pretty good protection. I see maybe a few spots on the fruit, but it’s not bad. If I spray the full 8 or 9 labeled sprays, then the fruit will be completely spotless.
This is the first year I’ve used Mycoshield at the farm, and I didn’t get near the response as I do at the house. I just have too much wind there and too many susc. varieties, which allow the spread of too much innoculum. As Ray suggested in another thread, if you have good recommendations for your area from a good university, that will generally give the best results for success.
You mentioned J.H. Hale as producing very clean fruit. I’ve read that J.H. Hale is very susc. to bac. spot, so my guess is that your J.H. Hale is either mislabeled, or perhaps you are looking at scab instead of bac. spot. That said, you probably are dealing with bac. spot, and that your J.H Hale is really something else. I’ve generally found that if a peach is reported to be susc. to bac. spot, it shows up for me.
I’ve not found that bac. spot mainly affects younger trees, which Ray speaks of in his locale. Here, once I see bac. spot, it’s pretty much there every year, unless I spray. I do agree to keep the trees open. Not only does it promote drying, but also there is less bac. spot to wash down on the lower foliage if a lot of that dense foliage is removed. Many times I see more bac. spot on the foliage which is lower down because of poor drying, less sunlight to kill the bacteria, and more innoculum wash down.
Thanks for this discussion as I didn’t know that oxytetracycline was available to me.
I was reading that the bacteria overwinter in buds, and cracks in bark. So you certainly don’t want to ever miss dormant sprays. Even though not totally effective. Every reference suggests dormant sprays should be done.
I was thinking about how I controlled bacteria, and one is salt, which for sure is out. Another is hydrogen peroxide. I can’t think of a better substance to penetrate any crevice in any tree. I guess though if the bacteria are spore forming, the spores may stand up to it. Live bacteria should die.on contact. We depend on our surgeons to keep a sterile field by washing with an iodine product, such as betadine. I’m not sure why it isn’t used in AG applications? Before antibiotics we used sulfur products, so I use copper, and also a lime sulfur treatment. Not at the same time. Usually lime in the fall, copper in the spring. Sometimes homeowners with limited professional resources has to Macgyver through a problem!
I just “bragged” about my J.H. Hale’s resistance to Bacterial Spot when I posted a photo of my tree in the what’s happening today thread, so now I feel bad and may go change that. Either scenario you mention is entirely possible- my tree may be another mislabel and I could be misidentifying what I have, but as you said, I’m pretty sure its BS.
I’ve been sort of a defender of big-box store fruit trees, though I know many people here say its not worth the convenience, cost savings, time savings to first fruit, etc. But I need to amend my position slightly. If I go through my 100 or so trees and compare those I bought from reputable on-line nurseries vs big box stores OTHER THAN LOWES, I’ve actually had fewer mislabeled trees from the BB stores. But when I include Lowes, its a WHOLE other story. Honest to goodness, no exaggeration, a MAJORITY (meaning well more than 1/2!) of my Lowes Trees have been mislabeled. I really need to calculate the percentage of Lowes mislabels- it will be a shocking percentage. I don’t know if this is the fault of Lowes or their supplier (which in my area is 100% Berry Family Nursery according to tags), but Lowes trees are mislabeled more than half the time. That’s just crazy!
Mark,
You’re right about BS affecting mainly the lower branches that get
very little sunlight. Those branches and the fruit on them don’t get the
chance to dry as quickly as the other branches do. The innoculum is
spread by the spores splashing to other branches and fruit, when it
rains. That’s why it’s so important to keep the tree as open as possible
and to prune out those lower susceptible branches.
The problem with this kind of mixture is that it may be treating more than one needs. The pyrethroid use, if done in excess, will bite your butt sooner or later, and even a couple sprays can send your beneficial insects to the graveyard and create mite, scale and other outbreaks.
I’ve switched to pyrethroids at many sites and I’m having much more problems with these pests than in the past- and with only 2 sprays.
I lost all of my peaches to the freeze this year, otherwise I would be fighting BS like everyone else due to the very wet season.
I agree that an antibiotic like Mycoshield will be required to help with the Bacterial Spot in many cover sprays. It should be easy to mix at around 150PPM. Unfortunately, it has has a 3 week PHI so its probably too late to spray.
Copper may help, but the helpfulness of copper depends on the MCE. The higher the MCE, the more metallic copper and hence the better it works to kill the bacteria. Copper can be safely applied before the tree leafs out in a large dosage. After the tree has leafed out, just a small about of copper in terms of ounces of MCE per acre can defoliate the tree. The link below describes how copper works and list the proper dosage for different types of copper. I was very surprised to see that just a few ounces PER ACRE of Kocide 3000 is suggested as a safe amount for BS control in a cover spray. For comparison, the dormant rate for the same material is about 2 # MCE/acre or over 5 POUNDS of Kocide 3000 per acre during the dormant period
I didn’t read the whole presentation Blueberry, but I’ve read before that if copper is used on peach to control bac. spot during the growing season then expect some defoliation from the copper. The copper protects the fruit, but even at low dosage actually causes some foliar damage.
I’ve used copper soap well into summer without foliage burn on apricots and tomatoes. For apricots it is to help control B. spot and was recommended by my distributor’s advisor for that purpose. .
Cueva is the name of the product I use but it costs over $100 and comes in a 2.5 gallon jug. There is a Bonide product, as I recall that is packaged for small properties. Just google copper soap or ask Drew.
Thank you Alan I’m sure you already stated the name and I’m sure I missed it so thank you for giving the name again. The large quantity wouldn’t bother me as I run a pretty big operation and sometimes need large volumes of product. As long as it has decent storage life it would work. I’ll look into both products.
It certainly is useful for tomatoes based on my own experience. Until I started using it I depended on chlorothalonil, and I don’t really like using that stuff once the tomatoes are forming. Call me superstitious.
I use it for peach leaf curl and it is adequately effective, but Kocide is probably more economical for this purpose. Apparently the dosage is relatively high for copper in this form- about a half cup a gallon, as I recall.
I don’t either. I use copper. I have been light on the sprays this year because it was dry, that was a mistake! I’m seeing septoria coming on, on most of my plants. No big deal, they will produce a decent amount before dead.
Hi Ahmad. My news for 2017 is awful, but honestly I think my big problem was brown rot more than bacterial spot. I had trees completely full of fruit that I ended up not getting a single peach from-talk about heart breaking! I thinned them just right, sprayed for imidan for bugs, but having never had brown rot before I didn’t spray anything else. Those peaches grew and looked almost perfect until just days before they were to ripen- which makes it hurt that much more. Just as they were almost ripe enough to pick, they would start to get a hairy fungus that would start in one area and completely spread across the fruit within just a day or two. IT was just awful.
THis year, I sprayed copper and Captan in dormancy, captan just before bloom, and will start using myclobutinyl after bloom. Don’t use that formula or schedule…it has more to do with what I had on hand that what might be perfect. But the point is I’m working on brown rot this year so hopefully I won’t have a repeat!