I have a home orchard with a few apple trees, one of which is a 12 year old Honeycrisp. I had to harvest the remaining fruit today (Tuesday low of 22 F) and decided to sort and count the apples for codling moth damage - results below.
My codling moth treatment strategy is pretty basic: spinosad every 9-10 days according to our local university extension spray date calendar for my area. They consider this an organic treatment relative to other sprays. Sample Spray Table Sample IPM Pest Advisories
(The other things I have to worry about fire blight and powdery mildew.)
Total apples: 114 No Damage: 63% (72) Surface Sting: 22% (25) - I could eat this fresh from my hand or it would store well. Minimal Damage: 8% (9) - I could cut out the small damaged section before eating with a paring knife or I would prioritize eating it first from storage. Extensive Damage: 7% (8) - A large portion is rotten and I would have to cut it out with a cutting board or eat in a couple days with no long-term storage.
A local friend who has an orchard also said dormant oil is another organic alternative to use, which I might try in addition or alternating sprays next year.
Caveats:
I was picking the remaining fruit - some damaged fruit fell off or I picked it already and I disposed of it, but I also picked some nice apples already too so maybe it evens out. So these aren’t exact, but the results are promising, at least this year.
It might rain once a month on average from June to August, so the sprays don’t get rinsed off often, BUT I’ve been told the sun’s UV can also degrade sprays so maybe that’s a wash.
For many years I did nothing and have had high codling moth pressure in the past. I started this consistently two years ago.
I didn’t assess other damage from birds, stem cracking, etc.
It’s hard to spray consistently for 3 months - you get busy or leave town and have to work around that…I always tell people organic apples are the hardest fruit to grow organically relative to others I have (cherries, plums and apricots being the easiest).
I’m eating or giving away everything so I don’t need 100% efficacy like if I was selling - 100+ great apples from a tree is plenty.
I agree that fruit trees are much harder than other food. I used to plant butternut squash seeds in May and in July or August I had a crop and a big one at that. I am talking around 10 squash. I then started growing fruit and have had minimal fruit the last few years. I know it will increase over time but it is certainly a wait. I also have to spray cherry and peach tree I have.
I had a very significant reduction in Codling moth damage by simply putting an Electronic Insect Killer near my apple trees (no spray at all). It’s on a dusk to dawn power switch.
Spray Imidan right before the fruit is large enough to attract coddling moth, it’s very effective. By the time the fruit ripens a couple months later the pesticide has broken down from sun and weather, leaving little to no residue.
Not strictly organic, but the resulting fruit is pretty close to pesticide-free. Something to think about, if you’re just concerned about residue and not the definition of “organic”.
The Electronic Insect Killer Stan suggested sounded so interesting, I’m taking the gamble.It comes with a mosquito lure …but replacing that with a Coddling Moth lure might just work. I used CM lures with traps this year.
Didn’t have much damage this year, compared to other years, but hard to know if it was due to the traps. Once the insects were stuck to the yellow cards, it was hard for me to ID!
I know if that Coddling moths are active a few hours before and after sunset. The electronic device might work. At least the zapping sound will be satisfactory reinforcement.
Probably 2" across, although apple varieties vary in size. When they’re really hard and bitter green the moths don’t sting, so before they become slightly edible. One spray at the right time can often be enough, although I’m sure commercial orchards do more than a single spray.
I looked up the product and I’m considering it, but wanted to ask about the “cartridges” they would have you replace every thirty days. What are they, where do you get them, how pricey are they, that sort of thing.
Although codling moth development is more or less synchronized, not all moths will be at the same stage on the same day. For this reason the expectation is that all sprays will be reapplied at least once (except in situations where only very light control is required) to catch not only the earlier developing moths but the later developing moths, as well. The minimum interval before reapplication is listed among the instructions for using each compound and varies according to the kind of spray used but is usually around ten days.
Timing is everything. Non-organic growers do their best to apply the minimum amount of chemicals. They try to maximize the effectiveness of those they do apply by applying them at the right time. Fortunately for growers (unfortunately for codling moths), there are strategies for determining the optimal time.
First flight typically is detected with pheromone traps, which are available commercially and are within the means of the backyard gardener. Traps are put out before full bloom and are checked weekly. Biofix is set at the end of the second week when at least five moths are captured after the first week that any moths are captured (Rothwell). On the next warm evening when sunset temperature is greater than 62°F, the cumulative Growing Degree-Days is the “biofix,” and codling moth developmental stages are predicted by offsets to cumulative Growing Degree-Days from that point.
Those cartridges contain attractant/lure for mosquitoes. You don’t need these when using the zapper against CM. You can probably get better results if using the zapper with a specific CM lure (to be purchased separately), but I didn’t use any lure and it still was quite effective judging by the lack of damaged apples.
