Spray amounts guide

It sounds like that Bonide spray is the Triazicide Once and Done bug stuff mixed with the commercial grower’s Pristine product. I think you have a good idea alternating “Pristine” with MFF. In lists I have seen of effectiveness for brown rot, e.g. http://www.ipm.ucdavis.edu/PMG/r5100111.html, Indar is #1, MFF (propiconazole) is #2 and Pristine is #3. I don’t want the pyrethroid so the Bonide spray is not good for me and the only way to get Pristine is in commercial quantity.

Re your copper dose, you are close with that but hard to say beyond that. Kocide 3000 requires less than other coppers I used previously (Champion and Kocide 2000) so I would probably up it to 2Tbsp per gallon - Kocide is more efficient per pound than other coppers.

I agree copper is best avoided, I only use it when I have a serious disease issue needing attention. Apples I phased out copper when fireblight got to be not so bad. Peaches I am currently down to once a year from twice a year, and I may try phasing that out as well.

Actara (Thiamethoxam) gets 5 stars against PC, RAA and 4 stars against BMSB

Assail gets 3 stars against PC, 5 stars against RAA and 2 stars against BMSB

Imidan gets 4 stars against PC, 1 star against RAA and 2 stars against BMSB

Asana gets 3 stars against PC, 5 stars against RAA and 2 stars against BMSB

Actara is described as a second generation neonic, but I don’t see the chemical available in any consumer grade insecticide

Charts only take you so far. Asana works better in cool weather so in areas where it is hotter during PC’s season it would be less effective. Charts like this also fail to take into account persistence. As an example, I’ve seen charts that rated Sevin as being as effective as Imidan, even though it loses efficacy much sooner.

I don’t know if Assail is as effective as Asana or even vice-versa but Asana seems like the best choice in residential areas when you are spraying many orchards that pets and even children may be wandering in shortly after spray (dogs don’t read signs and owners are careless).

This is when I really miss Olpea’s presence here- he always had a handle on the current research in great detail. He warned me of the limitations of Assail in controlling PC and steered me to appropriate research.

I just spent 30 minutes trying to find that and came up with almost nothing- just one chart from a southern U. that had the same evaluation as yours. I was surprised at how much higher a rating Avaunt got- a 5 to Assail’s and Asana’s 3. I would have expected a 4.

I did find research that suggests Assail is much safer for bees than Actara- especially honey bees.

Hopefully some of the newer, less toxic insecticides will be available in a consumer grade product soon.

I have not used Avaunt before. It is listed as mode 22A which I’m not familiar with. Great on PC, but does not touch BMSB

I’m still confused by the fact that many insecticides with a Caution signal word have such a long PHI, where more toxic insecticides often have shorter PHI. Also, many of the newer chemicals start with an A, so its just about impossible to keep them straight! Actara, Altacor, Asana, Assail, Avaunt, Ambush, Apollo

Yes, Avaunt is pretty useless against all manner of plant bugs. Here, amongst my worst stonefruit pests, are tarnished plant bugs and green stink bugs. Both Asana and Assail seem to work reasonably well on them. At least I don’t have to worry too much about mite outbreaks on peaches and J. plums compared to apples (and E. plums) when using Asana.

Scott, I added Captain Jack’s Deadbug Concentrate to the insecticides. I noticed too that Entrust is available as a liquid as well as a wettable powder.

Hi Re: Imadon on Plums for PC
On the advice of Al Cosnow, senior MidFEx member, I have been using Imadon (1 TBSP/gal) after petal fall on plums, with one application two weeks later. Sometimes, I do a third application two weeks after that, and that’s it. This is for the very nasty plum cucurlio. Hundreds and hundreds of plums !! Been doing this for four years and never looked back.


Where are you located Patrick?

I’d love to get down to that level of spraying but I’m too paranoid here in the buggy and humid mid-Atlantic (Northern Virginia)

Prospect Heights 60070.
zone 5.
the curcs supposedly have only one reproductive cycle around here

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Are there suggested amounts that show the amounts to be used per gallon for Topsin and Avaunt? Also is it possible to update your guide to show the shelf life of product? A deciding factor for backyard growers is the shelf life of a product - example I do not mind paying $140 for Avaunt if will last 5 to 10 years on the shelf. $140 divided by 5 = $44 a year. That is affordable vs $140 for one year (If it looses effectiveness after 1 year). Thanks - Spud.

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Usually the shelf life of dry chemicals is longer than liquid formulations but you are right to wonder about the specifics, as they vary a great deal. The way I’ve found out in the past is to contact the manufacturers of any given substance. Usually loss of efficacy is apparently a gradual process and can sometimes be countered by upping the dose, even though this would be technically illegal. If the company gave a ball park of gradual weakening of product it would certainly be justifiable to fudge the law rather than disposing of the unused pesticide.

It is, unfortunately, illegal to take chemicals out of original packaging, because the best solution would be for home growers to split large purchases of materials. Once again, the law is not sensible because one could put material in equally secure packaging with a printed label of the product taken from your computer with no reduction in safety.


Hi Alan - Understood about the small quantities and splitting them. In this case I am looking at buying Topsin and Avaunt in full quantity but spraying them them in small qty thus the need for the per gallon rate. I understand Avaunt to be less toxic than Imidan. Thanks - Spud.

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My unofficial calculation is that 1 TBS should be sufficient to make 5 gallons.

Its going to take some math and basic assumptions to arrive at a suitable rate for Avaunt in a small sprayer

The rate for apples is 5oz/acre. I spray 100 Gal/acre on apples which would convert to 5oz/100 or to only .05 Oz per gallon! I’m not quit sure how to get an accurate measurement for such a small amount of material. 28 grams to an ounce, so I guess you could convert it to grams which would be 1.4 grams if my math is right. Most inexpensive ($20) digital kitchen scales will do grams.

EDIT: Lots of $20 scales will measure as low as .01 OZ so the metric conversion is not required.


Can someone check my math and logic -

Imidan is sold in 5 lbs packages. 16 ounces in a lbs, 2 tbsp in an ounce.

16 x 5 x 2 = 160 gallons of spray per 5 lbs package. For some reason I expected the amount of spray from a 5 lbs package to be much higher. When I read the label (this a cut and paste) -


(East of the


Japanese Beetle, Oriental Fruit Moth, Peach
Twig Borer, Plum Curculio, Rose Chafer, San
Jose Scale, Spotted Wing Drosophila


2 1/8 - 4 1/4
(1.5 – 3 lbs ai)
(or 3/4 -1 lb per
100 gals not to
exceed 4 1/4 lbs
product or 3 lbs ai
per acre)

After reading the label and the application rate is 3/4 to 1 lb per 100 gals I would expect to get a minimum of 500 gallons of spray from 5 lbs of Imidan. Where did I go wrong on my logic?

In my spray notes I have Imidan at 3 3/4 tbsp. per oz. Don’t recall exactly where I got that info.

Edit to add:

Found this pdf that lists imidan at 2.43 grams per tsp. https://www.uky.edu/Ag/Horticulture/masabni/Publications/HO-83.pdf

So three tsp in a tbsp would convert to 7.29 grams per tbsp… Divided into 28 grams per oz comes out to 3.84 tbsp. per oz

Hi J.D.,

I looked at the UKY document from your link. They show the rate for Imidan being-

Imidan 70WP 1.3 lb, 2.5 TSP/Gal. They note that this is the low end of application.

According to Google 1 pound = 96 teaspoon [US] . 96/2.5 = 38.4 Gallon of spray per pound. 38.4 * 5 = 192 gallons of spray.

So 192 gallons (weaker dose) vs 160 gallons (strong dose) seems plausible.

I must not understand correctly what the label means when they say -

3/4 to 1 lb per 100 gals

Again that implies 500 gallons of spray from a 5 lbs package. I am missing something.

They list Imidan at 2.43 grams per tsp. There is roughly 454 grams in a pound.

454 / 2.43 = 187 tsp per pound. 187/2.5 = 74.8 gallons of spray per pound. 74.8 * 5 = 374 gallons of spray.

Not sure why Google is telling you 1 pound = 96 tsp. Its a weight to volume conversion, every material can have a different density thus a different variable.


J.D. is correct that different materials have different densities. It can be confusing, but keep in mind for practical purposes a pound is strictly a weight measurement. Teaspoons and tablespoons are really volume measurements. However it turns out, when measuring water, a tablespoon of water weighs half an ounce. So tablespoons and teaspoons can also correspond with weight (if you know the density of the product you are measuring out).

It’s sort of like a bushel. In the strictest sense, it’s a volume measurement. But because everyone wanted more precision, than a bushel offers, our government (USDA) defined weights for bushels of various crops. So a bushel of apples is defined as weighing 40 lbs., bushel of peaches 50 lbs., bushel of corn 56 lbs., etc.

Obviously Imidan is more “fluffy” than water, thus weighs less per teaspoon/tablespoon.

For Imidan, at 4 lbs. per acre rate, a 5 lb. package would make about 310 gallons of spray solution, based on a full dilute spray of 250 gal./acre (I’m using rough numbers here, because per gallon numbers aren’t that exact anyway.)

That would mean an ounce would treat about 3.75 gal. of water. (Remember and ounce is not two tablespoons in this case.)

I use a gun powder scale to weigh small quantities of things like topsin m, imadin etc. It works very well. They weigh in grains and 7000 grains is a pound, so it’s a very easy and accurate means of weighing small amounts