Preventing wood rot in trees--Liquid copper fungicide

sprucemanJune 17, 2008

I promised to set up a topic with a title and appropriate searchable key words explaining the situations where liquid copper fungicide and be used to prevent wood rotting fungi that can weaken and/or destroy trees. I have seen many, many trees weakened or destroyed by wood rotting fungi that entered through large pruning cuts and/or wounds to tree trunks. Most of not all of these trees could have been "saved" if the wood rotting fungi could have been kept out.

I experimented with some other fungicides. None worked except for the liquid copper fungicide. Some fungicides break down rather quickly, but liquid copper fungicide depends on the copper itself as the anti-fungal agent, and this copper is rather stable and does not break down, so it can remain active for a long period of time.

I have been using liquid copper fungicide for about 22 years on something close to 100 trees. I have used it mostly on some very large "pruning" cuts, some of which have required many years-some over 20 yearsÂto re-grow wood over the exposed wood, yet none have become infected with fungal rot. In fact, the exposed wood is still hard and fresh, without any softening after as many as 22 years. I have used this mostly on white pine, red pine, and Norway spruce, but also on a number of other kinds of trees, including red oak, ash, red maple, and sugar maple.

When and where should liquid copper fungicide be used? There are two common situations where it can be used on exposed wood to prevent fungal rot. The first is large pruning cuts. Most smaller pruning cuts to remove dead limbs or living limbs that need to be cut off for one reason or another have little risk of infection. On most healthy trees, pruning cuts less than three inches in diameter will not need any treatment, unless the tree is of a susceptible species like red maple, AND fairly slow growing. On trees like pines, spruces, white oaks, and some others, pruning cuts can be 4 or 5 inches in diameter, and in some situations even more, and if the tree is growing reasonably fast, there is little risk. But as the cuts get larger, the risk of infection increases. There is no way to quantify this risk-Âno rule about the size of pruning cut that should be treated, but I think a risk that I can imagine could be more than one percent would make treatment advisable. I will treat almost any pruning cut more than two or three inches in diameter, except on pines and spruces, because I donÂt want to take any risk whatsoever.

The other situation where treatment is advisable is injuries to the trunk of trees that result in some loss of bark and exposure of bare wood. These can become infected more easily than pruning cutsÂthere is no branch collar, which often can act as a barrier to the entrance of fungal infections. If the tree cannot close these kinds of wounds very quickly, the risk of infection is high. Especially dangerous are wounds that have some vertical length. Narrow (less than two inches) horizontal wounds that are not more than 3 or 4 inches wide are less likely to become infected. But these should be treated anywayÂthis risk of infection in these wounds is less, but still significant, and these should be treated, especially if the tree is really special.

Here is how to use liquid copper fungicide. Mix two or three parts liquid copper fungicide as it comes out of the bottle with one part water. This is much more concentrated than recommended for the regular "on-the-label"uses. Then it should be painted on with a paint brush. Use one good liberal coat so it soaks into the surface of the wood. More is not advisable. If it is for a recent injury, or a recent pruning cut of a live limb, the area should be left to dry for several months. If the sapwood is still "green," it will not absorb the fungicide. It should be used on dry wood.

It should be reapplied every year to make sure the protection is maintained. For areas of the trunk where the bark has died and/or been knocked off, it is especially important to refresh the treatment. For pruning cutsÂ-cuts across the grain of the woodÂafter about four years of annual refreshing, perhaps refreshing every other year is OK. I have not done experiments to determine just how often reapplication must be done. I am sure it would vary, depending on the kind of wood and its ability to absorb and hold the fungicide. My recommendations for annual refreshing will guarantee effectivenessÂ-at least my doing this has without fail kept out fungal infections for, as of now, 22 years.

Do not let excessive amounts soak down into the trunk of a tree. If there is any kind of area where this fungicide can collect and soak into the wood, you must be careful that this does not happen. There is some mild toxicity to the living sapwood of at least some kinds of trees. There is no benefit to having this soak deeply into the wood in any quantityÂit is a surface treatment to prevent the entrance of fungi.

This liquid copper fungicide, as far as I know, cannot be used to eliminate an established fungal infection. If wood has begun to rot, to become soft, it is too late to use this treatment. This treatment is not to be used in any hollow trunks or put into any cavities in any tree. It is likely to do more harm than good in these places.

It also cannot be used to prevent fungal infections in any wound that goes down under ground level, such as some lightning strikes. If the bottom of the wound cannot be treated and is exposed to the soil, the infection will start there and move upward and infect the main part of the wound.

What is liquid copper fungicide? Where can I get it? I have used two brands that I bought in garden shops. The one I used the most was one by Dragon. I am not sure it is still available. Another I used is by Bonide. Both of these have a water soluble form of copper. There are, I think, other brands, and some of these can be bought on-line. The key is that the copper must be in some water soluble form. Some fungicides, such as Bordeaux mixture contain copper, but it is not in a water soluble form and will not work for this purpose.

I encourage anyone reading this with the resources to do so, to do scientifically controlled experiments to help verify for all that this works. I want no citation for my idea to use this, and desire no credit what-so-ever. I just want to see trees saved. This idea is free and in the public domain.


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Excellent, Spruce. Next time I'm at my local wholesale hort. supply house, I'm going to look at their Bonide products and see what I can find. I was wondering just what this starting material is. You anticipated that question.


    Bookmark   June 17, 2008 at 9:54PM
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alexander3_gw(6 Pennsylvania)


Can you confirm the % copper in the product you use? Bonide used to sell a solution that was 48% copper, but now they seem to only have a 10% copper product. Obviously this would change the dilution factor.


    Bookmark   June 18, 2008 at 12:12AM
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Very good point. The label on the Dragon brand that I used mostly and am still using because when I heard that it might be discontinued I bought a lot of it, says that it is 48% "copper salts of fatty rosin acids." Obviously if the Bonide brand is 10% of some kind of comparable copper compound, it should not be used in such a dilute fashion if one wants to replicate what I have been doing. A 10% copper salts product probably should not be diluted at all, or if it must be for applicability needs, it should be applied in some kind of repeated fashion. Maybe applying on several days, spaced so the area can dry out between applications.

But I must admit that I did no experiments to determine exactly what concentration is needed or most effective (these experiments would be complicated and require a lot of time to get good results). I used the concentrations I did--usually something between two and three parts water to one part fungicide as it comes out of the bottle (I seldom measured exactly)--for two reasons: first, the liquid in the bottle seemed rather thick and when I first used it I used a sprayer, which required something more watery. Second, I diluted it to make it go farther because I was treating so many trees. But the dilution I was using seemed to me to be putting a lot of copper into the surface of the wood. It turned it a bright blue or blue-green color. I just felt confident there was enough copper to act effectively as a fungicide. But the color soon does fade and the wood returns to its normal color.

But when I discovered that what I was doing was working, I just wanted to keep doing it--my trees were being protected. I valued them highly, so why take any risks with experiments? I could have selected some other trees and done deliberate experiments, but I was having success protecting the trees I wanted to protect, and I have studied scientific experimental methodology enough to know that for any experiments I might do to give really valid results I would have to devote a really, really large amount of time and resources to them.


    Bookmark   June 18, 2008 at 9:24AM
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Hy spruceman,
i live in germany and i also want to test your method with liquid copper fungicide but i dont know if its available in my country. I found a link from bonide (see below). Is tihs the stuff you use? Is there something to consider (like composite) when i search for something similar in my counrty?


    Bookmark   January 27, 2009 at 11:43AM
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Yes, Bonnide makes a liquid copper fungicide that you can use. But note the post by Alex above, where he says the formula has been changed to just 10% copper salts. If you get a formula like this, I would not dilute it, as I suggest above.

I am glad you are going to try this--it really prevents rot from entering trees, with the few limitations I note in my main explanation above. It is a shame that so many trees are damaged or destroyed by fungal rots, when they can so easily be prevented. Spread the word over there--there are mostly skeptics here, but I can't blame them--we really need research by some recognized person/university to confirm all this. People need to know that the spruceman is not a kook (slang for idiot).


    Bookmark   January 28, 2009 at 7:25PM
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arktrees(6b NW Arkansas)

Perfect time for this thread to come back to the top, as we have had a devastating ice storm here in northwest and north Arkansas (I just got power back a couple hours ago), and so many trees have had HUGH limbs torn away. Incredible amount of damage. I saw a large beautiful blackgum tree (about a 24-30" diameter trunk) that I have been looking at for a few years on the University of Arkansas, and it has taken allot of damage. Not nearly as bad as many trees (and let not talk about the Bradford Pears, but I didn't know a tree could just leave a stump sticking up like that).

I'm going to make sure some people see this in hope os helping.


    Bookmark   January 29, 2009 at 12:04AM
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Sorry to hear about the terrible damage. I do think that the liquid copper fungicide can help. Some of the wounds you are talking about may be so large that they will take a very, very long time to "heal" over, if ever. But I have a few trees I have treated that had very large pruning cuts/wounds over 20 years ago and there is no sign of any rot yet. And these are trees with soft rot susceptible kinds of wood.

But one problem you may face when very large limbs are torn away is at the base of the wound to the trunk. Often the limb tears away leaving a kind of flat area or a kind of "pit" at the bottom. This can be difficult to deal with. If the area can be cut away so that the bottom area can be smoothed out and so the water will drain off and not pool in or on this area, it would be good. To be honest, I am not sure how this treatment will work with some of the more extreme wounds of the kind that happen when a branch is simply torn away from the trunk. If the area is not smoothed out so the water drains off it, there can be two problems. First, this constant soaking without properly drying out may prevent the liquid coper fungicide from working to prevent the rot. I have never treated any wounds like that, so I can't make any claims. And, another problem is, if more than just a very little of the liquid copper fungicide is allowed to soak down into the sapwood at the base of a large open wound like I am talking about, it can very possibly kill the sapwood immediately beneath. This would not be good. Even if you can trim the bottom of the wound as I say, the grain at this point is upward and the cut is across that grain. So any application, and repeat application, must be very light--just enough to thoroughly "paint" the area blue with the fungicide. Otherwise, the fungicide can easily soak down too deeply. And, in situations like this, I recommend using a lot of brush work to get the coating, rather than adding more fungicide. But, on the other side, you do want to have the fungicide soak into the surface, and the sruface only, just a bit. Higher up on the wound area, you need not be quite so careful.

But with these limitations/warnings, I think that the use of liquid copper fungicide can save many, many trees after a storm like you have had. Even some very large wounds that one might think could never "heal" over, can be kept free of rot for at least 20 years, and my guess, from the present condition of some trees I have been treating for that long, much, much longer.


    Bookmark   January 29, 2009 at 10:25AM
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This reply is just to renew this topic, so it is not "timed out." Does anyone know how long a "dead" topic is retained before it is chucked?


    Bookmark   July 18, 2009 at 11:09AM
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alexander3_gw(6 Pennsylvania)

The list at the bottom of the forum page (below all the thread titles) goes to page 67...those messages are from July of 2008. The search function will pull up older threads, at least as early as 2006. There is a FAQ for this forum, but I don't see how to add items to it.


    Bookmark   July 18, 2009 at 9:38PM
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franktank232(z5 WI)


Excellent topic. I need to make a fairly large pruning cut on a peach tree of mine (which you probably know are VERY fast growing) and i plan on waiting until late winter/early spring. I already have a bottle of Bonide i got a few years ago.

Here is the Bonide product. Its in liquid form.

    Bookmark   July 19, 2009 at 11:22AM
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Thanks for the photo--I had not seen the Bonide product for a long time, and it has been changed from what I used. The specific brand I used most of the time was one made by Dragon, but it has since been discontinued.

This leaves me with some questions. Bonide calls their active ingredient a "copper soap." I am not sure what this is and don't know if it has the same kind of activity as the Dragon brand I used, which was described as a mixture of "copper salts."

I would have two concerns about the changes in the formulations. First is the actual elemental copper content. I still have some of the Dragon brand I used, but don't have a bottle handy so I can read the label right now. If this elemental copper content has been reduced--and I suspect it has been--then I would not dilute it as I recommended for the original Dragon brand I used. Second, I would be concerned that it might not be so "sticky," and may wash off more easily in rain. Maybe to be on the safe side, you should refresh it more often--maybe every six months.

I think the Dragon brand was discontinued because of concerns about its safety. Perhaps some of its effectiveness was because of the toxicity of some of its ingredients. As time went on and the trees I treated 20 years ago showed no sign of any rot or wood softening whatsoever, I realized that the product must not only kill fungi, but also bacteria, which can cause their own kind of rots.

But, in spite of the new formulations of "liquid copper fungicide," I still think it can be effective. The original reason I chose to try it was because it is the elemental copper itself that is the fungicidal factor, and copper is stable--it won't break down and lose its power easily. I tried things like Captan, and either they did not kill the fungi as effectively, or the compound used broke down quickly and lost its power.

In any case, I am sorry that the product has been very basically changed. I guess at this point I can't promise the results I have had with the products I have been using for so long. It could be that the new products will be just as effective, but I am sorry I can't guarantee that they will be.

Obviously, this is very disappointing to me. Perhaps the old Dragon product, and others like it, could be safely used in the way I used them--I did not use it on any food crops, but simply in very localized and limited applications on the wood of trees.

Well, use what you have and report back to us what results you see. If you see any kind of fungal fruiting bodies appearing, or at least see that the wood of the pruning cut begins to soften, then the product has failed.


    Bookmark   July 19, 2009 at 3:45PM
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With a lot of regret, I am finally forced to give up my attempts to help tree lovers save trees by preventing wood rotting fungi from entering trees through large pruning cuts and wounds to the trunks of trees.

Dr. Shigo, whom I consider more or less of a fake who did little real research, has for now won the day. Statements like this recent one recently posted represent the prevailing view:

"In general, trees can "compartmenalize" (wall off) wounds that are under 50" of the circumference of the tree. DO NOT APPLY ANY WOUND COMPOUNDS TO THE INJURY--LET IT SEAL ITSELF OFF!"

There is some ability in trees to wall off fungal rot infections, at least for a time, but this ability is very limited when it comes to large pruning cuts and larger injuries to the trunks of trees. I have observed the damage done to trees by rot entering these injuries for many, many years. Sooner or later, these rots cause the premature death of the trees they have infected.

The Dragon brand of liquid copper fungicide that I used for many, many years is now off the market. Bonide used to make a generally similar product, but the liquid copper fungicide they now make seems to me to be a completely new formulation. I think there is a chance that the new kind of liquid copper fungicide that is now available on the market will work, but I dont have any experience with it.

I could start some new experiments to see if it could work, but that would take many years to get useful results, and because I still have several bottles of the old Dragon brand, and because I know it works, I will continue to use it on my trees.

If I were to do some new experiments, I would try the new kind of copper fungicide. And I might try to use it in combination with some kind of wood preservative, and/or use it mixed with water soluable copper sulfate, which one might be able to purchase separately. Obviously there are lots of possibilities.

It is very, very sad that Dr. Shigo has had such a pervasive influence. The wood rotting fungi, and the bacterial rots, that enter trees are often entirely preventable. Probably sometime in the future this will be clearly understood, and someone will produce a product that will do the job. The old kind of Dragon liquid copper fungicide absolutely worked, but it is now gone. I am sorry, but I can no longer, with any confidence, make any recommendation for anything to prevent wood rotting fungi from entering trees.


    Bookmark   July 20, 2009 at 10:30AM
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dan_staley(5b/SS 2b AHS 6-7)

As I wrote somewhere else here, I spoke at a conf in Dallas this past spring and there was a guy there who went just before me who said about the same thing, but didn't stick to a particular chemical application. I had some conversations earlier with folk who weren't happy he was there and questioned his results.

Well, I had to pay attention to the guy because I was there ready to go, and I must say his methods IMHO lacked sufficient rigor, his ns were too low for me, and his results were mixed. Yet he was willing to say based on his results he didn't believe Shigo either. Now, one of my undergrad buddies was there as was my undergrad advisor and we spent about 72 seconds discussing how his presentation didn't work for us then we moved on.

So. Bottom line: your data will tell the tale. If you don't have the data, you can't tell your story for folks to listen. There's two parts: your results and how you tell others about them. If the data are compelling, write them up and send them to SAF, ISA, etc trade pubs and keep at it. Save all your rejection letters and keep at it (when people ask me what I'm doing I sometimes say 'collecting rejection letters'). Write it up and keep at it. It doesn't happen overnight, and I can tell you lots of things about who doesn't get what. Don't give up. Ever. Humanity and society is slow to get it and slower to act - it is the human condition that societies don't act unless there is a threat/motivation, galvanization and organization.


    Bookmark   July 20, 2009 at 11:16AM
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toronado3800 Zone 6 StLouis(6)

we should find a mature field of silver maples. Make 1000 various cuts in them. Then treat half and leave the others to sit there exposed.

    Bookmark   July 31, 2009 at 8:39PM
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brandon7 TN_zone(7)

Toronado, what will we use to treat the "treated half" with?

    Bookmark   July 31, 2009 at 9:24PM
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What to treat the other half with? Well, If I were 45 years old again and had just bought the woodland with the pine and spruce groves, I would use the newly formulated liquid copper fungicide. My original theory was that the copper in this general kind of fungicide is persistent.

Will it work as well? I dont know--maybe. But I see a couple of potential problems. I may buy some of this stuff, and see just how "sticky" it is. The original kind I used was the one by Dragon, and its active ingredient was "copper salts of fatty rosin acids." Well, I am not a chemist, but "fatty rosin" strikes me as something that is sticky. And I can report that this stickiness is apparent immediately--it is hard to wash off the paintbrush I apply it with. Now the new formulation is called "copper soap." Again, I dont know exactly what that is, but it doesnt sound so sticky, so it may not be so persistent and not work very well. I can say you could try it, but I cant promise results. The other brand I used a couple of times when I couldnt find the Dragon brand, was one made by Bonide. I dont have the label any more, but whatever was in it, it was even stickier in at least one respect than the Dragon brand.

The other problem is that the original formulation with the "copper salts of fatty rosin acids" has some general toxic effects that the new "copper soap" may not have. After years of my refreshing the applications on very large cuts on pine and spruce trees, I noticed there was virtually NO deterioration of the wood whatsoever. Now this made it clear to me that something other than fungicidal action was at work. Wood also rots from bacteria. So this original kind of liquid copper fungicide I was using was also stopping bacteria.

Can I write any letters reporting my "experimental results? No. Nothing I did really qualifies as any kind of experiment that I could report. I had absolutely no "controls." But I can say that at first I used other things to try to prevent rot from entering the kind of cuts I was making on my trees. These were all a kind of cut that was extremely susceptible to fungal rot infections, and as far as I know, all of them showed undeniable signs of fungal infection within two years or less--little fruiting bodies and all. So I am as sure as I can be about anything in this old world, that this stuff prevented fungal, and even bacterial rot--as of this year for well over 20 years. But I can't claim to have any proper experimental results.

The large majority of the cuts I made are now "healed over," but a good number were so large and/or were on slower growing trees, that the wood is still exposed. Some of the cuts are also younger--10 years old or so, and thus have not "healed over." If anyone with a serious interest wants to see these trees, send me an e-mail.


    Bookmark   July 31, 2009 at 10:22PM
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If you like the results of the Dragon brand, there is another product registered in Virginia with 58% "copper salts of fatty rosin acids"...its called Camelot (SePRO makes it), but it comes in a 1 gallon container. I am not familiar with Dragon brand, but Bonide is a line marketed towards homeowners....Camelot is marketed towards greenhouses, nurseries and landscapers. It has been around for several years

    Bookmark   August 1, 2009 at 10:04AM
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Wow! We are back in business!! I will call them and tell them about my results and see if they are interested in getting it approved for use on trees to prevent rot.

But I am surprized. I saw on the internet when I did a search what seemed like an EPA action against this kind of fungicide, explaining, I thought, its discontinuation by Dragon and others.

Thanks--I will follow up on this!!


    Bookmark   August 1, 2009 at 10:28AM
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brandon7 TN_zone(7)

I meant to add this before, but forgot...

"Soap" or "true soap" (found on the label of some other brands) is the exact same thing as "copper salts of fatty rosin acids" (like from the Dragon brand). Different brands may have different concentrations, but the different names for this ingredient don't indicate a difference.

Also, I noticed this thread didn't come up in a search. I have no idea why. I'm hoping that by reposting to it, it will somehow get back into the queue.

    Bookmark   February 24, 2011 at 3:42PM
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viburnumvalley(z5/6 KY)

Maybe another posting will help...

    Bookmark   March 11, 2012 at 10:33AM
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brandon7 TN_zone(7)

Bumping up again, in hopes this thread won't get lost.

    Bookmark   August 13, 2014 at 10:12PM
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tenacre(Z5 SW MI)

Hi spruceman,

I hope the following explanation will help answer some of the questions you asked:

Copper octanoate ("true copper soap") and "copper salts of fatty and rosin acids" are not the exact same thing.

In chemistry, "soap" is a technical term which refers the salt of a fatty acid.

Octanoic acid is a fatty acid. Copper octanoate is the copper salt of that particular fatty acid. Therefore copper octanoate is a true soap.

"Copper salts of fatty and rosin acids" is a mixture which contains copper salts of (unspecified) fatty acids and copper salts of rosin acids.

Camelot contains 58% "copper salts of fatty and rosin acids". It also contains Xylene solvents. (Xylene is used in some paints) .

CamelotO contains 10% Copper octanoate (copper soap) and 90%
inert ingredients (probably water).

Those 2 products do not use the exact same chemicals. As you said, whether or not they are similar enough to give the same excellent results you have observed over many years is an open question.

    Bookmark   August 15, 2014 at 4:51PM
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brandon7 TN_zone(7)

Many, many data sheets throughout the industry give the same information I quoted in the other thread. You can trip over the words, but that doesn't change the fact that the chemical we are talking about is the same. I wasn't trying to say that the products were the same. I was saying that the ingredient we are concerned with is common to both products. While it's true that the success of one product doesn't guarantee the success of the other, it does suggest at least a strong possibility.

    Bookmark   August 16, 2014 at 12:46AM
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tenacre(Z5 SW MI)

> Posted by brandon7 6b/7b TN Fri, Feb 25, 11 at 0:05
> "Soap" or "true soap" (found on the label of some other brands)
> is the exact same thing as "copper salts of fatty rosin acids"

Copper octanoate (copper soap) is not "the exact same thing" as copper salts of fatty and rosin acids. They are different.

> brandon7 7 TN Sat, Aug 16, 14 at 0:46
> the chemical we are talking about is the same

They are not the same. Copper octanoate (copper soap) is not the same as copper salts of fatty and rosin acids.

> brandon7 7 TN Sat, Aug 16, 14 at 0:46
> the ingredient we are concerned with is common to both products

The ingredients being compared are copper octanoate and copper salts of fatty and rosin acids. They are not the same thing.

Stop spreading misinformation and confusion.

    Bookmark   August 16, 2014 at 1:49AM
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I believe that my tree can be easily treated without all the confusion shown above.

    Bookmark   August 16, 2014 at 2:01AM
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whaas_5a(5A SE WI)

Yes, and that magic answer is leave it!

As Tom eluded to in this thread or the other copper thread its rare to see decaying wood where plants aren't covering their wounds. Only time I see this is in forests or road sides that were damaged or infested with pest or disease. I guess this makes sense for someone that has a timerland or many acres with trees. Still don't understand why pines and spruce would need this as they usually, from what I've seen, immediately and quickly excrete sap.

By no means discounting anything regarding this application just don't think its needed as much as elluded to in this post.

Perhaps region has at lot to do with whether this is needed as the rule vs the exception.

    Bookmark   August 16, 2014 at 11:04AM
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Yes, pines and spruces can exude sap, but that sap is not enough to cover large wounds, and even if it were, it would not prevent rot. Pine sap can for a time can create a barrier that can delay fungal infections, but it is not itself a fungicide. In fact, I have had a lot of experience with large wounds to both pines and Norway spruce trees--the fungal rots enter these trees faster than in most, and the rot spreads very, very fast.

Before I hit on the liquid copper fungicide, I experimented with Captan, and with Bordeaux mixture. With both I saw fungal fruiting bodies within two years--maybe just 1.5 years.

But, if one prunes off smaller side branches from pines and spruces, there is virtually no risk of fungal rot entering those kinds of cuts. With red pines especially, the cut surface is impregnated with pitch, and is very, very rot resistant. But this is not the kind of situation I am recommending this fungicide treatment for.

The cuts I made on about a dozen white pines, for example, were to remove 1/2 of a forked tree, and the cuts were generally about 8" by 12". My forester who saw what I had done said that I was wasting my time trying to save such trees. Hah! He should see them now.

White pines with a tight "V" shaped fork will eventually split in storms about 90% of the time, hence my acting to save them. Every one of the trees I cut this way about 27 years ago is now a beautiful, straight white pine tree, 100 feet tall, and as healthy as any tree can be.

I have also had a few white pine and spruce trees clawed by bears, leaving large areas with the bark removed. I have treated these trees also, and no rot has appeared in these either. With the spruce, sap did cover a part of the damaged areas. With the white pine, sap actually covered very little. But, even had the sap covered these areas, there would have been a delay of just three, or maybe up to 5 years--not nearly enough time for the callus to cover the wounds.


    Bookmark   August 17, 2014 at 4:40PM
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