Can't stop myself from answering you on this though meushi.

Label me stupid if you want, but if I was trying to reach an exact concentration of auxin for a tree I'd rather use auxin not pre-diluted in undisclosed ingredients in unknown quantities and with instructions as vague as "3 fl oz per 100 gallons is optimal for most cases". I'd rather use a known "pure" auxin at a pre-established concentration.

Auxin is used in very small dilutions. I have worked out from the active ingredients list and the recomended dilution for Repotting Transplanting of ornamentals and shrubs. That the dilution recomended is 0.000002 grams per litre. So if you can work that out from a pure auxin and a known dilution specific to species I would not call you stupid, I would call you to start production of the new miricale potion

Brett,

I specifically said "at a pre-established concentrations", by "pure" I meant not mixed up with fungicides or other unknown/unspecified additives. If you want to blow your money on "unspecified ingredients in untold concentrations", you are free to do it... especially when the manufacturer kindly provides the one gallon label for anyone to print and stick on a bottle. As I said before, if I need auxins, I'll stick to the commercial powders available in a range from 0.1% to 4.5% IBA, thank you very much.

Michael

Okay sorry meushi I did read the post a couple of times as I was unsure what you meant by pure. The products I stated often called plant starter are just that. Auxin diluted down to a managable level my guess is with water? But Auxin is the only active ingredient and the concentration is clearly labeled. Superthrive is to but harder to find.
You can find multi crops on this page.
http://www.multicrop.com.au/accessor.htm
I use one called Nuserymens Brand Plant Starter. $10 for 1 litre with mixing rate of 2ml per liter of water. So it will not break the bank.

I agian see the problem with the rooting hormone powder made for rooting cuttings as being hard to get the dosage right but many people do use it this way. I have heard of many stories of growers sprinkling some in the soil when repotting. I find that a little scary as getting the dose wrong can kill a tree.

Regarding Will's article.

I was told some years back by a local arborist that cut paste is unnecessary and if anything is more likely to encourage rot due to it's tendency to encourage moisture retention. I have accordingly always left my pruning wounds uncovered to no ill-effect. I am curious, however, if there are exceptions, such as trees that are moisture sensitive (like some Hornbeams) or those which bleed excessively (like Maples). Are there times where the risk of potential pathogens is outweighed by the potential benefits of less die-back?

I'm pretty new at this still so any informed opinions on the matter would be appreciated.

Thanks,

Jeremy

I've not used any wound dressings for normal pruning for years, but this article makes me think, which means it is doing what it should.
It is fact that Nature prunes rather severely at times and provides no sealer. Nature, however, does not rip a tree from the earth, slash off 2/3 of the roots, slash off 2/3 of the foliage, and then replant the tree. One of our goals when we do this (apply cut paste) to a tree is to do exactly what one of the researchers said "Seal moisture in"
Can we make the case, in this situation, to use cut paste temporarily? Vic

It is really good that Will brought this article to us, no doubt at all. My take is that we should always seal with cut paste if the wound is bigger than your little finger nail on deciduous trees. I even do this on junipers but not on pines, as they seal by themselves.


Ash

As Will knows, I'm always ready to cross verbal swords with him, but I agree with one of his contentions....

Superthrive may or may not work. The problem is that the claims made by the manufacturer are far-fetched, largely unintelligible and totally unsubstantiated. This has led to its being prohibited for sale throughout Europe (officially, at least). Why?... Because the European consumer protection legislation prohibits advertising or packaging statements that cannot be proven. If the claims made by the Vitamin Institute of California were true, surely they would make their research available and take advantage of the considerable European market. Having said that, I have used it and may use it again, but only because in makes me feel better.

On the other hand...

Foliar feeding is an area where experts disagree. In Europe, foliar feeding must be considered to work - otherwise that too would be banned for the same reason that Superthrive is. I have no idea what research has been done, but you can guarantee that the consumer protection nazis have done their homework and that any fertilizer that is claimed to act through the leaves, does just that.

Cut paste has always been a bone of contention with arborists. Dr Shigo is absolutely correct when he claims a pruning cut which retains the collar will seal quicker and more soundly than a more flush cut. On a full size tree. He did no research whatsoever into bonsai, and Will has failed to acknowledge the difference. Look at any well-pruned (Shigo technique) landscape tree and you will see bumps where the pruning cuts have sealed. They look okay and tend to disappear in time, but we are growing bonsai and we don't want lumps and bumps all over our trunks. Leave the collars when you prune and you will get a very ugly bonsai.

Cutting flush without using a sealant causes dessication of the tissue immediately around the wound, effectively enlarging the wound and delaying the growth of callus. Whether or not cut paste contains fungicide or any other magic potion is irrelevant - its purpose is to prevent dessication of the surrounding tissue so that the callus begins immediately at the cut edge and grows rapidly. It's all very well and good to say that you never use cut paste and your pruning cuts seal over okay - but how much better would the seal if you had used cut paste? You have to try both many times to know - and I, many others, and generations of Japanese bonsai growers have. And we all use cut paste.

Colin

HoYoku wrote:As Will knows, I'm always ready to cross verbal swords with him....

Likewise, intelligent debate with you always leads to a better understanding of the subject.

HoYoku wrote:Foliar feeding is an area where experts disagree. In Europe, foliar feeding must be considered to work - otherwise that too would be banned for the same reason that Superthrive is. I have no idea what research has been done, but you can guarantee that the consumer protection nazis have done their homework and that any fertilizer that is claimed to act through the leaves, does just that.

I do not argue the point that leaves can and do absorb nutrients and minerals, however the effectiveness of foliar feeding is well below that of traditional soil feeding. Allow me to quote a few lines from my article:

"The problem is that most of these claims are based on some research done by Michigan State University in the 1950’s in which, by the use of raidolabeled nutrients, it was determined that the leaf is a very efficient organ for absorption. The amounts absorbed were actually very low but the efficiency was high, leading to false claims that foliar feeding was many times more effective than soil applications.

Linda Chalker-Scott, an Extension Horticulturist and Associate Professor at the Puyallup Research and Extension Center of Washington State University, clarifies this in her article, "The Myth of Foliar Feeding."

"Obviously, materials applied directly to a leaf are more likely to enter the leaf in large quantity than the same materials applied to soil. Leaching, chemical reactions, microbial activity, etc. can decrease what actually reaches the roots and is taken up into the plant. But material applied to the leaf do not necessarily travel throughout the entire plant as effectively as they do through root uptake. The often remain in the same or adjoining tissues but travel no further. This is especially true of those elements recognized as "immobile" within plant tissues (apart from root uptake and xylem transport)."

Linda goes on to state that the nutrients plants need the most of are the very ones that cannot be absorbed in large enough quantities by the leaf to do any good, such as nitrogen, phosphorus, and potassium."

Your "consumer protection nazis" no doubt allow foliar fertilizer sellers to claim the nutrients are absorbed through the leaves, as they are, however claims that such is more efficient than traditional soil feeding would be false, and provable by research.


As to cut paste, I am awaiting some more information and I hope you do not mind if I address this issue in a few days. I will address the following statement you made however.

"You have to try both many times to know - and I, many others, and generations of Japanese bonsai growers have. And we all use cut paste."

Generations of Japanese growers also used layers of soil particle sizes in their pots, earth dug from at least three feet underground, peat, leaf mold, compost, and at one time they never used wire at all.

They also never foliar fed.

In my copy of "The Japanese Art of Miniature Trees and Landscapes" by Yuji Yoshimura and Giovanna M. Halford, there is no mention of using cut paste or any other sealer at all when pruning a bonsai, instead Yuji recommends slightly concaving the pruning area so the tissue will heal level, without an unsightly bump.



Will

I was thinking about this and Linda today. I have found linda's writings very informative but I have started to read between the lines a bit when I noticed she often states lots of research but never references her work. This seems very strange for some one of her stature??
Linda Chalker-Scott, an Extension Horticulturist and Associate Professor at the Puyallup Research and Extension Center of Washington State University
Some of her myth busting almost contradicts itself. It seems she leaves stuff out of one topic but it turns up in another.
Lets look at one of her statements.

Naphthylacetic acid (NAA) is also a commonly used auxin and often the active ingredient in commercial
preparations. NAA tends to be toxic to seedling root development, as it inhibits primary root growth and
enhances lateral root growth. This latter activity may account for NAA’s success in regenerating roots of
transplanted and root-pruned trees. Like IBA, NAA apparently suppresses crown growth, which also may
redirect resources to the roots.

Sorry this is about Auxin but It is a known statement that I have trouble with.
NAA tends to be toxic to seedling root development, as it inhibits primary root growth and
enhances lateral root growth.
To stop primary root growth and enhance lateral root growth is generally what auxin does this may not be good for general nursery use but it sounds great for bonsai seedling development.
My main issue with Linda's words here is Toxic were is any proof that auxin does this because it is toxic.?
Then
This latter activity may account for NAA’s success in regenerating roots of
transplanted and root-pruned trees.
Since this section of her article is all about What does stimulate root growth.
In all fairness Linda could have written NAA has had success in regenerating roots of transplanted and root pruned trees. This may be from inhibiting primary root growth and enhancing lateral root growth
I feel alot of her writting is emotionaly biased. This coupled with her lack of referencing leads me to often read between the lines to get the real facts.

You have a point brett, without citation of studies that show that it's toxic you can't really say that it is...........