killing microorganisms

Hi all.

Pls. help me clarify something. Do inorganic/chemical fertilizer kill the microorganisms in the soil?

I have read in the internet that using inorganic/chemical fertilizer can kill the microorganisms found in the soil which are responsible in the decomposition process. It's because I'm using fish emulsion and liquid seaweed extract, and miracle grow alternately. I'm just afraid that my time and effort would just be wasted if I'm going to use the organics (which I assume would increase the activity and population of microorganisms) then apply the inorganic. Which would eventually kills the microorganisms. I'm using 1 part cat litter, 1 part pumice and 1 part vermicompost. Is my feeding regimen alright or do I have to choose either organic or inorganic?

Thanks.

Warren

I don't think I'd worry too much. This is going to make a lot of people here huffy, but the value of mychorizza fungi to bonsai has been vastly overstated.

Our soil is (or should be) most inorganic -- which is hostile to mychorizzal fungi. We transplant and replace our soil with great frequency -- also hostile to mychorizza. We give our trees all the fertilizer they need, thus eliminating the most valuable function that mychorizza provide in nature -- helping roots gather nutrients from barren soils.

While it certainly doesn't hurt our trees if mychorizza show up in our soils, it's no big deal if we don't have any, either. So use whatever fertilizer procedures or combinations work for you.

Ok now I get it. Thank you Jim.

Warren

First of all, your fertilizer will not affect microorganisms in the soil.
Jim, I think he was referring to soil bacteria that are responsible for the decay of organic matter. Mycorrhizal (sic) fungi are inside or right on the roots. If you have to use a soil fungicide drench, that would damage your mycorrhizae, but if you had root rot, it might be necessary.
Warren, conditions in the tropics may be entirely different, but in this part of the world, we don't particularly want the organic component of the soil to decay very fast, because that leads to compaction & we have to repot. Does your soil mix drain rapidly?
I used to be very skeptical of the value of mycorrhizae to bonsai, but the tree extension lady found me several references to studies that showed the use of mycorrhizae reduced the need for fertilizer in container plants. This was mainly useful to the nursery trade, but it might have implications for bonsai. I use Micro Plus, a combination of trace elements and mycorrhizal inoculant. I have been using it mainly on conifers, but I will try it on some other weak trees. It definitely prevents attacks by tigers.
Iris

I want to add that mycorrhizal inoculant might be helpful to succesfully grow conifers, specially those from temperates areas.

Conifers do not have the mycorrhizal organisms in their roots, but in the soil. They help the plant to process the nutrients from the soil. These organisms are indigenous to the areas so they tend to be incorporated to the soil even when used as barren as stated before. For this plants, it certainly aids to make them grow faster to add some inoculant mix. I used to grow firs, junipers and pines down here in the Caribbean area, but they don't thrive if you don't inoculate the soil periodically. Very few conifers tolerate tropical weather or being without a wintering period.

In the tropical weather, you do not need inoculants. Your trees grow with these mycorrhizal organisms inside their roots.

drjmarrero wrote:I want to add that mycorrhizal inoculant might be helpful to succesfully grow conifers, specially those from temperates areas.

Conifers do not have the mycorrhizal organisms in their roots, but in the soil. They help the plant to process the nutrients from the soil. These organisms are indigenous to the areas so they tend to be incorporated to the soil even when used as barren as stated before. For this plants, it certainly aids to make them grow faster to add some inoculant mix. I used to grow firs, junipers and pines down here in the Caribbean area, but they don't thrive if you don't inoculate the soil periodically. Very few conifers tolerate tropical weather or being without a wintering period.

In the tropical weather, you do not need inoculants. Your trees grow with these mycorrhizal organisms inside their roots.

Even the mycorrhiza that is in the soil is attached to the roots, research show if once a tree hase this fungii its no use to inocculate it, with repotting you never cut all the mycorrhiza, it should grow out again after a couple of days, I never use inocculants or old soil, and al my pines growing media is filled with the fungii.
Jim, once again we disagree, My opinion is that trees with mycorrhiza are stronger and the abillity to uptake of nutrients is better.
Your wright if it is a species that is not so bound by mycorrhiza and its bennefits.

Peter

bonsaisr wrote:First of all, your fertilizer will not affect microorganisms in the soil.

Warren, conditions in the tropics may be entirely different, but in this part of the world, we don't particularly want the organic component of the soil to decay very fast, because that leads to compaction & we have to repot. Does your soil mix drain rapidly?

Iris

I think it drains fast (water stays in the topsoil when directing the water hose for some time then drains after about 2seconds) but not as fast as the or inorganic soil mix.

landerloos wrote:

Even the mycorrhiza that is in the soil is attached to the roots, research show if once a tree hase this fungii its no use to inocculate it, with repotting you never cut all the mycorrhiza, it should grow out again after a couple of days, I never use inocculants or old soil, and al my pines growing media is filled with the fungii.
Jim, once again we disagree, My opinion is that trees with mycorrhiza are stronger and the abillity to uptake of nutrients is better.
Your wright if it is a species that is not so bound by mycorrhiza and its bennefits.

Peter

How do we know that mychorrhiza is present in the soil?

JimLewis wrote:I don't think I'd worry too much. This is going to make a lot of people here huffy, but the value of mychorizza fungi to bonsai has been vastly overstated.

Our soil is (or should be) most inorganic -- which is hostile to mychorizzal fungi. We transplant and replace our soil with great frequency -- also hostile to mychorizza. We give our trees all the fertilizer they need, thus eliminating the most valuable function that mychorizza provide in nature -- helping roots gather nutrients from barren soils.

While it certainly doesn't hurt our trees if mychorizza show up in our soils, it's no big deal if we don't have any, either. So use whatever fertilizer procedures or combinations work for you.

Bonsais are apolitical when it comes to fertilizers, it wont mind if its organic or chemical
fertilizer..Pabling

If it is present in the soil you usually can't miss it. For pines especially its presence is so beneficial that I can usually tell by looking at a tree if the roots are being aided by myccorhizae. It will colonise the surface, especially the root/pot interface with a creamy coloured very fine mesh that can resemble wooly root aphid. Once you can spot the difference, it is obvious. I often place a small flat stone on the surface of pots, so that I can intermittently lift it off and check for the telltale myc. I do add a pinch of healthy myc to just below the soil of trees (of the same species) that aren't showing signs of any, and more often than not it works.

Waba, do not be too worried about this area. Almost all the plants you are going to be working with have little problem with their soil's environment.

You have to worry more about your watering and feeding methods, and your soil mix. Check with your local bonsai club.

waway wrote:
I think it drains fast (water stays in the topsoil when directing the water hose for some time then drains after about 2seconds) but not as fast as the inorganic soil mix.

I am very hesitant about making suggestions to you, because I know how I feel when experts from the tropics try to tell me what to pot my bonsai in, having no understanding of my growing conditions. However, I am a little concerned about the worm castings as your organic component. If that is your only possible source of organic matter, so be it. How fast do your trees dry out? If you have any problem with soggy soil, perhaps you can just increase the proportion of pumice. As somebody else suggested, check with your local bonsai club about recommended bonsai soil. I agree with Dr. Marrero.

Recent research has found that virtually all trees use mycorrhiza (note spelling). When I repotted my long-neglected pomegranate (see thread by that name), my instincts told me to add mycorrhiza, so I did. Now I just Googled up a study where they found that pomegranates given mycorrhiza grew much better than those without.
Iris

Just questioning a bit of your logic Jim.

Our soil that is "hostile" to the fungi holds little water, and retains few nutrients..Agreed. (could be considered somewhat hostile to our trees too).
Given that the soil holds few nutrients, why would we not want to encourage the beneficial fungi? Afterall, we should each be trying to optimize growth and health...as opposed just keeping them green. Besides that "vastly" is a pretty broad assumption with so much other contrary evidence and experience out there.

I can say from personal experience my trees do grow better when I use certain organic fertilizers which have been proven to assist micro organism growth. ie rapeseed cakes and or cottonseed meal. No controlled experiments, just careful observation of how my plants are growing.

Neil

I said that people will get all huffy about this, but I'll stick with what I've said.

I've never been in either place, but Tulsa may be a different growing environment from North Carolina, & their soil mixes may be different.
There is an old Jewish story: Two men went to their rabbi with a dispute. The first man tells his story, and the rabbi says, "You're right."
The second man says, "Wait a minute, you haven't even heard my side of the story," and proceeds to tell it.
The rabbi says, "Yes, you're right."
A fellow at the back of the room pipes up, "Rabbi, this doesn't make sense. First you tell one guy he's right, then you tell the other one he's right. They can't both be right."
The rabbi answers, "You're right too."
Iris

Happy Birthday, Jim.
Thank you for everything you do for this forum.
Iris

Jim,
Not so much getting huffy, just challenging the logic behind the assertion that micro-organisms simply do not matter. Good for you sticking to your guns.

Iris,
Good story, I have heard that one before. Benefits of fungi and tiny critters are one thing to agree to disagree on, soil is another can of worms all together and I ain't opening that one...no way!

Neil

Jim, Not to get huffy but when you are wrong, you are worng (which is frequently it seems)

Approach the concept of Microrhyzae logically. These are tiny fungi that live in a symbiotic relationship with the trees roots that increase the efficiency of a trees nutrient uptake. Efficiency is the key word. They are both endo and ecto types and the types are usually specific to a tree species. Say a tree with no microrhyzae has X quantity of roots. Assume those roots can only absorb Y nutrients, yet if they were available to the rest of the tree, the tree could use Z nutrients. Z is greater than Y. Even if you surround the roots with constant nutrients, the roots can only absorb Y. So the tree doesn't develop as quickly as possible. The effect of the microrhyzae is to improve the efficiency of nutrient take up of the roots. So now the tree can potentially absorb many times more than Y nutrients and approach Z. Faster developing trees means faster attainment of bonsai design. It usually means healthier trees. Better growth up top means more roots develop and more roots with microrhyzae will further improve the development of the tree - like a miniature chain reaction.

Pine trees in a pot are a species that particularly respond well to ectomycorrhizae. Pine trees usually don't like to have their roots remain wet all the time so it is not wise to flood them with nutrient water all the time in order to maximize nutrient uptake. A full colony of microrhyzae will therefore greatly expand the nutrient uptake that the tree can "grab" while being watered. I believe in the past you have said you don't work with pine trees, so maybe you have not had the personal experience to witness its benefits. I have. For example, I have just finished working in my garage with a Japanese Black Pine tree that for years did not seem to have any visible microrhyzae and was not growing as well as I would have liked. Last repotting I inoculated it with "Tree Saver" a commercial product and the growth difference with the inoculation is very noticeable.

Not being one to rely on anecdotal evidence, here is one article written by a biologist that has studied the effects of microrhyzae especially in the nursery trade and in containers. http://www.forestpests.org/nursery/mycorrhizae.html To summarize the article - it is very valuable.

Well, I'd always heard that "you can always tell an engineer, but you can't tell 'em much."

I think logic and biology (of which I used to be one, long, long ago) are on my side -- at least as far as bonsai pots and soil goes.


Thanks, Iris.

I researched the topic of mycorrhiza a few years ago while preparing for a talk on soils. The symbiotic relationship that Rob describes is certainly accurate and beneficial for most species. Electron and light microscopic imaging of roots with mycorrhizal colonization is impressive, effectively increasing the surface area available for nutrient uptake. Azaleas are less likely to benefit from mycorrhizal growth, perhaps due to the very fine, spreading nature (i.e. large surface area) of healthy azalea roots. In addition to increased surface area, enzymatic reactions will also help make nutrients more available.Mycorrhizal innoculation will be particularly helpful in soils which lack nutrients, especially phosphorus, or sufficient moisture. Indeed, it has been demonstrated that attempts at innoculation with mycorrhiza will fail if the prevailing soil phosphorus level is very high.
In container growth where we carefully control soil particle size, composition, added nutrients and moisture, the benefits of robust mycorrhizal growth may not be dramatic, but there is certainly an argument to be made to optimize soil conditions whenever possible.
A decent review:
http://cropsoil.psu.edu/sylvia/mycorrhiza.htm

I wouldn't mind reading the citations you are referring to Jim, can you provide them?
You are telling us but not backing it up.

BTW, If you drove someplace today - thank an engineer!!

John Quinn wrote:le.
A decent review:
http://cropsoil.psu.edu/sylvia/mycorrhiza.htm

Thanks for the link John. A nice article.

n container growth where we carefully control soil particle size, composition, added nutrients and moisture, the benefits of robust mycorrhizal growth may not be dramatic, but there is certainly an argument to be made to optimize soil conditions whenever possible.

That is, I believe, almost exactly what I said at the very beginning of this pointless foo fraw.

I gave chapter and verse (and I believe Nina did too) much earlier in the history of the IBC. I haven't kept the references and I'm too damned old and tired and cranky to want to go back and redo it.

Jim,
I disagree that this is pointless "foo fraw".

Rob & John are providing some interesting information that is valid and likely more helpful than a brief and dismissive comment implying a person w/ a legit question is wasting their time w/ something concerning their trees.

I certainly am not asking you to cite the sources but the point to be made is this:
This is a discussion that has probably brought good information to the group. I have learned from both of the links posted by John and Rob. Likely others have as well.

Neil

I wil give some arguments to Jim's side.

First, granted that mycorrhiza is without doubt beneficial to plant in soil, in a word because they vastly increase the root sphere that is the volume of soil from which a tree can retrieve water and mineral elements.
In a pot, volume of soil is limited from the beginning so the main advantage of mycorrhizes goes away. I had asked this question on Plant Health Care (which sells mycorrhizal inoculant) forum some years ago and got the answer that in most cases it is not significant. This answer has disappeared from their web site together with the forum but looking for Message-ID: <b8udn1$2v5$1@news.tiscali.fr> in google groups will give you a french translation.

On the experimental side, I have read dozen of abstracts on the subject retrived from http://mycorrhiza.ag.utk.edu/mterm.htm. Like someone stated, articles showing growth improvement by inoculating container grown plants do exist but most of the time the improvements are shown when at least one element (usually phosphorus) is restricted. When fertilization level is high, improvement is very reduced, not seen or even sometimes growth is impaired because of sugar consumption by fungus.
If someone has free access to mycorrhizal journal articles, I would be happy to read and discuss them.

Until someone is able to show me more data pertaining to container grown plants, I do agree with Jim that mycorrhizal benefits for container grown plants are at least vastly exaggerated because information obtained from earth grown plants is used as it is. There may be not benefit at all.