MandB
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mycorrhizae additive?

Hi there,

I work part time at a nursery and one of the products that it has been encouraging is a product called Mykos, which is basically mycorrhizal spores which people are instructed to sprinkle under the roots of plants when they transplant, or to incorporate into their soil. I recently did some research on mycorrhizae and am very fascinated by it. I have come to the simple conclusions that:

1) Mycorrhizae is good (almost always, though in some cases like commercial corn production, it has the potential hurt the plant)
2) Mycorrhizae is already naturally occurring provided that the environment is right for it (ex. we don't till too much or use soilless or sterile potting mixtures)

The things I am less certain about are whether or not I would want to add mycorrhizae to my garden. I am very interested in using it with my vegetables, and I also have some ailing fruit trees, who I think could be helped by more mycorrhizae. So far, the two best articles I have read about mycorrhizae have contradicting conclusions about adding it.

https://www.fungi.com/blog/items/mycorrh ... ement.html

Promoting adding mycorrhizae, Amaranthus writes:
There are practical solutions to some of the mycorrhizal deficiencies in man-made environments and reintroducing mycorrhizal fungi in areas where they have been depleted can dramatically improve plant establishment and growth.
Then there is this article by Chalker-Scott, https://puyallup.wsu.edu/~Linda%20Chalke ... rhizae.pdf . She writes:
scientific studies on urban landscapes and other “real world” systems report that these products have no significant value. In general, plant species inoculated with commercial products and installed into the landscape are equal in performance to uninoculated controls (which quickly became colonized with native fungi). While the addition of organic matter has been found to stimulate growth of native mycorrhizal populations, applying commercial mycorrhizal amendments is generally ineffective and unnecessary, given the widespread presence of indigenous inoculum.
Perhaps they are not as contradictory because the first is saying that adding micorrhizae is good for plants that have been depleted and the second is emphasizing that plants in "real world" situations will not necessarily be depleted.

So my question is if anyone has used straight micorrhizae before? And what are people's thoughts about doing this? I know people have spoken about using fertilizers with micorrhizae and I have loved the discussion here about micorrhizae in general: https://www.helpfulgardener.com/forum/vi ... p?p=153450. However I still don't know what to think about adding it. I also want to know if I add it to my soil, whether I need to add more fertilizers because the plants will be accessing the nutrients in the soil more effectively?

I look forward to hearing your insights!

imafan26
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Re: mycorrhizae additive?

There are all kinds of microorganisms in a healthy living soil. The ecosystem that supports the soil web lies above and below ground. Different soil types, environments will support different kinds of organisms.

Mycrorhyzzae are just one group of organisms living in the soil.

The most important function of the microrhyzzae that I know of is the part that they play in the nitrogen cycle. Microrhyzzae are naturally found in the soil, but they may not be the dominent species in the soil. If you have a lot of them then you don't really need to add more. Some species of microrhyzzae are especially good at forming symbiotic associations with legumes. They need to be present around the root zone of the legume as they don't move around much or have a way to sniff out a root very well. When they come in contact with the legume root, they infest it and form nodules, they actually will take nutrients that the plant makes through photosynthesis but in return the microrhyzzae is able to convert atmospheric nitrogen to nitrogen that the microrhizzae and the plant can use. When the plants are tilled in, not eaten or pulled out and discarded somewhere else, the nitrogen stored in the plant and microbe tissues will be released to the soil.

If you are growing a green manure as a cover crop, nitrification is enhanced by using an inoculant for the cover crop. That means the seeds are coated with the microrhyzzae to increase the number of nitrogen fixing nodules that form on the cover crop roots. There are different inoculants available that are bred for specific cover crops. Cowpeas, sunhemp, hairy vetch, and soybeans are common nitrogen fixing cover crops that are inoculated to increase their efffectiveness.

Sterile potting media is sterile, so does not have a microbial community present at the outset. It does have advantages since it also will not have any bad stuff like root knot nematodes or bacteria that causes phythoptora either. Adding microrhyzzae to a potted plant is a very small ecosystem. Over time other bacteria and fungi will migrate into the pots but in the beginning I don't know how much help they will be, at first they only have each other to eat and if the microrhyzzae are not kept at an optimal temperature, and they don't have other food to sustain them they die. Sterile potting media does not contain any nutrients unless it is added. Seeds provide nutrients for the seedlings for the first few weeks, but will need to be supplemented after that. Microrhyzzae form associations with legumes. If you aren't planting a legume, how do they live? Dead microrhyzzae probably don't do a lot.

BTW, it can sometimes be a pain to inoculate seed. First depending on where you live, it might be hard to find inoculants locally. If like me you live in a state where it is hard to get anything live brought in, it can be really hard to get as you have to find a company willing to ship it. The inoculant I get for cowpeas, it is easy to get cowpea seeds, (not so easy to get sun hemp), first needs to be coated in molasses and then the inoculant and then dried in the shade and planted within 4 hours. The good thing is that the inoculant is usually good for a year stored in the refrigerator and there is usually more than enough inoculant for my small plot. To get the benefit, the cover crop needs to be tilled under as it starts to flower and it will benefit the following planting after it has time to decay and release the nitrogen.

If you let the cowpeas form pods and eat the pods, then the nitrogen transfers from the plant to the pods, and when the pods are removed, the nitrogen in those pods do not get returned to the soil. Flowering is the time of peak nitrogen fixation.

https://soils.usda.gov/sqi/concepts/soil ... d_web.html
https://www.uvm.edu/vtvegandberry/factsh ... crops.html
Happy gardening in Hawaii. Gardens are where people grow.

Juliuskitty
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Re: mycorrhizae additive?

I plant in containers using Promix BX, basically peat, perlite and vermiculite, but it has added Mycos ( and other things). Another website I frequent has a great deal of proponents of Actinovate (mycorrhizae source) because of the nutrient fixation help, and it is organic. So I add a root dip to my container plant outs. Most think, no harm here, and it can help.
BTW, they also use the Actinovate as a foliar spray fungicide. I don't find it effective for that, tried it, went back to dilute copper spray which works greatly on my Septoria plague. I grow mostly tomatoes.
My definition of insanity; trying to grow heirloom tomatoes in South Florida!

imafan26
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Re: mycorrhizae additive?

Is the microrrhyzae providing enough nutrients for the tomatoes or do you still have to fertilize with something like fish emulsion?

It would be an interesting experiment to try one day using peat lite with microrrhyzae vs peat lite with slow release fertilizer and no other fertilization and see what happens. Peat lite by itself without additional nutrients I already know provides good root support, but provides next to nothing in nutrients.
Happy gardening in Hawaii. Gardens are where people grow.

Juliuskitty
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Re: mycorrhizae additive?

You still need to provide nutrients if none were present before. These fungi colonize the roots and help fix nitrogen to the roots and also themselves, but if not much is present it wont make any on its own. At least that is my understanding.
My definition of insanity; trying to grow heirloom tomatoes in South Florida!

imafan26
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Re: mycorrhizae additive?

I thought rhizobium only fixes nitrogen on legumes and other nitrogen fixers like ironwoods. But thanks to you I've learned they do much more than that.

I did a bit more research and found a couple of articles that said that rhizobium can benefit many plants by invading the plant rhizosphere and make nutrients especially phosphorus more available to the plants.

Many different types of soil organisms living in the soil in concert create a balance in the soil. In the soil it really does take a village to make the system work. It also explained why plants are so environmentally sensitive to temperature, pH, water, etc. The soil biota are not very active at low temperatures and the dominant species changes with temperature, pH, aeration.

At the garden I volunteer at we mix our own soil mix and steam sterilize reclaimed media. One of the volunteers always tosses in a couple of shovels full of dirt/soil into the mix. It makes sense now, the amount of dirt that is added is too small to affect the function of the soil mix but those shovels of dirt would contain a whole village of soil microbes to recolonize the sterilized soil mix.

https://www.extension.umn.edu/distributi ... 03_02.html
https://www.bashanfoundation.org/hani/haninonlegumes.pdf
Happy gardening in Hawaii. Gardens are where people grow.

Artemesia
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Re: mycorrhizae additive?

Mycorrhizae are not nitrogen fixers. They mainly dissolve phosphorus with acids into a form that plants can absorb. The plants in turn help feed the mycorrhizae with carbohydrates. Mycorrhizae are fungus. Most nitrogen fixers are bacteria such as rhizobia.

There are several different types of mycorrhizae. Some float freely in the air and some are only transported by contact with insects, mammals, birds, etc. Some form close relationships with plants and some merely cling to plants. Some are stimulated by nothing more than root exudates in close proximity to them. Most can survive in a saprophytic state on organic matter until the right roots come along. Most plants need mycorrhizae very much but some only need them a little and some hardly need them at all.

If soil has been recently bulldozed, there may be very little if any mycorrhizae. In those cases it is useful to inoculate. You can make you own with soil and roots in the area. Some companies that sell mycorrhizae have done an incredible job and they have managed to isolate strains that are unbelievably effective. Unfortunately, all the research I have read indicates that these foreign strains are almost always overwhelmed by the native strains within just a few years. Chemical fertilizer tends to reduce mycorrhizae populations.

You can only experiment with each brand to know if the payback is worth the expense. I do not usually bother because faster growth usually means fewer nutrients. I want more nutrients, not less. But in some situations I am sure it is good.

MandB
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Re: mycorrhizae additive?

Thank you everyone for your replies! This gives me a lot to think about. Artemesia, I looked at the website in your signature and found another very helpful article about Mycorrhizae with some additional links: https://www.gardenfornutrition.org/Benef ... _Soil.html (for others who are interested).

Brimming with curiosity, I just ordered and read Mycelium running by Paul Stamets which has given me A LOT more context. I also looked at a few of the products sold at our nursery, and have some more information to help me and others out.

First of all, it is good to point out the difference between mycorrhizae and rhizobium (which is a bacteria). As Artemesia pointed out, mycorrhizae does much more than fix nitrogen, it enhances phosphorus and other micronutrient absorption. Not only that, but when different plants are connected through a web of mycorrhizae, the fungus can actually transfer nutrients form one plant to a more depleted plant. It is sort of like a huge network that optimizes the use of the nutrients in the soil. This not only helps plats absorb nitrogen, but helps them retain moisture, get other nutrients, and increase its immunity against other diseases and environmental stresses. Mycorrhizae was much more common in soils in the past, but now are less prevalent because most nurseries sell their plants in sterile fungus-free soils, and processes like tilling and bulldozing damage (or kill) it.

From my research, I think that I will introduce some mycorrhizae into my soils since I have inherited a bunch of plants from the nursery (plants they were going to throw out), and I also recently tilled some rock-hard and rocky clay soil in my back yard to start a vegetable bed.

This is what I have found out about the products that are for sale

*The brand, Mykos, that I mentioned earlier, has the spores of only one kind of mycorrhizae in it, "glomus intradices." Glomus intradices is an endo mycorrhizae, and it looks like it pairs best with vegetables like tomatoes, onions, flax, and cowpeas (according to wikipedia). However, perhaps it is fine with others as well...

*A nice surprise is that the brand EB Stone incorporates a lot of beneficial fungi in almost all its mixes. In its Smart Start mix, which I have, there are the following Endo mycorrhizae: glomus intradices (same as Mykos), glomus mosseae, and glomus aggregatum. I haven't looked any besides glomus intradices, so I might have more on these strains later. For Ecto, they have: mycorrhizae pisolithus tinctorius, rhizopogon villosuli, rhizopogon luteolus, rhizopogon amylpogon, and rhyzopogon fulvigelba The main point is that it looks like if any of you use EB Stone products, you are already on your way to introducing beneficial fungi to your yard. They also include two fungicidal fungi: trichoderma harzianum, and trichoderma viride.

*https://www.mycorrhizae.com/ is a very hard to navigate website, but it run by Dr. Amaranthus, who authored one of the articles I posted earlier. His products are used in the EB stone mix as well as Dr. Earth, and a bunch of other companies'. I also hear the rumor that Monrovia nursery, and even Stamet's company (listed next) uses his mycorrhizae. That was only listed on another forum though and I have not found anything to back up the rumors. If I could find more information on how to buy his things, I would have a better idea if I want it or not.

*I am most interested in buying from fungi.com (Stamet's company) because after reading his book, I feel like I trust him the most. That is perhaps more of an emotional reason, but at least I admit it. Also his mycorrhizae is available in multiple forms, and combinations. The mix just for vegetables only contains endo mycorrhizae. On other forums, people have complained that his mixture is unnecessarily expensive, though, so I do have some hesitations.

Some information on plant pairing with endo and ecto mycorrhizae

This link shows whether plants pair better with endo or ecto mycorrhizae
https://www.mycorrhizae.com/wp-content/u ... alpdf1.pdf

Many people say that brassicas do not pair well with mycorrhizae, though there is also research that it could encourage the growth of ecto mycorrhizae. A really cool thing I learned in Stamet's book is that if you grow elm oyster mushrooms (Hypsizygus ulmarius) with brassicas, they will increase the yield! I can't wait to start growing the elm oyster mushrooms! I think that will be my next project.

I still feel a bit lost, but it seems that all my plants pair best with endo mycorrhizae except for my lime tree, which does better with ecto.

Artemesia also mentioned the high possibility that eventually the added mycorrhizae will be overwhelmed by other local fungus. I can definitely see that, and would ultimately not have to depend on adding this to my garden. Other slower ways of encouraging mycorrhizae into the soil is to grow mycorrhizae-loving cover crops. I have a patch of peas and oats in one small spot of the garden, and will be planting a patch of fava beans as well sometime soon. Hopefully that will add to a positive growing environment.

Lastly in terms of nutrients in the soil, my thought is that the mycorrhizae will optimize the use of nutrients already in the soil, so at least according to Stamets, the presence of mycorrhizae would lessen the need for fertilizers. That said, I don't think it would be fair to grow plants only in peat lite as there would be hardly any nutrition for the mycorrhizae to optimize.

I feel like I went a little fungus-crazy. This is also my first time posting on this forum (including my initial post in this thread) so hello!

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applestar
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Re: mycorrhizae additive?

:clap: WOW! Thank you so much for posting what you've been learning! :clap:

This is a subject that I had some interest in due to Stamet's book you mentioned and after the book study we did on Teaming with Microbes, but I had other pressing interests recently and my mind wasn't tuned into studying more about it right now. So it's greatly appreciated that you've done the homework and given us a head start with "cliff notes" :wink:

Now, I'm going to out this subject back on my study list and get my mind wrapped around the concept! :D
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imafan26
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Re: mycorrhizae additive?

Thank you all for all your research, I've learned quite a lot in this discussion. I have used rhizobium inoculants on cowpeas to improve nitrogen fixation. The soil I have is very poor. Without inocultion the root nodules number 0-4 small nodules, essentially none. After inoculation, root nodules go up to about 8-12 small nodules. But even double cropping again with cowpeas, if the second crop is not inoculated the nodules go back to 0-4 again so the soil has not been able to retain or sustain the rhizobium numbers even in the short term. I suspect they do not like the pH 7.8 and sodden soil conditions.

Microrrhyzae help the plant utilize nutrients in the soil better, improve plant health and resistance to stress, increased root growth and plant vigor, reduced fertilizer and water requirements, and helpful in phytoremediation of of petroleum and heavy metal sites.

https://aggie-horticulture.tamu.edu/facu ... hizae.html
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