In past newsletters, I've described how mycorrhizal fungi add a certain "intelligence" to the root zone. This beneficial fungi colonizes the surrounding soil to bring nutrients and moisture to their host plants, guards roots against pathogens, and fluffs up heavy clay to admit oxygen.
However, there is another aspect to these complex organisms that is worth exploring; the movement of nutrients not only from the soil to host plants, but also between plants.
A few quotes:
1. From The Growing EDGE magazine: "...fungal mats connect plants of different species, transferring substances produced by one plant to other, possibly even unrelated, species. Dr. Robert Griffiths at Oregon State University in Corvallis reports that in seedling trees in the midst of established stands, as much as 30% of the photsynthates (compounds produced by the plants through photosynthesis) could be traced to other mature trees in the area. That means the young trees are getting as much as a third of their nutrition from older, established trees."
2. From Agricultural Research magazine, describing formal USDA trials: "Agricultural Department scientists have found that growing tomatoes in a living mulch (hairy vetch) increased yield by about 138 percent and reduced insect infestation so much that it was hardly a problem. ...an added bonus was no tillage and less fertilizer, herbicides and pesticides. ...plants grown under the vetch mulch averaged a yield of more than 45 tons per acre, trailed by 35 tons for plastic mulch and 34 tons for paper. Plots with no mulch averaged 19 tons per acre."
3. From the book, Let Nature Do The Growing, The Fertilizer-free Vegetable Garden, by Gajin Tokuno (translated from Japanese): "In short, instead of regarding them with hostility, it is wiser to realize that weeds loosen the soil and provide important nutrition and to allow them to grow together with vegetables in a natural ecological system."
4. Again from The Growing Edge: "Fruit trees found growing in forests often have less overall disease and insect infestation than similar ones in cultivation. When starts of what seemed to be an exceptional tree found in a forest were taken into cultivation, they tended to vary from their performance in the wild. Cultivation enhanced vigor and productivity, but qualities such as flavor and disease-resistance often decreased or at least changed. It seems likely from the discoveries with mycorrhizal fungi that the tree in the forest could have been receiving substances from other palnts that increased its health and perhaps even entered into the quality of its fruit."
What a wealth of potential agricultural research topics! The USDA scientists conducting the living mulch experiment were unable to explain why the companion vetch produced such huge benefits to the tomatoes, but after working with mycorrhizal fungi for years, the answer seems pretty obvious to me.
I'm particularly fascinated by the potential effects on flavor by these nutrient transfers and I would think that wine grape growers in particular might want to carefully consider which cover crops to strategically plant between their rows. Other growers and crop advisors should note the effects on yields and the non-chemical disease resistance.
The reduced insect damage is consistent with our company's own observations, as noted in my previous newsletter (see further Newsletter Archives).
I incorporate this nutrient-transfer information into my own vegetable garden by seeding narrow rows of Crimson Clover next to my tomatoes, inoculating both the clover seeds and the tomato transplants with mycorrhizal fungi spores. I cut the annual-type clover off at the soil line after it blooms but before they go to seed, and get exceptional yields of wonderfully flavored tomatoes with only tiny amounts of dry organic fertilizer and some volcanic trace minerals scratched into the topsoil before planting.
For those who want to try this low-input biological approach, I recommend our MycoMinerals product. Just note that the method will NOT work as well if you use high-analysis NPK fertilizer or apply added fertilizer (especially liquids) during the growing season. Those artificial "plant foods" disrupt the biological processes.
Mmmmmm, I can almost taste those sun-ripened 'maters now!
Good growing, my friends,
Don Chapman
President, BioOrganics, Inc.