Could anyone shed any light on the relationship between actinorhizal plants and their relationship with the Frankia genus of bacteria that they interact with. Alders are probably the most well known species that fix nitrogen in this way and if you dig up an alder root you'll almost always find root nodules that are hosting the Frankia bacteria. But everything in the Elaeagnaceae family (which includes seaberries, goumi's, autumn olive, silverberry, etc.) also rely on this bacteria for nitrogen fixation. So my question is, do you need to innoculate your soil with Frankia bacteria in order to get the nitrogen fixing benefits of the Elaeagnaceae's or will they some how find it in the soil? I've had mixed results looking at root systems that are grown in a "sterile" medium. Also, would inoculating these plants with soil from underneath alders be effective in getting the Frankia bacteria to their roots?
Also, while Robert Kourik is here, could he provide some insight on the controversial role of nitrogen release from N2 fixing species, such as when is the best time to chop and drop, the different methods of N2 fixing for woody vs. herbaceous species, or any N-fixers that he finds particularly useful in terms of the fertility they release.
And while we have Mr. Kourik here, could he give his theory on the roots/understory of conifers, advice on growing underneath the crown of conifers, etc.
Thanks for visiting permies Robert!