It's my understanding that E.pallida doesn't have the alkamides that E.angustifolia and E.purpurea have. Does the pallida have other constituents that the other 2 lack? Is there an instance where you would specifically want to use pallida over the other two? Thanks!

E. angustifolia has the highest levels of alkamides of the 3 Echinacea species you mention. In E. angustifolia they are found in the root, flower cone and seed. E. purpurea has little to no alkamides in the the roots, but has some in it’s flower cones. E. pallida contains other active constituents, but not alkamides. Alkamides are an important active constituent in Echinacea, but far from the only medicinally active phytochemical in the plant. I do not feel there are situations where I prefer E. pallida, I prefer E. angustifoila by itself,(it is by far the most active and effective species), or a combination of all 3 species. If you use E. purpurea, I suggest combining the root tincture with the flower cone tincture. That is about 65-70% as active as E. angustifolia in my opinion. E purpurea root by itself is much weaker.

Thank you so much for that detailed information! I should have asked this as part of my initial question...What about the activity of E.tennesseensis? I planted some last year because I like to grow endangered plants. Would that be a variety I could (eventually) harvest and use? Or better to stick to the others? Thank you for your time.

E. tenneesiensis has high levels of alkamides in the root and cone, I have used it and it works (not quite as strong as E. angustifolia, but much easier to grow).