What is the concentration ratio of this extract? For example, 20:1 or 4:1.

It's not that type of extract, this is a standardized form. Standardized extracts differ from the 20:1, 40:1, etc. extracts in that they dont use any specific amount of the herb to make the extract, instead they standardized the active bio-active ingredients to a certain %. In this case, this is standardized to 3% Rosavin and 1% Salidroside - so it honestly doesnt matter what amoutn of the herb was used to make it, because its a standardized extract..if you wanted something that is 20:1 or 4:1 or even 40:1, you will get a wider spectrum of the herb, if there are other active ingredients in the herb you are after. But with Rhodiola Rosea, its been scientifically tested and researched to have active ingredients such as rosavins, salidrosides - which is what this extract is standardized too and for. This is the Rhodiola Rosea extract you want here, 3% Rosavin and 1% Salidroside is whats used in all of the studies on this herb for stress management and energy.

Where was this product harvested?

package says the mountains of Tibet.

What is the tyrosol and rhodioloside content of this product?

Hi Wesley, each serving has 400 milligrams of Rhodiola Rosea (root) which is about 1/4 teaspoon, 3% is Rosavins & 1% is Salidrosides. (Info came from packaging). I hope that helps. If you need additional info, their phone # is 626-898-9198.