The neck or rhizome is actually an ‘underground stem’, made up of the ‘bud scale scars’ left each year after the yellow top dies back in the fall.
The neck is sometimes referred to as ‘the twirl’ because the scars are always 90 degrees opposite from the previous scar, giving it an interesting ‘spiral’ pattern.
The bud is located at the very top of the neck, and will eventually be the part of the plant you see above ground during the growing season.
The scars are also referred to as ‘bud scale scars’. Each one is where the plant grows it’s top and dies back at the end of the season. A single ‘bud scar’ is produced every fall after the yellow plant stem falls to the ground, so for each year the plant produces a top, there is a scar left on the rhizome.
The root collar is where the neck meets the main root. If counting from bottom to top, This should count as year one, when counting the bud scars. Depending on how many bulbs extend from one neck, there may be more than one root collar.
The main root is considered a ‘fleshy taproot’ and operates as the nutrient storage & absorption organ for the ginseng plant. This is the most valued part of the plant for medicinal purposes.
The tail roots & fiber roots are the small roots that branch out from the main root. These serve as support, moisture & feeding roots, and help the entire plant function in it’s often harsh environment.