If I'm counting growth rings of a live branch that was cut in early June (here in Utah) I know that each prior year ring is usually easy to identify.

But in the sample I'm working on now, Mulberry, I'm thinking that the cambium is working on the 2020 growth ring and that as of early June it shows spring wood growth. And since I cut it in June, it will not produce any more wood with late wood being absent from my sample.

Am I correct in my theory that the wood on the inside of the cambium layer is for 2020? And the last full ring (light and dark) is for 2019?

I'm almost sure that would be the correct way to count the rings up through 2019 and into an incomplete ring for 2020.

I would just like some expert validation of this theory.

Thanks very much.

An annual growth ring generally consists of springwood and summerwood. These cells, otherwise known as secondary xylem, are produced to the inside of the vascular cambium layer. Cells produced immediately to the outside of the vascular cambium layer are referred to as secondary phloem.

As to your question, YES -- the wood immediately to the inside of the cambium layer is for the current growth year and the last discnerable annual growth ring is for 2019.

Check out this image: https://ib.bioninja.com.au/higher-level/topic-9-plant-biology/untitled-2/lateral-growth.html