The key to separating the two different forms would be to have the provenance or at least a solid reference to the same. That information would allow the assigning of a varietal name. Unfortunately, few people keep these records or have access to them.

These two forms should have their provenance available at a California botanical garden or herbarium. I have a salvia I got a long time ago from Smoth College that I called S. involucrata but probably is the pink bracted form of wagneriana. It shares a crimson band around the nodes with the white form. In both forms, the transition to the bracts from the adjacent leaves is not always sharp, and the leaves often have white sections and a vein structure intermediate between those of a normal leaf and those of the bracts.

The only other time I see this is when some sages decide to try to bloom in the spring, and a warm spell interferes, throwing the transformation into reverse, and generating some strange foliage.

I'm more familiar with salvias as a genus than other plant groups, but it would seem to me that salvias hybridize so easily that it's rather difficult to follow certain formats in a database. As in being familiar with coccinea 'tall form', or coccinea 'lavender form' or wagneriana 'white bract form'. I've seen wagneriana referred to as salvia wagneriana 'White Bract' as though it were a cultivar. This comes up because since Dave sold Dave's Garden and now has All Things Plants, we're creating a new database and I'd asked how they were going to handle the wagneriana "forms' issue ...likewise the other 'forms'. It seems that the salvias as a group seem to be quite often in a state of flux.
Thanks for your input.....

I just want to report that one of my S. wagneriana plants is about to bloom, and is close to 20 ft. tall! The literature states that it's ~ half that height. Though, I was told by someone who has seen it in its native habitat that the height I am seeing is typical. I think mine is so tall because it made its way through very tall and dense butterfly bushes and through a wood arbor in order to find the sun!

Hopefully posting the photo works...

What we really need is a registry, something akin to what the RHS does for orchids. Sadly, there is not the $$ in Salvias that there are in orchids, and financing this would be difficult.

Serious Salvia collectors should at least keep records of provenance, along with the names they were originally purchased under. Also the method of propagation, since varieties don't come true from seed.

Sherry:

I think the white bracted S. wagneriana is originally from U C Berkeley BG. I got it from them quite a long time ago. I have a S. involucrata from Smith College I'm pretty sure is the pink bracted form, but don't know where the pink form from California came from.

The simplest way to differentiate collected Salvia forms I know of is to use the name of the community it was collected from, like S. mexicana La Placita or S. puberula El Butano. These aren't good marketing names, though.

If someone like myself wants to change a name to reflect a convention, it is necessary to write up the old name with an explanation. That's one of the things I try to do with my records.

Richard, I agree with you that S. involucrata Smith College looks like a wagneriana. I took this photo of it last night [sorry the quality is so-so], placed next to the UCB white bracts S. wagneriana. The Smith College has reddish stems and petioles, like the more common dark wagneriana, but its inflourescence is much lighter [pink rather than magenta?]. The UCB white form has green petioles and stems. I will endeavor to take more photos as the flowers open.

Let me know if the foliage just under the inflorescence shows mottoled variegation and more of a gradual shift towards becoming bracts, with intermediate shapes and veination between foliage and bracts. This seems to happen with both wagneriana and the Smith College form if involucrata.

Both also have a maroon band around the stem at the nodes.

All this makes me suspect the Smith College plant is a wagneriana.