Discerning Sabal palmetto vs. Sabal minor

[teddytn]

I’m sure this topic has been beat to death, for the old timers on PT I’m sorry. What are some visual cues people can use to I.D. confidently a juvenile palmetto vs. a quite older sabal minor? If you took a 3 gallon nursery pot size of these 2 it may be hard to tell apart, let alone if you found a mixed group in nature. 

[teddytn]

Even if leaves haven’t gone costapalmate yet on a palmetto the petioles should be longer than a minor. Haven’t seen a minor with filaments between the leaf segments either.

[NorCalWill]

If it's a quite older Sabal minor, then it may be blooming, in which case, the inflorescence will grow straight upward and are longer than the leaves.

I don't have Sabal palmetto, but my understanding is that the inflorescence aren't longer than the leaves.

 

[teddytn]

1 hour ago, NorCalWill said:

If it's a quite older Sabal minor, then it may be blooming, in which case, the inflorescence will grow straight upward and are longer than the leaves.

I don't have Sabal palmetto, but my understanding is that the inflorescence aren't longer than the leaves.

 

Sure sign is inflorescence definitely. I can’t see anyway a palmetto would flower when the size of a sabal minor. Even a very old sabal minor is the size of an immature palmetto. 

[teddytn]

http://w3.biosci.utexas.edu/prc/DigFlora/Waller/costapalmate.html#top
Maybe palm ID 101, but definitely helps to have pictures to refer to. 
In my opinion it’s still really hard to tell when plants are very young. Palmettos don’t always have a very extended costa at that point, and I’ve seen some sabal minors with a more extended costa than normal. Lines can get blurred until a little more mature.

[teddytn]

I have young Sabal minor and young Sabal palmetto both potted and planted to refer to. There’s 2 visual cues that are consistent through all the plants I’ve been observing. 

1. Sabal palmetto leaves/ petioles stay more upright, close to 45 degrees even when spent. Where Sabal minor leaves/ petioles hug the ground and lay more horizontal/ flat, close to 180 degrees ( not including the newest leaves of course ). @Allen has said before that palmettos “reach” upward, if you watch them grow when small that’s the best way to describe them.

2. Sabal palmetto when young holds its leaflets on a fan very tight and erect, “reaching” upward again. Where Sabal minor from the first fan leaf spreads it’s leaflets very wide, close to 180 degrees from leaflet to leaflet. 
 

These are all comparison shots of palmettos and minors of relatively the same age and size all roughy 3-5 gallon. Except the last pic.

Sabal palmetto below notice upright growth habit and leaflets close together and vertical.Palmetto same growth habitPalmetto same growth habitMessy double palmetto same growth habitPotted Palmetto same growth habitPotted Minor to match the last. Notice the change, all the leaves except the newest lay very flat.Minor with this layed down habit, notice the change in fan leaves, the leaflets spread out very wide to 180 degrees, with each leaflet not being very long making a wider rather than taller leaf.Minor same habit as aboveMinor same habit as above Minor same habit as aboveMinor same habit as aboveHeres some strap leaf plants to finish it off Sabal minor on the left Sabal palmetto on the right. Minor more layed down, palmetto more vertical