Sabal palms and heels

[Chester B]

I know many of us believe Sabals develop heals after being in pots. This is where their long tap root hits the bottom of the pot and pushes back up. All of my Sabals with heels were purchased that way. Everyone I grew from seed and stuck in the ground or put in as a small seedling never developed a heel until now. 
 

Sabal uresana with heel that was developed one year after planting in the ground. Thoughts?

 

[Fusca]

It does vary among Sabal species - some think it's due to growing conditions.  I grew a Sabal guatemalensis from seed that stayed in a container for 5 years before I had a good place to plant it.  When I finally put it in the ground it barely had a visible heel started.  More recently I grew a Sabal Riverside from seed that only stayed in a container for a little over a year and had a bigger heel than the one pictured.  It's grown much faster than the guatemalensis so that probably has a lot to do with the difference in size of the heel.

[RJ]

Soil moisture perhaps?

[ExperimentalGrower]

Some recent Sabals I’ve come across here in NorCal all of which exhibit a significant heal.

 

[Joe NC]

http://w3.biosci.utexas.edu/prc/Sabal/saxophone.html

http://w3.biosci.utexas.edu/prc/Sabal/SAPA-5yr-sax.html

I bumbled across these links a few years ago, they helped me understand how and why the "heel" forms.