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Robert Lee Riffle

WHAT IS A CROWNSHAFT?

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Robert Lee Riffle

I think one of the most misunderstood and misused terms in speaking/writing about palms is “crownshaft.”   Many folks do not seem to really understand just what it is and how to identify those species that exhibit one.

So, what IS it?

First of all it _IS_ a shaft---or column---which is found just above the trunk and just beneath the crown of leaves. It is usually green in color but may be a different color from that of the leaves themselves, including white, blue, red, brownish or orange.

Secondly, it is formed from the expanded bases of the leaves in the crown--i.e., it actually consists of parts of the living leaves (the BASES of the leaves) on the tree.  These leaf bases are wrapped tightly around each other to form the column or shaft.  The individual form of the leaf base components may be seen in a dead or dying leaf which is about to fall from the tree, the base becoming detached before its complete abscission.

The shaft is often bulging, especially at its base, a phenomenon caused by the leaf bases being of varying thicknesses.  Just as likely in nature is a shaft that is no wider than the trunk itself.

Some large genera (plural of “genus”) of palms have species with crownshafts and also species lacking shafts. These genera include Dypsis and Chamaedorea.

In some species of crownshafted palm the shaft is fairly indistinct because the leaf bases are not wrapped around each other very tightly, and the shaft becomes extended and “loose.”

Some crownshafted species do not form a shaft until past the juvenile stage (Dictyosperma).

NO PALMATE-LEAVED SPECIES FORMS A CROWNSHAFT.

SOME SPECIES THAT HAVE DISTINCT CROWNSHAFTS:

Adonidia

Archontophoenix

Areca

Carpentaria

Chambeyronia

Cyrtostachys

Hedyscepe

Kentiopsis

Normanbya

Pinanga

Ptychosperma

Rhopalostylis

Roystonea

Veitchia

Wodyetia

PINNATE-LEAVED GENERA THAT LACK A TRUE SHAFT:

Acrocomia

Aiphanes

Arenga

Astrocaryum

Attalea

Butia

Cocos

Elaeis

Jubaea

Jubaeopsis

Parajubaea

Ravenea

Syagrus

--------------

Coastal southeastern St. Lucie Co., Florida,

between White City and Port St. Lucie--zone 10a

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palmchap

Robert, is it possible for a palmate such as a sabal minor to have an underground crown shaft. I live in Arkansas and the sabal minors that grow in the swampy areas around mainly the Saline River seem to have some sort of shaft under the ground. I understand that if the above ground portion is frozen or destroyed the plant may come back later. Also it appears to me that there may be more subspecies of the Sabal minor here and I have talked to a biology and botantist about it. They are not convinced. What do I need to prove a new subspecies. Thanks.

I think one of the most misunderstood and misused terms in speaking/writing about palms is “crownshaft.”   Many folks do not seem to really understand just what it is and how to identify those species that exhibit one.

So, what IS it?

First of all it _IS_ a shaft---or column---which is found just above the trunk and just beneath the crown of leaves. It is usually green in color but may be a different color from that of the leaves themselves, including white, blue, red, brownish or orange.

Secondly, it is formed from the expanded bases of the leaves in the crown--i.e., it actually consists of parts of the living leaves (the BASES of the leaves) on the tree.  These leaf bases are wrapped tightly around each other to form the column or shaft.  The individual form of the leaf base components may be seen in a dead or dying leaf which is about to fall from the tree, the base becoming detached before its complete abscission.

The shaft is often bulging, especially at its base, a phenomenon caused by the leaf bases being of varying thicknesses.  Just as likely in nature is a shaft that is no wider than the trunk itself.

Some large genera (plural of “genus”) of palms have species with crownshafts and also species lacking shafts. These genera include Dypsis and Chamaedorea.

In some species of crownshafted palm the shaft is fairly indistinct because the leaf bases are not wrapped around each other very tightly, and the shaft becomes extended and “loose.”

Some crownshafted species do not form a shaft until past the juvenile stage (Dictyosperma).

NO PALMATE-LEAVED SPECIES FORMS A CROWNSHAFT.

SOME SPECIES THAT HAVE DISTINCT CROWNSHAFTS:

Adonidia

Archontophoenix

Areca

Carpentaria

Chambeyronia

Cyrtostachys

Hedyscepe

Kentiopsis

Normanbya

Pinanga

Ptychosperma

Rhopalostylis

Roystonea

Veitchia

Wodyetia

PINNATE-LEAVED GENERA THAT LACK A TRUE SHAFT:

Acrocomia

Aiphanes

Arenga

Astrocaryum

Attalea

Butia

Cocos

Elaeis

Jubaea

Jubaeopsis

Parajubaea

Ravenea

Syagrus

--------------

Coastal southeastern St. Lucie Co., Florida,

between White City and Port St. Lucie--zone 10a

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_Keith
Robert, is it possible for a palmate such as a sabal minor to have an underground crown shaft. I live in Arkansas and the sabal minors that grow in the swampy areas around mainly the Saline River seem to have some sort of shaft under the ground. I understand that if the above ground portion is frozen or destroyed the plant may come back later. Also it appears to me that there may be more subspecies of the Sabal minor here and I have talked to a biology and botantist about it. They are not convinced. What do I need to prove a new subspecies. Thanks.

Many of us truly wish that Robert would indeed answer your email as we miss him. He is no longer with us, except in memory.

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palmchap
Robert, is it possible for a palmate such as a sabal minor to have an underground crown shaft. I live in Arkansas and the sabal minors that grow in the swampy areas around mainly the Saline River seem to have some sort of shaft under the ground. I understand that if the above ground portion is frozen or destroyed the plant may come back later. Also it appears to me that there may be more subspecies of the Sabal minor here and I have talked to a biology and botantist about it. They are not convinced. What do I need to prove a new subspecies. Thanks.

Many of us truly wish that Robert would indeed answer your email as we miss him. He is no longer with us, except in memory.

I am so sorry, but I am new to this forum and the palm society. It stands to reason that I would try to carry on a conversation with a dead guy. How do I tell the live ones from the ones who are just memories?

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John in Andalucia
Robert, is it possible for a palmate such as a sabal minor to have an underground crown shaft. I live in Arkansas and the sabal minors that grow in the swampy areas around mainly the Saline River seem to have some sort of shaft under the ground. I understand that if the above ground portion is frozen or destroyed the plant may come back later. Also it appears to me that there may be more subspecies of the Sabal minor here and I have talked to a biology and botantist about it. They are not convinced. What do I need to prove a new subspecies. Thanks.

Many of us truly wish that Robert would indeed answer your email as we miss him. He is no longer with us, except in memory.

I am so sorry, but I am new to this forum and the palm society. It stands to reason that I would try to carry on a conversation with a dead guy. How do I tell the live ones from the ones who are just memories?

If you check out all the forums at least once, you will notice there is one titled, "Memorials". Top of the leader board for some time is, "Bob Riffle has passed away". These once active members still generate discussions to this day, hence the importance of the Memorials forum.

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bgl

Palmchap,

Actually, to see this thread revived came as a pleasant surprise! As you probably know by now, Robert Riffle passed away in Aug 2006. He was the Moderator of this Forum, and he was a very active and enthusiastic participant. Just to see Robert Riffle's name as the topic starter and his interesting avatar in an active thread almost makes one think he's still with us!

And presumably you saw what he posted above::

"NO PALMATE-LEAVED SPECIES FORMS A CROWNSHAFT. "

Bo-Göran

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palmchap
Palmchap,

Actually, to see this thread revived came as a pleasant surprise! As you probably know by now, Robert Riffle passed away in Aug 2006. He was the Moderator of this Forum, and he was a very active and enthusiastic participant. Just to see Robert Riffle's name as the topic starter and his interesting avatar in an active thread almost makes one think he's still with us!

And presumably you saw what he posted above::

"NO PALMATE-LEAVED SPECIES FORMS A CROWNSHAFT. "

Bo-Göran

Thank you for replying and yes I did see the information about the crownshaft. I can only hope that there are members as knowledgeable as Mr Riffle still in the society to assist novice palm enthusiasts

such as myself. Thanks again for replying.

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Howeadypsis

I never knew the man but since being a member of this forum I've come to realise his name is legend in the world of palms!

I think Robert's post above should be made a locked sticky at the top of this forum so all new members can read it-vital information!

Edited by Howeadypsis

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palmmermaid

I am glad this post came back up. I know what a crownshaft is. However, I did not know that no palmate species have crownshafts! Very interesting. And I think I will print of his list of pinnate genera and put it in the Encyclopedia for future reference.

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