What Causes Cycads to have multi heads?

[Collectorpalms]

Hi, always wondered why some sagos ( and etc..)end up multi heads. What causes this?

[Tracy]

Some cycads species are  more prone to having second or multiple growing points than others that emerge on the caudex above the ground.  With some, this occurs after a trauma, others will develop a new growth point where cones have emerged.  I have seen some Zamia's that do it somewhat independent of coning or trauma near the flushing point.  A different way of looking at it is why do some never develop a second growth point, which when one includes basal subterranean suckers as part of the "second growth point" group, would mean a minority of cycads don't develop some form of secondary growth points.

Since basal subterranean new growths develop roots, they are often easier to harvest and grow as a new plant.  If you develop a growth point above the soil, you often have two choices, try to remove it, which will leave a nice scar on your caudex or let it grow and have multi heads.

[Collectorpalms]

Was distracted my the three heads., that I Didn’t notice it was growing out of a rock. 
this may have been pups that developed higher up?

Edited April 5, 2021 by Collectorpalms

[Tracy]

6 hours ago, Collectorpalms said:

this may have been pups that developed higher up?

I don't know if they are considered "pups" if they are growing off the main caudex higher up, yes.  Since that Cycas needs to have something to put roots into, I presume there is a hole in that rock that it was planted in, giving it this appearance of growing on the rock.  This is an example of a Cycad (Encephalartos arenarius x woodii) that pushed out flushes where it had previously coned.  the branching to the right used to be on the top of the cycad, and there is another branch on the backside, not visible where another cone had emerged with this one.  The entire plant leans to the left due to a large basal pup which was pushing the main caudex sideways.  The large basal pup was removed to go to a new home a while back but the result of its pushing didn't change.  In this case it was quite apparent what was happening about a year after the cones died and there remained large bumps where the cones had emerged from under the fuzz.

[Tracy]

One more interesting example.  I have had this Encephalartos inopunus since it was about a 1 1/2" seedling.  It pushed out a basal pup shortly after I acquired it.  That pup is the largest of many now.  The main caudex has actually been lifted up because so many basal pups emerged from underneath it that it appears like a bubble on top of all the sideways pointing pups.  Why did this plant grow like this instead of one main caudex and wait until much later to start producing offsets?  No answer on my part, its just part of the normal distribution of characteristics, perhaps toward the tails of the bell curve, but still not unheard of.

[Tracy]

22 hours ago, Tracy said:

Encephalartos inopunus

Yes... I can sPill or sPelL.  Encephalartos inopinus.

[Merlyn]

I've read that trauma can cause multiple heads on a normally solitary species.  There is a Lepidozamia Peroffskyana at Leu Gardens with 4 growing points.  I'm guessing something fell on it, since all the growing points are at the same height.  I have a photo somewhere.  

Someone on the FB Cycads group said that they forced head splits by cutting off the cone of a cycad.  They cut down vertically with a sharp knife (like a machete, I guess) just far enough to damage the growing point without killing it.  When the cut healed it split apart.  I have a bunch of random Revoluta pups in pots, maybe I will try it.  I'd imagine it may work...or maybe not!

[Merlyn]

Here's that Peroffskyana.  It is just East of the main group of cycads, and should turn into a beast of a specimen.  The 4 growing points all appear to be about the same height, which makes me think something fell on it and caused the split.  Maybe @Eric in Orlando knows what happened to this one?

[Eric in Orlando]

On 4/7/2021 at 12:37 PM, Merlyn said:

Here's that Peroffskyana.  It is just East of the main group of cycads, and should turn into a beast of a specimen.  The 4 growing points all appear to be about the same height, which makes me think something fell on it and caused the split.  Maybe @Eric in Orlando knows what happened to this one?

 

That happened over 10 years ago and it hasn't grown much since. Not sure what caused it, nothing fell on it.

We have had a couple Cycas revoluta crest in the past. They grew for a couple of years then just up and died.

 

[tropicbreeze]

Cycas armstrongii with a severe case of multiple personality disorder.

[Collectorpalms]

That’s fun!