Dead frond loss vs. frond retention.

[TomVaughan]

I have a question regarding the retention or shedding of fronds on Washingtonian palms.  I’m familiar with a grove of Washingtonian palms in which some of the trees have completely bare trunks while adjacent trees of approximately the same age have the trunks completely covered with fronds.  My question is what causes this phenomenon.

[Harry’s Palms]

Usually Washingtonia need to be trimmed to get rid of the old fronds to a “skirt” of dead fronds will form . The skirt is a fire hazard and a haven for rodents. I have mine trimmed once a year . Harry

[EdR]

I think it's partly climate related. In wetter and windier climates it seems 'skirts' are less likely to form.

Here are some in Kakamas in South Africa with full skirts, in the desert away from the coast and strong winds.

Around Cape Town the old leaves seem to get ripped off by the wind once the palm gets tall enough. It's typical to see the higher part of the trunk clean, but the lower part with persistent leaf bases. This one is typical, notice the old leaf bases are only now starting to decay and fall off on the bottom part of the trunk, they must be decades old (I remember this one was already fairly tall 35 years ago). 

[Jim in Los Altos]

It’s very much age related. I no longer need to have any of mine trimmed because they are self cleaning now. At roughly 25 years old is when they often start shedding their old fronds as well as old leaf bases. Top photo is nearly 100’ tall. Second photo is a younger one (just over 25 years old) that began shedding fronds on its own last year and old leaf bases are pealing back too. 
 

 

[Harry’s Palms]

Hmm , mine doesn’t shed , but then I don’t let them accumulate. Every Fall it has a few feet of skirt that I have trimmed off. Harry

This one ( left side of photo)is planted at the bottom of the hill, so it is very tall. It is about 30 years old. It requires trimming or a skirt forms and I am in a fire prone area. 

[Jim in Los Altos]

41 minutes ago, Harry’s Palms said:

Hmm , mine doesn’t shed , but then I don’t let them accumulate. Every Fall it has a few feet of skirt that I have trimmed off. Harry

This one ( left side of photo)is planted at the bottom of the hill, so it is very tall. It is about 30 years old. It requires trimming or a skirt forms and I am in a fire prone area. 

Your’s is really close to being a self shedder. Any time now. 

[Harry’s Palms]

Jim , that would be awesome . The first time a frond falls on its own will be celebration. I love the way they sway in the wind when they get this big . All that motion is bound to have an effect. Harry

 

[tim_brissy_13]

Agree with Jim. They start self shedding around 25 years old. One thing I’ve noticed and can be seen in above photos is that they’ll start from the top down. My theory is the expanded base of the trunk sort of locks the leaf bases tighter. They fall off easier once the trunk starts to thin out and grow upwards with uniform diameter.