Phoenix canariensis disease?

[Jason in SB CA]

My parents have two Phoenix canariensis that have been growing fine, but recently one of them has started to produce malformed fronds. Their gardener said it is a disease, but I am not sure if that is the case. I know they likely do not sanitize their tools in between trimming, so I would imagine all their canary island date palms would have this problem. If it is a disease, what can be done?

 

[Jason in SB CA]

For fun, here are some other palms I have growing there:

Ceroxylon alpinum
Roystonea borinquena (or oleracea, can't remember at the moment)
Rhopalostylis baueri
Dypsis decipiens
Parajubaea torallyi

and others

 

[kinzyjr]

31 minutes ago, Jason in SB CA said:

My parents have two Phoenix canariensis that have been growing fine, but recently one of them has started to produce malformed fronds. Their gardener said it is a disease, but I am not sure if that is the case. I know they likely do not sanitize their tools in between trimming, so I would imagine all their canary island date palms would have this problem. If it is a disease, what can be done?

Almost looks like frizzle top, but I haven't seen it on Phoenix canariensis.  If it is, fertilizing with manganese will help correct this issue. 

Might also be boron deficiency: https://edis.ifas.ufl.edu/pdffiles/EP/EP26400.pdf