Since rainfall, humidity and bird populations, and bacteria n fungus, all play into the how, when and why these fatal wash fan frond bags'll slip down vertically, and crush the life out of the climber, unaware of their growth characteristics over that particular species' lifespan, here, in SoCal, where most of these tragedies occur.
Now my mentor and idol as a young teen climber in palms and hardwoods was Rich Magargal, a local climbing legend here in San Diego, recent recipient of the Bob Bichowsky Arborist Lifetime Achievent award, by The San Diego Professional Tree Care Association.
Just one of Magargal's areas of expertise is palms, date palms, fan palms, slicking dates, peeling fans, for decades, learning their anatomies, and particularly their growth characteristics over their lifespan, in SoCal.
The reason that info's so valuable to have and teach to others in the industry's?
Well it's because age and maturity of wash robusta's, that kill so many climbers here? Is the key indicator of a loose bag that's cocked n ready to slip vertically.
It's important to understand that when a wash fan's left alone by man? That same bag of fronds slips vertically, but only on fairly mature wash fans over the 35-40 plus feet point in their life. Younger trees with no asymmetrical variations in frond uniformity are quite dependably safe from any vertical slippage hazards.
The point I'm making rather clumsily here's that old pro's can recognize imminently dangerous wash fans about to slip, just by looking at their bag uniformity, combined with their age n height.
They stick out like sore dangerous thumbs, about to get hammered, to pros like Magargal, who's written and lectured at seminars, on this exact subject.
jomoco