What’s going on with my Sago?

[Jayme J]

It’s been this way since I bought this house 4 years ago.  Though, it seems to be getting worse.  Is it manganese deficiency?  Doesn’t quite look like what I can google.  South Florida here.  Soil is mostly sand

[Merlyn]

@Jayme J did the new fronds grow out with the random brown spots, did they develop just as the flush was "hardening off," or did they turn brown later?  Manganese deficiency shows up during or near the end of the new flush.  One possibility is hail damage, since it is so random.  It is not Magnesium, as that would show up as yellow tips on the oldest leaves.  I would also check for CAS (Cycas Aulacaspsis Scale) on the underside of the fronds.  I don't see any in the picture, but sometimes they only infest the bottom side at first.

[Jayme J]

They came in normally and slowly became this way. I had an arborist out.  It's a pretty nasty scale infestation.  Also on the larger oil palm above this.  They are currently treating. 

 

[Merlyn]

@Jayme J yeah if it were a Manganese deficiency aka "Sago frizzle top" you would see the fronds grow out normally and then turn brown right about the time the new flush is hardening off.  I'd give it a handful of Manganese Sulfate anyway, as they have a tendency to get deficiencies in sandy FL soil. 

Hail or scale damage typically takes a couple of months before it really affects the leaf appearance.  So if it slowly showed up over a period of time then scale is a good bet.  Mealybugs can be treated with oils, soaps, and various insecticides.  If it's CAS (Cycas Aulacaspis Scale) then a 3 step solution works:

• Wash all the adults off with a regular hose sprayer on a "jet" or higher pressure setting.  Any adults have a hard armored shell and are immobile, so then they die without laying more eggs.  Pay special attention to the underside where they like to hide.
• Spray the fronds and center growth point with your favorite insecticide, such as Acephate, Malathion, or similar organophosphate.  This kills the hatched babies.
• Soil drench with Dinofefuran at label rates.  Other systemics (like Imadicloprid) are known to not work against CAS.

I drink a lot of espresso, so I toss my old grounds near the base of my ~75 Cycas species.  I did an experiment a few years ago with a bunch of small Revoluta.  Coffee grounds definitely helped reduce scale infestations, but wasn't really a "cure."  Neem oil is suggested for scale, but all I've managed to do with it is burn the leaves in the sun...with no effect on the scale.

 

[TropicsEnjoyer]

Neem is overrated imo. Other things do the same job and usually do it better.