I have several palms that have gotten these grayish black spots on emerging spears (and other areas) and a black soot-like substance on the leaflets. Can someone tell me what this is and the best way to fix? I do have some systemic drench already in the garage...

scale.

 

 

 

Thanks for the good photos.  Scale.  Along with drench, it might not hurt to put used coffee grounds around the palms.

Thank you both! Will do on the Drench and coffee grounds.

It seems that type of scale is emerging this time of year. I've seen it on some of my palms. I just rub them off.

I've had good result spraying with horticultural oil, wait 24 hours, then blast off with a hose.

The oil smothers them, then 24 hours later they come off easily.

Also a good idea to treat the area for ants, as they can harvest them