We have several dozen queen palms (Arecastrum romanzoffianum) that are showing significant decay around entire circumference of lower (from grade level to 3-4 feet) trunks. Trees are planted in turf and get broadcast irrigation. Decay is primarily within area of trees that are subject to this irrigation.

We suspect pink rot, but cannot confirm. How can pink rot in queen palms be positively identified? (Pink Mycelia not obvious.) If this is pink rot, is there anything that could be done to preserve the impacted trees?

If this is not pink rot, what is it? How could trees be treated?