We developed a reliable, inexpensive, and simple method for staining arbusc
ular-mycorrhizal fungal colonizations in root tissues. Apart from applicati
ons in research, this nontoxic, high-quality staining method also could be
of great utility in Leaching exercises. After adequate clearing with KOH, a
n ink-vinegar solution successfully stained all fungal structures, renderin
g them clearly visible.