1.  Scales
The fronds are covered with brown crusty bumps or thick, white, waxy bumps or clusters of somewhat flattened yellow or whitish scaly bumps. The bumps can be scraped or picked off. Fronds may turn yellow and leaflets may drop. In some cases, a shiny, sticky substance coats the fronds. Scales are sometimes mistaken for reproductive spores produced by the fern. The round, flat, sometimes hairy spores are found only on the undersides of fronds, spaced at regular intervals. They are difficult to pick or scrape off.