Aulacaspis yasumatsui (cycad aulacaspis scale (CAS)) or the Asian cycad scale, is highly damaging to cycads, which include horticulturally important and endangered plant species. The cycad scale is an unusually difficult scale insect to control, forming dense populations and spreading rapidly, with few natural enemies in most localities where it has been introduced. The scale has the potential to spread to new areas via plant movement in the horticulture trade.