<human>:  Would an oil painter avoid reds from scale insects that live on a cactus?
<bot>: Yes, an oil painter would avoid reds from scale insects that live on a cactus. Carmine is the product of an insect that lives on some cacti. Carmine is not stable in oil paints and its usage has been discontinued. So an oil painter would avoid reds from scale insects that live on a cactus. So an oil painter would avoid reds.