Have you ever noticed a prickly pear cactus with white fuzz on it, especially around the thorns? That’s the tell-tale sign of the presence of cochineal scale bugs. And, while these little guys are unsightly, they hold a secret many people don’t know.
When cochineal are removed from the plant, dried, and crushed they produce a bright red powder which is a popular and safe red dye. Yes, that’s the truth! Some of the foods we eat contain crushed bugs. So does lipstick, and also yarns that are naturally dyed. In foods, just look for Natural Red Dye #4. It also might be named Carmine or Cochineal.
The process of getting dye from cochineal was first developed by the Aztecs. In the early 1500s, when the Spaniards saw the beautiful red color produced by this dye, they began importing it to Europe. It was a huge success. Many attempts were made to bring the cactus and the bugs to Europe to be grown locally. All attempts were met with disaster though; the weather just wasn’t right. So cochineal red dye continued to be imported until the mid-1800s when chemical dyes were developed from coal tar. Today commercial cochineal farming is a relatively small industry.
Adult male cochineal are winged, never eat and die shortly after fertilizing a female’s eggs. The females, meanwhile, insert their needle-like mouth parts directly into the prickly pear cactus and spend their whole lives drinking prickly pear juice and covering themselves in fluffy white, protective wax.
Suppose you have an infested cactus and don’t want to produce your own natural dye for your home spun yarn. You can reduce the damage from high populations of scale insects by applying systemic insecticide products, such as those containing dinotefuran or imidacloprid. Be careful to follow the directions when you use a new-to-you insecticide product. Spray only a part of a larger plant to make sure the insecticide is not toxic to the plant. Symptoms of toxicity include discoloration or burning on edges, tips of leaves and growing points. Thus far, there has been little research conducted on best practices for insecticide use on Texas landscape succulents and the Texas AgriLife Extension Service cannot ensure the effects or effectiveness of insecticide treatments.
by Kim Rainey, ECMG
For further information:
https://texascooppower.com/the-bugs-that-make-you-see-red/
https://citybugs.tamu.edu/2020/02/26/a-prickly-situation/
https://www.mentalfloss.com/article/648050/cochineal-insect-red-dye