Thrips

You may notice some flying bugs around your plants, see very tiny speck like translucent, yellow, brown, or black insects crawling on your columns with oblong bodies, mainly near tips in crevices between ribs. In advanced infestations you may see a tan colored uneven scarring, scabbing, corking, often starting at new growth and spreading downward. The cacti will later grow new green flesh up through this scab. Unlike fungal spots (which are often sunken, black/soft, or clearly circular), the damage looks superficial, textured like fine sandpaper, and is concentrated heavily at the crown of the plant. These are indicators you are dealing with the pests known as thrips - Thysanoptera. A great diagnostic tool is to place some yellow paper sticky traps near the columns. After you catch a few flying insects, inspect them closely compared to photos of adult flying stage thrips to confirm.

Understanding the thrip life cycle is critical for effective treatment.

• ** Egg:** 2-6 days. This insects eggs are laid directly into plant skin tissue, completely protecting them from insecticides and physical removal.
• ** Larvae/Nymphs:** 4-8 days. The very tiny young insects feed by sucking the plants juice on sections of new growth and hide in between ribs.
• ** Pre Pupae & Pupae:** 2-4 days. They stop eating, and drop down in or near the soil.
• ** Adult:** 2-4 weeks. Flying stage. Adults breed and females lay 50-300 additional eggs.

Warmer temperatures speed up the lifecycle timeline, cooler temperatures slow it down.

Thrips can be introduced into collections and gardens several ways.

• ** New Additions:** Introducing a new plant to the garden is the number one cause of sudden indoor or greenhouse outbreaks. Because females lay their eggs inside the plant tissue and pupae live in the soil, a newly acquired cactus or companion plant can look 100% clean under a magnifying glass but explode with larvae a week later.
• ** Infected Substrate:** If you use unsterilized outdoor soil, compost, or bulk organic materials in your potting mix, dormant pupae can be introduced right into the root zone of your pots.
• ** Outdoors:** Outside, thrips can come from nearby plants, weeds, soil, or even on the wind.

• ** Spinosad:**

[work in progress]