Kaolin-based particle films

Definition

A pest management technology comprising finely ground kaolin clay particles suspended in water and sprayed onto plants or surfaces to form a uniform, reflective white coating. The film acts through multiple mechanisms: physical barrier to feeding and oviposition, irritant that promotes grooming and dispersal, reduction of host-plant recognition cues, and altered leaf microclimate that can suppress certain herbivores. Unlike conventional insecticides, kaolin films are non-toxic and leave no chemical residue, making them compatible with integrated pest management and organic production systems.

Etymology

From kaolin, a soft white clay derived from the Chinese hill name Gaoling (Kao-ling) where first mined; particle film, descriptive of the thin deposited layer of solid particles.

Example

In orchards, kaolin-based particle films such as Surround WP are sprayed to deter plum curculio (Conotrachelus nenuphar) and apple maggot (Rhagoletis pomonella) from recognizing and attacking fruit; the coating must be reapplied after rain.

Synonyms

• Particle film technology
• kaolin clay spray
• mineral particle film

Related Terms

• Integrated Pest Management
• physical control
• host-plant recognition
• oviposition deterrent
• organic pest control
• repellent
• insecticide resistance management

Usage Notes

Distinguished from horticultural oils and soaps by its particulate, non-phytotoxic mineral basis; effectiveness depends on complete coverage and frequent reapplication. The term specifically denotes the formulated product and deposited film, not raw kaolin powder. Some formulations include additional minerals or adjuvants to improve rainfastness. Research extends to veterinary applications (livestock fly repellency) and stored-product protection.