I've been lurking on your forum for several weeks, having just started my first flock. I've been reading about the use of Diatomaceous Earth in a dustbox as a form of mite control. I just ran across this U of C study (published 3/28/2012) on Pubmed.com and thought it worthy of officially joining the forum so I could bring the info to you. I don't know if it has been peer reviewed or the number of chickens involved in the study. What I found most interesting was that while the DE and kaelon clay reducted parasites by at least 80% on dustbox user hens, while the sulfur product was effective even on non-dust box user hens after 2-4 weeks and, even after the dust boxes were removed, had a 9 week residual impact on all hens. Snag Med Vet Entomol. 2012 Mar 28. doi: 10.1111/j.1365-2915.2011.00997.x. [Epub ahead of print] Housing and dustbathing effects on northern fowl mites (Ornithonyssus sylviarum) and chickenbody lice (Menacanthus stramineus) on hens. Martin CD, Mullens BA. Source Department of Entomology, University of California Riverside, Riverside, CA, U.S.A. Abstract Hen housing (cage or cage-free) did not impact overall abundances of northern fowl mites, Ornithonyssus sylviarum (Canestrini & Fanzago) (Acari: Macronyssidae), or chicken body lice, Menacanthus stramineus (Nitzsch) (Phthiraptera: Menoponidae). Cage-free hens received a dustbox with sand plus diatomaceous earth (DE), kaolin clay or sulphur. Weekly use varied from none to 100% of hens; 73% of hens used the dustbox at least once. Ectoparasite populations on dustbathing hens (users) were compared with those on non-user cage-free and caged hens. All materials reduced ectoparasites on user hens by 80-100% after 1 week of dustbox use. Diatomaceous earth and kaolin failed to reduce ectoparasites on non-user hens, and ectoparasites on user hens recovered after dustbox removal. A sulphur dustbox eliminated mites from all hens (including non-users) within 2-4 weeks. Residual sulphur controlled mites until the end of the experiment (up to 9 weeks), even after the dustbox was removed. Louse populations on hens using the sulphur dustbox were reduced in 1-2 weeks. Residual sulphur effects were less evident in lice, but the use of a sulphur dustbox by a higher proportion of hens extended louse control to all hens. This is the first experimental study to show that bird dustbathing in naturally and widely available dust materials (particularly kaolin) can suppress ectoparasites and thus the behaviour is probably adaptive. 2012 The Authors. Medical and Veterinary Entomology 2012 The Royal Entomological Society.