of Publication30th Year Volume XXX, Number 1/2, January/February 2008 Orange Oil for Drywood Termites: Magic or Marketing Madness? By Bill Mashek and Photo courtesy USDA William Quarles here is a thriving market for reduced-risk pesticides. Many T pesticides containing conven- tional active ingredients such as chlorpyrifos and diazinon have been phased out of urban markets. Their widespread use in both agriculture and urban areas had led to increased exposures and unacceptable risks (FQPA 1996; NRC 1993; Wright et al. 1994). They were also a threat to water quality in many areas (Johnson 2004). A rich source of new pesticides is plant essential oils. Some of these occur in food and are even exempt- ed from pesticide registration by the EPA. Active ingredients in the new products include oils of clove, rose- mary, mint, and oranges. Large cor- Termites like these are vulnerable to desiccation. Contact with orange oil porations such as EcoSmart, Woodstream, and Whitmire have kills termites by damaging their exoskeleton, causing loss of water and made these pesticides readily avail- protein. able (Quarles 1999a; Isman 2006) to present what is currently known Orange oil is an oily mixture (see Resources). about orange oil for termite control extracted from orange peels, and Orange oil has attracted a lot of so that possible customers will have the major components are chemi- media interest because it is a natu- better information to evaluate the cals called terpenes or terpenoids. It ral product and has low toxicity to treatment. For comparison, we will is a volatile liquid and has a strong mammals. It is a by-product of summarize some of the other meth- odor of oranges. A chemical relative orange juice processing, and is ods used in California for drywood of orange oil is turpentine. Both extracted from orange peels. Orange termite control. food grade and technical grade oil is currently available as an insecticide (Orange Guard™; orange oil are available. According ProCitra®) and as an herbicide What is Orange Oil? to Jeff Chang of Florida Chemical, a (Green Match™) (see Resources). It Orange oil should not be confused major supplier of orange oil, there has been registered in California with orange juice. Orange juice is In This Issue under the brandname XT-2000™ basically a water extract; orange oil for control of drywood termites. If is insoluble in water. Though all the claims are true, it is the holy orange oil has low toxicity, it is irri- Orange Oil 1 grail of pest control—an effective tating to eyes and skin, and drink- ESA 10 natural product with low toxicity ing it would cause vomiting. Calendar 15 and no toxic residuals; a green Repeated exposure could cause Books 16 product obtained by utilization of allergic sensitivity in some individu- Ask the Expert 17 waste. The purpose of this article is als (MSDS 2006). Update Schematic courtesy Florida Chemical Company The IPM Practitioner is published six times per year by the Bio-Integral Resource Center (BIRC), a non-profit corporation undertaking research and education in inte- grated pest management. Managing Editor William Quarles Contributing Editors Sheila Daar Tanya Drlik Laurie Swiadon Editor-at-Large Joel Grossman Business Manager Jennifer Bates Artist Diane Kuhn For media kits or other advertising informa- tion, contact Bill Quarles at 510/524-2567, [email protected]. Advisory Board George Bird, Michigan State Univ.; Sterling Bunnell, M.D., Berkeley, CA ; Momei Chen, Jepson Herbarium, Univ. Calif., Berkeley; Sharon Collman, Coop Extn., Wash. State Univ.; Sheila Daar, Daar & Associates, Berkeley, CA; Walter Ebeling, UCLA, Emer.; Steve Frantz, Global Environmental Options, Longmeadow, MA; Linda Gilkeson, Canadian Ministry of Envir., Victoria, BC; Joseph Hancock, Univ. Calif, Berkeley; Helga Olkowski, William Olkowski, Birc Founders; Orange oil is extracted from orange peels. It contains terpenes and George Poinar, Oregon State University, Corvallis, OR; Ramesh Chandra Saxena, terpenoids, and the major component is d-limonene. ICIPE, Nairobi, Kenya; Ruth Troetschler, PTF Press, Los Altos, CA; J.C. van Lenteren, Agricultural University Wageningen, The is very little chemical difference Hollingsworth 2005; Quarles 2006a). Netherlands. between the two. Food grade is Chang believes that d-limonene Manuscripts obtained by cold pressing the peels kills termites through its solvent The IPMP welcomes accounts of IPM for any to remove the oil, technical grade is activity. It actually “melts” or dis- pest situation. Write for details on format for manuscripts or email us, [email protected]. mostly obtained by steam distilla- solves their chitinaceous exoskele- tion. ton. This is consistent with the Citations There is a lot of misinformation known exoskeleton damage pro- The material here is protected by copyright, and may not be reproduced in any form, on the internet about termites and duced in the Formosan subter- either written, electronic or otherwise without orange oil. Some companies say ranean termite by a related chemi- written permission from BIRC. Contact cal, cis-nerol. Damage to the William Quarles at 510/524-2567 for proper that termites are killed by the citric publication credits and acknowledgement. acid in the oil. According to Chang, exoskeleton and cell membranes this is unlikely, because the orange causes lethal loss of proteins and Subscriptions/Memberships A subscription to the IPMP is one of the bene- oil they supply has less than 0.1% water (Zhu et al. 2003). fits of membership in BIRC. We also answer citric acid. Although their orange oil Orange oil is sold as a cleaning pest management questions for our members agent, and it is a good solvent. and help them search for information. contains 5% of other terpenes, alco- Memberships are $60/yr (institutions/ hols, ketones, and aldehydes that Because it is a good solvent, it can libraries/businesses); $35/yr (individuals). may have some activity, the major cause paint damage if used on Canadian subscribers add $15 postage. All painted surfaces. It is flammable, other foreign subscribers add $25 airmail active ingredient is about 95% d- postage. A Dual membership, which includes limonene. D-limonene (92%) is the but relatively small amounts of a combined subscription to both the IPMP registered active ingredient of the orange oil are used in a termite and the Common Sense Pest Control treatment (MSDS 2006). Quarterly, costs $85/yr (institutions); $55/yr termiticide XT-2000, and d- (individuals). Government purchase orders limonene termiticidal activity is accepted. Donations to BIRC are tax- Drywood Termite deductible. consistent with its known insectici- FEI# 94-2554036. dal properties against a variety of Treatments Change of Address flies, mosquitoes, ants, weevils, Drywood termites are found along When writing to request a change of address, fleas, wasps, crickets, mealybugs, the southern border of the U.S., please send a copy of a recent address label. scales, ticks, mites, and wood bee- and they are major pests in © 2008 BIRC, PO Box 7414, Berkeley, CA tles (Taylor and Vickery 1974; Styer 94707; (510) 524-2567; FAX (510) 524-1758. California and Florida.With global All rights reserved. ISSN #0738-968X and Greany 1983; Sheppard 1984; warming,their range is likely to Hink and Fee 1986; Coyne and Lott extend northward (Quarles 2007). 1976; Karr and Coats 1988; Karr et Treatment costs may exceed $500 al. 1990; Vogt et al. 2002; million each year (Su and Scheff- IPM Practitioner, XXX(1/2) January/February 2008 2 Box 7414, Berkeley, CA 94707 Update rahn 1990; Su and Scheffrahn be either a heat treatment or a tural fumigant is used (Lewis 2003; 2000). Drywood termites are either chemical fumigation, usually with Potter 1997). built into new structures, or they sulfuryl fluoride (Vikane®). Local Key to success with local treat- invade by flying in from outside. treatments are done with minimal ments is detection. Termite inspec- Unlike subterranean termites that disruption. Whole house treatments tion involves a trained and experi- live in the ground, drywood termites require that occupants move out of enced inspector. Inspectors are lim- spend most of their life cycle inside the house for about 3 days in the ited to accessible areas and rely a piece of wood. They live in hol- case of a fumigant, or leave for 4-8 mostly on their eyes to find termite lowed out spaces called galleries hours during a heat treatment signs such as damaged wood, flying (see Box A). (Quarles 2006b). termites (swarmers), discarded In California, drywood termite If there are a limited number of wings, and fecal pellets. Tools of treatments are either whole house accessible colonies of known loca- the trade include a flashlight and treatments or local treatments. tion, a local treatment is often used. wood probe such as an icepick, Local treatments include non-chem- In California, about 70% of the knife, or screwdriver (see Box A). ical methods such as heat, electro- time, customers choose chemical Over the years additional tools gun or microwaves or injections of injections, about 10% of the time, have been developed. Since termites chemicals directly into termite gal- they choose non-chemical methods, are encouraged by moisture, finding leries. Whole house treatments may and about 20% of the time a struc- moist areas can help with the ter- Box A. Biology of Drywood Termites Pest termites can be roughly divided into two kinds, four years to mature, and a colony of 1000 might take 7 subterranean and drywood. Subterranean termites live years to develop. To eradicate, colonies might have to be in the ground and forage in wood beneath and above the reduced to less than 20 termites (Lewis 2003; Lewis ground. The most economically important species are 2002; Ebeling 1975; Smith 1995; Kofoid et al. 1946). the eastern and western subterranean termite, Reticulitermes flavipes and R.