We use -32c for 72 hours with a 24hr reacclimating period. Wrapped in polyethylene bags and tied or taped shut of course. In my opinion...6" of wood is nothing to -20c to -32c the core will get that cold in a mater of a few hours which is faster than most critters could develop an "internal antifreeze". It is the fast drop in temp that destroys all life cycles. JTV
Joel Voron Colonial Williamsburg Foundation Conservation Dept. Integrated Pest Management Specialist Office 757-220-7080 Cell 757-634-1175 E-Mail jvo...@cwf.org ________________________________________ From: pestlist@googlegroups.com <pestlist@googlegroups.com> on behalf of nicole...@gmail.com <nicolegra...@gmail.com> Sent: Thursday, April 11, 2024 1:43 PM To: MuseumPests Subject: [PestList] Re: Freezing Time You don't often get email from nicolegra...@gmail.com. Learn why this is important<https://aka.ms/LearnAboutSenderIdentification> [CAUTION: This message originated from outside the Foundation. Do not click links, open attachments or take action unless you know the contents are safe] Hello Todd! My protocol for wood borers is to vaccum all frass, dust, and insect detritus before freezing. Then I place the item on a clean sheet of blotter paper, wrap, and freeze for 72 hours. Our freezer gets down to -26 C. What's important is that after freezing I allow the artifact to rest undisturbed for 1-2 weeks. Then I unwrap it, tap it gently all over, and watch for new frass coming out. Any new frass is an indication that the infestation is still active and the treatment (including vaccuming) needs to be repeated. This is the same protocol I follow for other insects, but I find that I commonly need to repeat treatment on wood boring insects 2 or 3 times before they are frass-free. In my understanding and experience, wood borers are well-evolved for handling winter temperatures, but the repeated shock of extreme cold will ultimately prevail. Nicole Nicole Grabow she / her / hers Director of Preventive Conservation Midwest Art Conservation Center 2400 Third Avenue South Minneapolis / Bde Óta Otúŋwe, MN 55404 (612) 870-3129 http://www.preserveart.org/<http://www.preserveart.org/> On Thursday, April 11, 2024 at 12:08:51 PM UTC-5 thol...@artsmia.org wrote: Hello Pestlist- Our normal freezing cycle is "one week" (load in on Mon - load out next Mon etc). This has always been thinking about moths. We recently prepared a wooden object for freezing that shows a history of wood boring insect activity. We are 99.9% sure it is not an active infestation, but want to get it on the record as having been treated. I was curious- How long do people freeze objects when thinking about wood boring insects? The wood is 5"-6" inches thick in places. Any thoughts people might have would be appreciated. Thanks, Todd -- You received this message because you are subscribed to the Google Groups "MuseumPests" group. To unsubscribe from this group and stop receiving emails from it, send an email to pestlist+unsubscr...@googlegroups.com<mailto:pestlist+unsubscr...@googlegroups.com>. To view this discussion on the web visit https://groups.google.com/d/msgid/pestlist/b4f197d1-70fa-447c-848c-8557e02317b5n%40googlegroups.com<https://groups.google.com/d/msgid/pestlist/b4f197d1-70fa-447c-848c-8557e02317b5n%40googlegroups.com?utm_medium=email&utm_source=footer>. -- You received this message because you are subscribed to the Google Groups "MuseumPests" group. To unsubscribe from this group and stop receiving emails from it, send an email to pestlist+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/pestlist/MN2PR20MB3120B04A6EDCBD22042AED7CDC052%40MN2PR20MB3120.namprd20.prod.outlook.com.