Hello Katy, I cannot comment on the effectiveness of killing those specific pests in a -15C with a double freeze.
I do want to warn strongly against putting dry ice in your freezer! Please read any material safety sheets related to this and ask an EH&S expert, but my understanding is that dry ice must be in a proper container or else a buildup of gas can cause major problems and be very dangerous. If your materials are not sensitive to heat and you have the right weather you might be able to do a black bag style treatment outside? I also see on Index Herbariorum there are 2 herbaria in Price and perhaps one of them has a large and cold enough freezer you could use? Manti-LaSal National Forest, USDA Forest Service<http://sweetgum.nybg.org/science/ih/herbarium-details/?irn=125214> Utah State University – Eastern<http://sweetgum.nybg.org/science/ih/herbarium-details/?irn=124312> Best of luck Genevieve ================================================= Genevieve E. Tocci Senior Curatorial Technician Harvard University Herbaria 22 Divinity Ave., Cambridge, MA 02138 U.S.A. Phone: 617-495-1057 Fax: 617-495-9484 [email protected]<mailto:[email protected]> From: [email protected] <[email protected]> On Behalf Of katharine.corneli Sent: Wednesday, June 05, 2019 6:03 PM To: Museumpests <[email protected]> Subject: [pestlist] Freezing as treatment/prevention Hello all, We have a Navajo rug and native basketry exhibit coming in to our changing exhibits gallery and several of the rugs have shown webbing-like residue and one of the baskets has frass in the spaces between the weaving. I recently put some data loggers in our chest freezer and it only goes down to about -15 degrees C. I have read that -30 C is recommended but I would imagine it varies by pest. Is it possible that webbing clothes moths and, say, drugstore beetles are killed at higher temperatures? I realize I am dreading talking to the curator and the director to tell them we either can't take these items for the exhibit or we need to buy a new freezer. Is there some way to achieve a good kill rate without such a low temperature? Repeated freeze/thaws etc? Could I add some dry ice? Rig something up to make it colder? It has also proven difficult to source local commercial freezers. I realize we will need to replace it eventually but my director is generally reluctant to spend money (I'm sure none of you can relate....) and I wonder if we can pull something together at least for this exhibit. Thank you for any input, Katy Katharine Corneli Curator of Collections | Prehistoric Museum 155 E Main, Price, Utah 84501 Office: 435-613-5765 Email: [email protected]<mailto:[email protected]> -- 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 [email protected]<mailto:[email protected]>. To post to this group, send email to [email protected]<mailto:[email protected]>. Visit this group at https://groups.google.com/group/pestlist<https://urldefense.proofpoint.com/v2/url?u=https-3A__groups.google.com_group_pestlist&d=DwMFaQ&c=WO-RGvefibhHBZq3fL85hQ&r=EYdhJ0HrhAMcA2aVQ-I4N7lml00zxsXPbHYeP7843No&m=a4d8FGauTg91Iaz-8yFUqNuAcXbrzuMxN1vdrPtwLXw&s=f4hJhPESXF4WtO-PwQ77l1tlAxeIma1SkoCBSxHggtE&e=>. To view this discussion on the web visit https://groups.google.com/d/msgid/pestlist/98b19e9c-4aff-4622-891a-1cc3673948b0%40googlegroups.com<https://urldefense.proofpoint.com/v2/url?u=https-3A__groups.google.com_d_msgid_pestlist_98b19e9c-2D4aff-2D4622-2D891a-2D1cc3673948b0-2540googlegroups.com-3Futm-5Fmedium-3Demail-26utm-5Fsource-3Dfooter&d=DwMFaQ&c=WO-RGvefibhHBZq3fL85hQ&r=EYdhJ0HrhAMcA2aVQ-I4N7lml00zxsXPbHYeP7843No&m=a4d8FGauTg91Iaz-8yFUqNuAcXbrzuMxN1vdrPtwLXw&s=CaZy8KYnfyxW1vMiZi28KcYfCvwxRQR_dQJVEKHWg90&e=>. For more options, visit https://groups.google.com/d/optout<https://urldefense.proofpoint.com/v2/url?u=https-3A__groups.google.com_d_optout&d=DwMFaQ&c=WO-RGvefibhHBZq3fL85hQ&r=EYdhJ0HrhAMcA2aVQ-I4N7lml00zxsXPbHYeP7843No&m=a4d8FGauTg91Iaz-8yFUqNuAcXbrzuMxN1vdrPtwLXw&s=pW7qcxNMTLIa1ApsCAezM0bUbez01xCXrSXRkNVnV00&e=>. -- 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 [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/pestlist. To view this discussion on the web visit https://groups.google.com/d/msgid/pestlist/BN8PR07MB63370D0EE3774A54D5D44B51D5170%40BN8PR07MB6337.namprd07.prod.outlook.com. For more options, visit https://groups.google.com/d/optout.
