###### Abstract  
Exotic ants and termites, including _Solenopsis invicta_, are frequent hitchhikers intercepted from miscellaneous nonfood commodities. In particular, _S. invicta_ has been intercepted in Korea in imported nursery plants, stone, and lumber products, which increases the potential for establishment of this destructive invasive pest in Korea. In this study, we conducted commercial-scale fumigation trials to evaluate ethyl formate (EF) as a potential alternative of methyl bromide using two species of imported rubber plants and pieces of marble as representative good and workers of _Reticulitermes spertus_ as an EF-resistant surrogate for _S. invicta_. An EF treatment at 35 g/m3 for 4 h at \(>\)15 \({}^{\circ}\)C, the dose required for LCto9% (lethal concentration \(\times\) time product required for 99% mortality of _R. spertus_), resulted in the complete control of _R. spertus_ workers tested with rubber plants (_Ficus benglalensis_ and _F. retusa_) and marble, 9% (\(w/v\)) and 60% (\(v/v\)) loading ratios, respectively. EF treatment did not adversely affect the leaf chlorophyll content, leaf color, and overall health of rubber plants or the visual appearance of the marble. Our results suggest that EF fumigation is a potential alternative to methyl bromide for the disinfestation of hitchhiking invasive termites and ants, including _S. invicta_, on imported rubber plants and stone products. e 2022126066. 202212606. (Hymenoptera: Formicidaeae), imported red fire ant, among the intercepted exotic ants and termites [8, 9]. This ant species is one of world's most aggressive and destructive invasive pests [10, 11], causing a wide range of economic and ecological problems once it is established [12, 13]. Native to South America, _S. invicta_ has invaded and established in many different countries, including Australia, China, Taiwan, and the United States [14]. It was first detected in Korea in 2017, and has been detected 14 times as of 2021 around importation points, such as ports, and as hitchhikers in imported lumber, stone, and nursery plants [3]. Fumigation is an effective and economical disintegration method to control exotic pests on various imported commodities [15, 16, 17] including nonfood products [9, 18, 19]. Methyl bromide (MB) has been widely used for such purposes, including ants and termites on imported nonfood commodities. For example, in Korea, the disintegration of termites and ants on nonfood commodities currently relies on a blanket provisional treatment of 48 g/m\({}^{3}\) MB at \(>\)15 \({}^{\circ}\)C for 24 h (T500-15) [3]. Imported lumber is an exception, which is treated by 24 h fumigation of 25-33 g/m\({}^{3}\) MB at \(>\)10 \({}^{\circ}\)C or 32-49 g/m\({}^{3}\) MB at \(>\)5 \({}^{\circ}\)C for termites and ants, respectively, depending on international regulations on lumber treatment (T400-1) [3]. Although most MB uses have been phased out due to its adversary effect on ozone layer depletion and human health [20, 21, 22, 23], a critical use exemption still allows for MB fumigation for quarantine and pre-shipment purposes. Therefore, there is a critical need to develop MB-alternative disinfection treatments. Ethyl formate (EF) is an MB alternative initially developed as a stored dried fruit fumigant in 1929 [24], and is considered to be a safe and effective alternative to MB [25, 26, 27] with no residues in commodities [28]. Recently, EF has been effective at controlling _S. invicta_[8], and an EF-based treatment (140 g/m\({}^{3}\) at \(>\)5 \({}^{\circ}\)C for 4 h) was developed for the control of _S. invicta_ in imported lumber using _Reticulitermes spertus_, the Japanese termite, as a resistant surrogate of _S. invicta_[9]. Since lumber and other nonfood commodities have different MB treatment requirements as indicated above, in this study, we tested the potential of using EF to disinfect _S. invicta_ on some of major nonlumber nonfood commodities, such as imported stone and nursery products. Here, we evaluate the efficacy of EF as a disinfection treatment intended for use against _S.