The present invention relates to methods of controlling and/or preventing soil-dwelling pests in useful plants comprising applying to the locus of the useful plant or treating plant propagation material thereof with a compound of formula (I) wherein —B1—B2—B3— is —C═N—O—, —C═N—CH2—, —C═CH2—O— or —N—CH2—CH2—; L is a direct bond or methylene; A1 and A2 are C—H, or one of A1 and A2 is C—H and the other is N; X1 is group X, formula (X) R1 is C1-C4alkyl, C1-C4aloalkyl or C3-C6cycloalkyl; R2 is chlorodifluoromethyl or trifluoromethyl; each R3 is independently bromo, chloro, fluoro or trifluoromethyl; R4 is hydrogen, halogen, methyl, halomethyl or cyano; R5 is hydrogen; or R4 and R5 together form a bridging 1,3-butadiene group; p is 2 or 3. Preferably the soil-dwelling pest is selected from corn rootworm, wireworms, grubs, in particular white grubs (e.g. Phyllophaga sp., Diloboderus sp., Popillia japonica), termites (in particular for sugar cane), subterraneous stinkbugs (e.g. Scaptocoris sp.), cutworms (e.g. agrotis sp.), millipedes (e.g. Julus sp.) and broca gigante (e.g. Telchin licus).