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The contributions of soil arthropods to entomopathogenic nematode (EPN) food webs are mainly studied in artificial conditions. We investigated changes in arthropod communities in a citrus orchard following soil inundation with <i>Steinernema feltiae</i> or <i>Heterorhabditis bacteriophora</i>. We hypothesized that arthropod taxa, which decline or increase in response to EPN augmentation, represent potential prey or predators of EPN, respectively. Soil was sampled periodically after nematodes were applied, DNA was extracted from organisms recovered by sucrose centrifugation, libraries were prepared, and the ITS2 and CO1 genes were sequenced using Illumina protocol. Species from 107 microarthropod (mites and collembola) families and 121 insect families were identified. Amplicon sequence variant (ASV) reads for <i>H. bacteriophora</i> were less than 10% of those for <i>S. feltiae</i> three days after inundation, whereas microarthropod ASVs were double in plots with <i>H. bacteriophora</i> compared to those with <i>S. feltiae</i>. Significantly fewer microarthropod and insect reads in <i>S. feltiae</i> compared to untreated plots suggest the possibility that <i>S. feltiae</i> preyed on mites and Collembola in addition to insects. The responses over time of the individual microarthropod species (MOTU) suggest that regulation (up or down) of these EPN resulted from a cumulative response by many species, rather than by a few key species.