<p>We used meta-analyses to compare the effects of 44 single insect species used as biocontrol agents against invasive weeds with the effects of 51 species of non-biocontrol insects on native plants. The effects of biocontrol insects on plant morphometrics were stronger than those of non-biocontrol insects. Overall effects of both groups together were significantly different across plant growth forms with grasses, shrubs, and trees impacted more than vines and herbs. The effect of plant organ was also significant, with roots and fruits suffering the greatest impacts. Insect order had a significant effect:&#xa0;Hemiptera and Coleoptera showed strong effects and Diptera weak&#xa0;effects. Insect feeding guild had significant effects with leaf chewers, sap suckers, stem borers, and stem gallers having the strongest effects. There were no significant effects of study duration or latitude of location. For most categories of plant growth form, plant organ attacked, insect order and feeding guild, biocontrol insects had significantly stronger effects than their non-biocontrol counterparts. The effects of non-biocontrol insects grouped alone against native plants were not always a reliable guideline for how biocontrol insects grouped alone affected their target plants.</p>