Biochar mitigation of allelopathic effects in three invasive plants: evidence from seed germination trials

Many invasive species show allelopathic effects that contribute to competitive impacts on native vegetation for which few control measures exist. We investigated the potential pyrolized organic material used as a soil amendment (“biochar”) sorb allelochemicals and mitigate seed germination early seedling development in three common plants Canada: garlic mustard (Alliaria petiolata), tree of heaven (Ailanthus altissima), yellow sweetgrass (Melilotus officinalis). hypothesized biochars would (radicle extension cotyledon development) through sorption allelochemicals. Laboratory assays two agricultural crops (Lactuca sativa Raphinus raphanistrum) grass (Andropogon gerardi Poa palustris) were conducted using water extracts from leaves. Seeds treated with plant exposed four different (red oak (Quercus rubra), jack pine (Pinus banksiana), shipping pallet construction waste, high-carbon wood ash) range extract biochar dosages. Treatment by significantly (p < 0.05) mitigated Alliaria Melilotus. Effects depended concentration, dosage, target assessed. Controls leachate alone showed increased tested (jack ash). Results indicated can allelochemicals; however, this will be effective only some cases.