IntroductionAllelopathy occurs when one plant causes a deleterious effect on another plant through the release of allelopathic chemicals. Allelopathy may be used to protect against infections by fungal or bacterial organisms and/or may be a form of competition. Additionally, this form of competition could be used for succession or resource management. In this laboratory experiment, wheat (Triticum sp.) seeds were exposed to extracts from four plant species to determine whether or not these species develop growth inhibitors. The extracts were from goldenrod (Solidago sp.), aspen (Populus tremuloides), black cherry (Prunus serotina) and aster (Aster novae-angliae). Aspen is a deciduous tree native to North America. Aspen trees have shallow root systems, the ability to survive long-term flooding, and the formation of clones connected via root systems (USDA Forest Service “Species: Populus tremuloides”). Black cherries are widely distributed throughout the eastern United States, can grow on a wide variety of soils except very wet and very dry soils, can grow on highly acidic soils, can consist of multiple seedlings that germinate close to the parent tree, are intolerant to shade, are considered intolerant to competition and regeneration may have interference from some herbaceous plants through allelopathic chemicals. For example, Solidago rugosa releases chemicals from its leaves or roots that inhibit cherry succession. It has been suggested that black cherry may interfere with the regeneration of other tree species, such as red maple (Marquis “Black Cherry”). New England asters grow in humid environments and have a wide distribution in North America (Nesom “New England Aster: Symphyotrichum navaeangliae”). Goldenrods... half of the article... field observation and laboratory experiment to determine whether or not allelopathy was the contributing factor to succession on abandoned farmland. The researchers conducted laboratory biological analyzes and compared the results with those in the field. Looking at leaf extracts, long-term successional data, laboratory germination rates, and field observations to conclude that goldenrod succession was not due to allelopathic effects. Furthermore, inhibitory chemicals have a greater impact in control settings and not in the field, which was within their native range. Their theory was that soil organisms metabolized allelochemicals so rapidly that concentrations decreased and effects were minimized. On the other hand, in other studies it has been shown that allelopathy contributed to the invasiveness of Solidago Canadensis in Europe (Pisula & Meiners 2010).