IntroductionAllelopathy occurs when one plant causes a deleterious effect on another plant through the leakage of allelopathic chemicals. Allelopathy may be used to protect against infections from 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 seeds (Triticum sp.) were exposed to extracts from four plant species to determine whether or not these species process growth inhibitors. The extracts were from goldenrod (Solidago sp.), aspen (Populus tremuloides), black cherry (Prunus serotina), and aster (Aster novae-angliae). The trembling aspen is a deciduous tree native to North America. Aspens have a shallow root system, the ability to survive long-term flooding, and the formation of clones connected by 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 strongly acidic soils, can consist of several Plants that germinate close to the parent tree, are shade intolerant, are considered intolerable to competition, and regeneration can be disrupted by some herbaceous plants via allelopathic chemicals. For example, Solidago rugosa releases chemicals from the 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 the red maple (Marquis “Black Cherry”). New England asters grow in a humid environment and are widely distributed in North America (Nesom “New England Aster: Symphyotrichum navaeangliae”). Goldenrods......middle of article......field observation and laboratory experiments to determine whether or not allelopathy was the contributing factor to succession on abandoned farmland. The researchers carried out biological tests in the laboratory and compared the results to those in the field. Examination of leaf extracts, long-term succession data, laboratory germination rates, and field observations allows the conclusion that goldenrod succession was not due to effects allelopathic. Additionally, inhibitory chemicals have more impact in control settings and not in the field, which was within their original range. Their theory was that soil organisms metabolized allelochemicals so quickly that concentrations decreased and effects minimized. On the other hand, allelopathy has been shown in other studies to have contributed to the invasiveness of Solidago Canadensis in Europe (Pisula & Meiners 2010).