The invasion of sugar maple stands or sugarbushes by ferns is becoming increasingly more common in Québec (Canada). The invasive fern species investigated in the present study are mainly associated with poorly drained soil that is periodically waterlogged and which has a forest humus layer >14 cm. The occurrence of invasive fern species in sugar maple stands is also related to an increase in the density of white-tail deer. In 2 experiments, various treatments aimed at promoting maple regeneration in stands invaded by Dennstaedtia punctilobula, were tested. Only the combination of liming and repeated mowing or flattening of the ferns led to a considerable increase in the density of maple seedling in the understory, reaching 15 to 28 seedlings/m2 after 3 to 5 years. Both repeated flattening of fronds and artificial shading of the understory also decreased frond density and height by at least 30%. The results highlight the complex interactions between openings in the forest canopy, the occurrence of invasive ferns, dear browsing and soil fertility that influence maple regeneration in sugarbushes.