Fructification in Dutch Maianthemum bifolium populations

Aspects of fructification in Maianthemum bifolium were studied, mainly in natural populations in The Netherlands, but also in additional laboratory experiments. C. 15% of the plants were found to produce flowers. On an average 25.1 + 3.59 flowers and 2.7 ± 2.24 fruits were established per fruiting plant, and a mean of 1,2 fruits per flowering plant. It was ascertained that at soil pH < 4 generally more fruits were produced than at higher pH values. At a coverage of > 35%, a highly positive correlation was found to exist between the coverage percentage of undergrowth and the number of fruits produced. A presumed positive effect of the undergrowth via a raised air humidity on fruit production was affirmed by laboratory experiments. Syrphidae appeared to be the most important pollinating insects. However, insect pollination did not appear to be decisive for fruit production.