Voorkomen en standplaats van Gagea lutea (L.) Ker-Gawl. in Nederland

Gagea lutea (L.) Ker-Gawl. is a rather rare species in the eastern part of the Netherlands, occurring chiefly in the so-called Drenthian and Subcentral European districts; besides, it is recorded from some findspots in the province of North-Holland (fig. 1). A number of records of G. lutea in literature in fact refer to other species, especially G. pratensis; a survey is given of false and doubtful records. According to HILLEGERS (1970) and TEN KLOOSTER & LANJOUW (1972), in the Drenthian district G. lutea is chiefly found in gardens and lawns and on treaded places in the shade of trees, nearly always growing within or in the close vicinity of human settlements. Inter alia, it occurs in so-called „stinse milieus” (i.e., woods and parks near old buildings like castles, countryseats, churches and so on, with a herb layer that is partially spontaneous, partially consisting of old medicinal and ornamental plants) in the province of Groningen and on some places outside. In the present paper, three additional types of habitat of the species are described, viz.: 1°. woods on the banks of brooks and rivers (in the eastern parts of Gelderland and Overijssel); 2°. woods at the foot of slopes, often on spots with horizontally moving water in the subsoil (this type of habitat is very rare in the south-eastern part of the Netherlands and on the inner side of the dunes; one of the most beautiful localities has been destroyed); 3°. brushwoods on the outskirt of coppice woods (in a few places in the north of Drenthe and the east of Overijssel). Table 1 comprises a number of „releves” (1—23) of these three types of habitat. They show a rather large amount of mutual similarity in vegetation composition. They are obviously richer in woodland species and nitrophilous penumbra herbs than the vegetation in the previously mentioned treaded places, lawns, etc. (24—27). Because all localities of G. lutea in the Drenthian district represent anthropogenic habitats (for also the brushwoods mentioned sub 3° are heavily influenced by men), probably it must be looked upon as an archaeophytic species in this part of the Netherlands. In the south-eastern part of the country, however, G. lutea is a part of the original woodland vegetation; its localities in this region connect with similar localities in Germany and Belgium. The four Gagea species that occur in the Netherlands constitute an ecological series in the order G. villosa— G. pratensis—G. lutea—G. spathacea. While G. villosa (rare in our country nowadays, showing a stronger decline than the other species) is restricted to habitats strongly influenced by men (treaded places and lawns; previously also in arable land), G. pratensis occurs in the same habitats but is also found sometimes in vegetations that are to a lesser degree anthropogenic. G. lutea is restricted to anthropogenic habitats only in a part of our country, growing in woods with a spontaneous herb layer elsewhere, while G. spathacea is nearly always found in semi-natural woods.