Ranunculaceae
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RANUNCULACEAE
The Ranunculaceae are characterised by an enormous diversity: they are mostly herbaceous, but sometimes wooden; the flowers of most species are actinomorphous, but there are some with zygomorphous flowers; the number of sepals and petals is usually normal (five, sometimes four, six or eight); the flowers stand alone, in racemes or other forms; if there are less than ten pistils, these grow into long seed boxes after flowering; are there more than ten, they grow after flowering into round seed boxes. Often it isn't possible to separate the florescence of the of the plant. Mostly, the leaves are compound or cut in and some of them stand togther in a rosette near the root of the plant, while the rest stand along the stem.
The family of the Ranunculaceae comprises about 60 genera and 2000 species1. The family is globally dispersed, but most species are present in the temperate regions of the Northern hemisphere. Only very few species are adapted to extreme circumstances like tropical or Arctic climates. It is striking that the genus Ranunculus, with estimated 400 species one of the largest within the family, very widely is dispersed: from the tropics to the Acrtic region.
In the Netherlands are 34 species of thirteen genera present. Many species have in the past been imported by man, partially for use as ornamental plant and in less quantity for veterinary science2. The genus Ranunculus is represented throughout the Netherlands by many species. Some of these, like Ranunculus acris, Ranunculus repens and Ranunculus bulbosus are very common, in the Netherlands aswell as in (large parts of) the rest of Europe. Some other species are less widely dispersed. Because of preference of particular soils, like Ranunculus nemorosus which grows on loamy soils, or because the species reached the Netherlands by means of the rivers (especially the Rhine and the Meuse) and its dispersal is restricted to the riversides or the valley the river flows in. There were more species present in the Netherlands, but those are extinct in present times, partially because of copious manuring. Some of these species, which had isolated stands along the great rivers, maybe also because they were dispersed to the Netherlands by rivers which flow from the other climates (e.g. the Alps) and they weren't adapted to the Dutch climate.
In the Alps I have watched especially for members of the family for six days and the first two days I have seen several species without looking especially for Ranunculaceae. During these eight days I've been between 1200 and 2670 meters. I've seen eightteen species of eight genera in highly different vegetations. Of those eightteen species are six (of two different genera) present in the Netherlands. About a seventh species, Aconitum vulparia, are different books contradictory. It is certain that this species is present in Belgium and it could easily be brought to the Netherlands by means of the little river Geul. Of the other six species are five widely dispersed throughout Europe. Ranunculus acris and Ranunculus repens have been dispersed by man. Caltha palustris, Ranunculus bulbosus en Ranunculus trichophyllus grow near or in water and have probably been brought to the Netherlands by the rivers. The sixth species, Ranunculus nemorosus, grows on loamy soils and is therefor limited to a region in the far south of the Netherlands, called Zuid-Limburg3.
Of the six species which are also present in the Netherlands I've only seen Caltha palustris in the Alps above 2000 meters (tree-line). Four of the species seen in the Alps lower than 2000 meters are not present in the Netherlands. I've seen six species higher than 2000 meters, of which Caltha palustris, Ranunculus montanus and Trollius europaeus also lower than 2000 meters. Only one species, Ranunculus glacialis, was found higher than 2300 meters (snow-line).
Half of those species that are not present in the Netherlands are restricted to the (higher) mountains of Southern or Middle Europe. The other half are dispersed not only in the mountains of Europe, but also in (sub-) arctic regions, aswell in Europe aswell as in Northern America. Of those species existing only in the higher mountains of Europe are Aconitum compactum (sometimes called A. napellus subsp. vulparia), Ranunculus montanus, Aquilegia Atrata and Trollius europaeus endemic. Anemone narcissiflora (also known as A. narcissifolia), Caltha palustris, Ranunculus glacialis and Ranunculus trichophyllus exist not only in the Alps, but also in the arctic regions4. Ranunculus aconitifolius, Ranunculus platanifolius and Thalictrum aquilegiifolium are present in a large part of Europe, but not in the Netherlands5.
1 The sources deviate in this matter, partially because different authors handle different measures for including subspecies.
2 "Several genera of Ranunculaceae posess irritant properties from an innocious glycoside, ranunculin, which readily breaks down in bruised plant tissue by enzyme action to release protoanemonin, which is a volatile, strongly irritant, unstable oil." (Taken from: text of the Botanical Dermatology DatabaseIV). For this reason are Ranunculaceae not very popular by man and animal as food. Leaves of Anemone narcissiflora are being eaten by Eskimo's in Alaska.
3 Also on one spot near the city of Nijmegen, but there is already a rumour about the extinction there.
4 The first three for sure in Alaska, the last one not, but in Europe though.
5 The first two are endemic in Europe.
References:
I R. van der Meijden e.a., Heukels' Flora van Nederland, eenentwintigste druk, 1990, Wolters-Noordhoff Groningen, pp. 146-157;
II E.J. Weeda e.a., Nederlandse Oecologische Flora, deel 1, 1985, IVN Amsterdam, pp. 223-257;
IIIFlora Of America Online;
IV Botanical Dermatology Database;
V United States Department of Agriculture Natural Resources Conservation Service.
VI Flora Helvetica, 1996, K. Lauber & G. Wagner, Verlag Paul Haupt Bern.
The internetsites are dated 4/10/1998.