2010 will be the
UN International Year of
Biodiversity, and what
could be more auspicious
than the discovery of
an endangered species
growing in the UN park?
The “Corn Mignonette”, a species belonging to a family of plants renowned for their medicinal properties, was discovered last June, growing in the area disturbed by the Genève-Lac-Nations project. This 35 million franc project to develop an environmentally-friendly way to cool the UN and other buildings by using water from Lake Geneva has had an additional and unexpected benefi t of providing habitat for the Corn Mignonette, as well as a number of other threatened plant species. The Corn Mignonette (Latin name Reseda phyteuma) is listed as “endangered” in both the Swiss as well as the Geneva Red Lists of threatened plants, and it is a huge surprise that it should turn up on UN grounds. Its seeds have probably lain dormant in the soil for years just waiting for this opportunity to grow.
Plant life in Switzerland is very rich given the variety of habitats and altitudes in the country, but sadly nearly a third of the three thousand plant species growing in the country have been identifi ed as threatened with extinction – including the Corn Mignonette. The reasons for this are many, but a major problem is that many native plants cannot grow in soil that has either been enriched by chemical fertilisers (those which make lawns nice and green), or else by dung from livestock such as cows and sheep. “Poor” soil is something that has become very rare throughout Europe. The UN now manages much of its park without the addition of chemical fertilisers and keeps extensive meadows, which is very good for some of the native plant species and their associated insects and birds. However most of the soil in the meadows is still very “rich” due to the use of chemical fertilisers in the past (which continue to have enriching effects decades later), as well as from sheep. Therefore while the meadows are very pretty, species diversity is still rather low, although with time and proper management one hopes this will improve.
The Corn Mignonette can only grow in poor, unfertilised soil that has been recently disturbed, conditions which were created by the recent construction work along the narrow strip of land at the bottom of the UN Park near the Sécheron exit. In addition, over eighty other species have been observed growing in this relatively small area (about 300 m long by 10 m wide) to date, including others listed in the Swiss Red List such as Weld (Reseda luteola), Annual Woundwort (Stachys annua) and Moth Mullein (Verbascum blattaria). Other less threatened but beautiful species such as Poppies (Papaver rhoeas) and Self-Heal (Prunella vulgaris) also cheered the landscape this summer. Surprisingly a number of these species have medicinal properties, so perhaps colleagues from WHO (which is also being cooled thanks to the lake water project) might be interested in paying a visit to this site.
So what can be done to conserve this astonishing little patch of rare species that has turned up on UN grounds? As these plants grow in disturbed places and cannot compete with other species where the soil is richer, it is essential not to fertilise or add additional soil to level the site, nor to plant grass. Doing so would damage the area to the point that the endangered Corn Mignonette and its associated rare plants could no longer survive. A management plan is urgently needed to work out how to maintain this habitat, which may include local, manmade disturbance during the non-flowering season. An information panel explaining why and how this part of the park is being managed could be erected. The area may not look as "tidy" as would a grassy lawn, but biodiversity is not tidy, and the UN should lead by example if we are truly going to conserve the vast number of species on which our wellbeing depends. Let's make an effort for the UN Year of Biodiversity to act locally while thinking globally!