Roadside Banks, Verges and Ditches

As agriculture intensifies, rural roadsides are becoming more and more important for grassland flora. Many of the roads in the area are narrow, with relatively wide grassy verges or banks and deep ditches. They provide a refuge for many species which once grew in pasture or hay meadow which has now been ploughed for arable crops, or is mowed too early (because the farmer is making silage not hay now) to allow the wild plants to set seed.

Ecologists talk about flower-rich grassland a lot. It is the ideal habitat for many species of insects and should exist in vast swathes across Europe. Sadly it no longer does and its loss is one of the main reasons for severe declines in certain plant, bumble bee and butterfly species. 

These sorts of grassy banks and roadside verges are becoming an increasingly important habitat network, but for decades the local authorities have been making a rod for their own back by frequent mowing. The mowing and the fact that the clippings are not removed make for an ever increasingly fertile strip of land, with ever increasing rates of growth. Plants like nettles that thrive on the increased fertility multiply while plants like orchids that need low fertility decline. One good thing to come out of the economic recession is the willingness of those who control the purse strings to listen to the conservationists when they mention win-win approaches such as a reduction in mowing. It began with fauchage tardif (late mowing), which was a good start, but often resulted in local authorities mowing everywhere between 1 and 15 September, whether it was necessary or not. Now some authorities are displaying fauchage raisonné (intelligent mowing) signs. This is much better. These local authorities are restricting mowing at intersections to a short distance in each direction, and often not mowing at all in the autumn, but waiting to see if the frost will do their work for them. Not only does this save fuel, time and other resources, but the routine restores a more natural balance for the plant life, encouraging and protecting a wide range of wild flowers. Plus the shorter range of visibility means that drivers are more careful and drive slower.

With the pressure on natural environments from modern farming, roadsides are becoming more and more significant as repositories for certain sorts of wildflowers. Almost all of the substantial colonies of Early Purple Orchids Orchis mascula in Indre et Loire, for instance, are to be found on roadside verges. Other plants, such as the gorgeous intense blue Meadow Clary Salvia pratensis, are declining and more and more dependent on the relatively stable environment of grassy roadside banks.

It is the plants associated with prairie habitats that are most affected. Prairies are rough natural grassland, traditionally used as cattle pasture. Many of the wildflowers associated with this grassland are now rare and protected. Modern farming has either ploughed the prairie up to plant cereal crops, or 'improved' the pasture by sowing more nutritious grass mixes so they can send the stocking rate up. Either way the wildflowers are ousted to the margins. In addition, modern farmland is over fertilised as far as the native flora is concerned. Roadsides tend to remain poorer in terms of fertility, although still not natural, as car exhausts provide a lot of extra nitrogen.

Since 2008 the Conseils généraux (local authorities) of the départements (counties or shires) around us have been modifying their roadside mowing in order to encourage and protect the more delicate and vulnerable of these prairie wildflowers. Likewise, these plants need undisturbed soil, so their presence has to be taken into account when doing any heavy roadworks.

The département of Vienne has chosen 20 stretches of departmental road to erect signs warning motorists to stay off the roadsides to protect the flora. The blurb produced by the Regional Environment Observatory rather tartly advises that 'it is not worth slowing down to try to see the flowers - they are mostly very discreet and sometimes difficult to see, even if you are on foot!' They suggest that if you want to see the plants up close you have to go on an outing organised by Vienne Nature or one of their partners.

In Indre et Loire the signs announce that the Conseil général will be engaged in 'Intelligent Mowing' to preserve nature and Indre's signs say they are 'experimenting with late mowing'. The later the mowing, the less fertility from the cut grass will be returned to the soil, as it will be drier and more mature. The earlier and more frequently they cut the verges, the more lush green compost they will be returning to the soil, causing it to become eutrophic, with the result that plants like nettles dominate.

It all amounts to a campaign to educate the public about the importance of roadside vegetation as a refuge for once common and ubiquitous species, as well as a welcome means of justifying a reduced mowing regimen, thus reducing road maintenance costs. It's a simple thing that will make a big difference and everybody wins, but in garden and streetscape manicure obsessed France it is quite a big step.

The sign says 'Protect the flora on the side of the road' (by not pulling off onto the grass and driving on it or parking on it).
The sign is situated on a rural road near Coussay le Bois. There are orchids and other wildflowers growing on the verge.
The sign says 'Intelligent mowing -- Nature preserved'. This means the local authority has a policy of mowing late in the season, after everything has had a chance to seed, and only in places where road safety is compromised by rank vegetation.

A grassy rural roadside bank near Panzoult. The soil here is calcareous, part of a limestone ridge, and the bank not mown too frequently. The grass is full of Meadow Clary Salvia pratensis, Bee Orchid Ophrys apifera and other wild flowers.
Members of the Association de Botanique et de Mycologie de Sainte Maure de Touraine check out a Military Orchid Orchis militaris on a roadside bank in the Claise Valley. Military Orchids are rare, but there are two small colonies in the Claise Valley, both on roadside banks.

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