Species rich road verges
Vegetation-covered strips along our roads can be valuable habitats, supply food resources or act as dispersal corridors for many species of plants, fungi and animals.
As the Swedish Transport Administration points out, many plants that were previously common in the cultural landscape such as Pasqueflower (Pulsatilla vulgaris), Wolf's Bane (Arnica montana), Bristly Bellflower (Campanula cervicaria) and Catsfoot (Antennaria dioica), today often only remain in small relict stands along roads. If this development continues, road verges can become particularly important refuge habitats and proper road maintenance an important factor for the conservation of species.
In Sweden, the Swedish Transport Administration (Trafikverket) is responsible for the management of the verges along the state roads. Therefore, the authority has already in the 90s started to inventory roads to identify road verges with high ecological value with the main goal of preserving and developing these stretches. In 2012, the Swedish Transport Administration also developed an inventory methodology to be able to define species-rich roadside objects (which are then marked with special signs) and divide these into different value classes (class 1-3 and class 4 – objects of consideration) using a standardized methodology.
According to the Swedish Transport Administration, species-rich road environments are defined as “road side areas that indicate at least one of the following points:
- Holds red-listed species, species of responsibility, rare species and/or indicator species.
- Have a special species composition based on complex soil and structural properties and/or has a particularly high species richness or frequency of indicator species.
- Provides a substantial ecological resource, for example for reproduction, life cycle, protection or food.
- Constitutes an important environment and has geological and ecological conditions for species dispersion and connectivity in the landscape.”
Unfortunately, invasive plants such as the Garden Lupine (Lupinus polyphyllus) are invading a high proportion of species-rich roadside objects. Since invasive species often develop dense dominant stands, many small native roadside plants are outcompeted and disappear from these roadside habitats. Our project aims to develop cost-effective management methods to control and repel invasive species with the aim to preserve the diversity and ecosystem functions of species-rich road verges.
You can read more about species rich road verges here (in Swedish):
Swedish Transport Administration – Artrika vägkanter
Swedish Transport Administration – Inventering av artrika vägkantsmiljöer
Skogskunskap – Artrika vägkanter