Ecological upgrading of dry meadows in Liestal

In recent years, experts have been alarmed by the decline in many snail species. Species that live in dry meadows and ruderal areas are particularly affected. For this reason, the Hot Spots association launched various projects in five cantons in northern Switzerland to promote endangered snail species, such as the zebra snail ( Zebrina detrita ).

One of these upgrading projects was started in the winter of 2017/2018 in the Basel-Land municipality of Liestal. The aim of the upgrading was to clear two heavily overgrown embankments in order to obtain a predominantly open soil (between 50-75%), which is closely interwoven with a lean, rather low herb layer that receives a lot of direct sunlight and offers good retreat options in the soil.

During the first intervention in 2017, the rootstocks of the cleared trees were left in the ground. If they had been removed at that time, this would have seriously jeopardized the stability of the slope. The trees that were cleared were mostly dogwood ( Cornus sanguinea ), hazel ( Corylus avellana ) and field maple ( Acer campestre ). These trees have the property of repeatedly sprouting from the rootstocks. The shoots were cut back during each intervention with the aim of allowing them to dry out over the years.

As desired, a lot of light fell on the poor soil after the trees were cleared. Unfortunately, this also increased the pressure of neophytes. In particular, weeding the annual fleabane ( Erigeron annuus ) in spring took some time. Due to the proximity to the railway line, individual specimens of narrow-leaved ragwort ( Senecio inaequidens ) were also repeatedly found. In order to promote the open, gappy soil structure, native plants that tend to expand strongly, such as crown vetch ( Securigera varia ), field thistle ( Crisium arvense ) or common clematis ( Clematis vitalba ), were also weeded. After five years of targeted care, zebra snails from the neighboring pasture were relocated to the two embankments in summer 2023. The once bushy embankments have developed into species-rich areas that not only provide a suitable habitat for zebra snails. There is now a wide range of flowers, for example the common chicory ( Cichorium intybus ), the common viper's bugloss ( Echium vulgare ), the field scabious ( Knautia arvensis ) or the yarrow ( Achillea millefolium ).

For five years, the Nature Network was able to take over the maintenance of the two embankments on behalf of Hot Spots. The missions were very popular with both the operations managers and the community service workers. On the one hand, it was very exciting to see how the two areas developed over the years and, on the other hand, the ESB (Baselland Integration Center) invited us to a very tasty lunch each time.