Strengthening remaining populations of Jurinea cyanoides in the northern Harz foreland and along the Saale River, as well as monitoring other populations in Saxony-Anhalt

Jurinea cyanoides is listed as a priority species in Annex II of the Fauna-Flora-Habitat Directive. This means that populations with an unfavorable conservation status must be improved and deterioration of populations with a favorable conservation status must be prevented. The competitively weak Jurinea cyanoides is highly adapted to dry conditions and colonizes continental sandy dry grasslands. It is listed as highly endangered (RL 2) in the Red Lists of Germany and Saxony-Anhalt. In Germany, the largest populations are found in Hesse, Baden-Württemberg, and Saxony-Anhalt. Apart from the populations in Germany, there is only one population in Central Europe, in Czechia.

The change or complete disappearance of historical forms of land use, such as grazing, burning, and sod cutting, led to a deficit in the use and maintenance of a large part of the Jurinea cyanoides populations. Together with increased atmospheric nitrogen deposition, this has resulted in matted and litter-rich stands, some of which are overgrown with scrub, with a lack of suitable raw soil areas for establishment. These site conditions have caused a sharp and ongoing decline in Jurinea cyanoides. At the start of the project, there were 19 current sites in Saxony-Anhalt, compared to at least 46 extinct sites. Five populations consisted of fewer than 100 rosettes. In order to prevent the extinction of populations with few rosettes, to increase the size of the populations, and to preserve Jurinea cyanoides in the long term, suitable management measures must be taken to improve site conditions in existing populations and create new sites.

Project priorities

In the projects run by Anhalt University of Applied Sciences since 2008, a total of eleven locations in Saxony-Anhalt have seen reintroductions, population increases, and conservation measures to promote Jurinea cyanoides

Project region

All project areas are located within Saxony-Anhalt and can be divided into three regions: the Elbe region with populations near Gerwisch, Lübs, Gödnitz, and Steckby; the Saale region with the last remaining population of Jurinea cyanoides near Wettin; and the northern Harz foreland region, whose populations are shown on the map.

Further project details

• Population enhancement

  In the Elbe region, Jurinea cyanoides grows on dune sands. In the winter of 2008/2009, restoration measures were carried out at the three sites located in the Mittelelbe Biosphere Reserve: Lübser Heuberg, Sandtrockenrasen nördlich Gödnitz, and Alter Heutrockenplatz nahe Steckby. By removing the topsoil with a chain loader and applying nutrient-poor sand to an area of 500 to 1700 m², we pushed back sand sedge (Carex arenaria), small reed grass (Calamagrostis epigejos) and other highly competitive species, creating a large area with little competition. In Gödnitz, the sandy grassland was enlarged by removing Scots pines (Pinus sylvestris) and black locusts (Robinia pseudocacia). To strengthen the previously approximately 100 rosette populations near Gödnitz and Steckby, we introduced 1500–3000 seeds, some of which had been propagated, from the nearby Lübser Heuberg – the largest population in Saxony-Anhalt. The measures were accompanied by the distribution of leaflets in surrounding communities. With approximately 50,000 rosettes, the population near Gödnitz is currently the third largest in Saxony-Anhalt, alongside Lübser Heuberg and Weinberg Ost.

  The current project involves population reinforcement in the northern Harz forelands at Großer Thekenberg near Harsleben, at the Rümken and Kleiner Lehof quarries near Westerhausen, and on the sandy dry grassland north of Gerwisch near Magdeburg. Some of the areas need to be cleared to a depth of about 5 cm using brush cutters in order to create enough open ground for seed dispersal.

  A seed propagation culture is to be established for the population near Mücheln (Wettin) during the project period. The particular difficulty here is that it is only possible to collect seeds from the population in years with sufficient rainfall, as otherwise drought stress prevents flowering and seed ripening, even in the case of Jurinea cyanoides.

  

  

• Resettlements

  In spring 2010, a reintroduction took place in the northern Harz foreland near Blankenburg, close to the extinct site of Sassenberg. As part of a compensation measure, several sand hills covering a total area of 6 hectares were created here. We planted around 6,000 seeds on the sparsely vegetated southern side of the Ost vineyard. Most of the seeds used for propagation came from the Großer Thekenberg. In fall 2013, approximately 7,100 rosettes of Jurinea cyanoides were growing on the eastern vineyard.

  In 1983, a now extinct population of Jurinea cyanoides was mentioned for the Mühlberg near Steckby. By removing stands dominated by Carex arenaria and applying nutrient-poor sandy soil, we created low-competition conditions here on 1600 m² in the winter of 2010/2011. We then introduced approximately 8,000 seeds of Jurinea cyanoides, which originated from Lübser Heuberg and were propagated in the protected garden of the Mittelelbe Biosphere Reserve. In the fall of 2013, an extrapolation from 2 x 100 areas yielded approximately 16,000 rosettes, many of which were young plants.

  In the winter of 2011/2012, 2,000 seeds taken from Lübser Heuberg were used to establish a population of Jurinea cyanoides in the Oranienbaumer Heide. Extinct sites are known in the same main natural area, the Elbe-Mulde lowlands, for example near Mosigkau, approximately 15 km away. Extensive grazing with Heck cattle and Konik horses on approximately 750 hectares has initiated dynamic processes in the Oranienbaumer Heide again. Here, the establishment of Jurinea cyanoides during ongoing soil disturbance is being investigated.

  

  

• Additional project tasks

  The Jurinea cyanoides populations at Günthermannskopf (Harz foreland), Steckby, and Gödnitz (Elbe) are mowed low. In Mücheln, sheep graze the area and in winter, the area is maintained by removing woody plants. Goat grazing on three populations in the Harz foothills is being monitored by experts. The aim is to have grazing at least at one or more locations. Follow-up maintenance is also carried out at the four sites where reintroduction and population reinforcement have taken place by removing woody plants and mowing. The scientific experiments in Gödnitz, Steckby, and the Oranienbaumer Heide are being studied and documented over the long term. Since 2021, general monitoring of almost all populations of the sand Jurinea cyanoides in Saxony-Anhalt has also been initiated in order to compare the development of the populations and, if necessary, derive any need for action.

  Furthermore, Jurinea cyanoides offspring are being cared for at Anhalt University of Applied Sciences and the Teufelsmauer conservation garden in cooperation with the Förderverein Teufelsmauer e.V. (Teufelsmauer Association).

  

  

• Monitoring of conservation success and results

  In the winter of 2008/2009, an experiment using a Latin square design was set up at the Gödnitz and Alter Heutrockenplatz population enhancements. In this experiment, we are investigating various restoration measures to promote Jurinea cyanoides and the site requirements of the species. The management variants 1) topsoil inversion, 2) topsoil inversion with sod filling, 3) mowing, and 4) initial stock without restoration are compared with four replicates each. For each management variant and replicate, the germination and mortality rates of 50 introduced and marked Jurinea cyanoides seeds are examined and vegetation development is documented using recordings according to Zacharias (1996).

  

  

  The highest number of living and flowering Jurinea cyanoides and the largest rosettes are found in vegetation-poor stands of topsoil inversion. Stands created by topsoil inversion and sod deposition with less competitive sand specialists such as silver grass (Corynephorus canescens), farmer’s mustard (Teesdalia nudicaulis), and small sorrel (Rumex acetosella) are significantly less suitable for the establishment of silver grass. Denser vegetation stands created by mowing and initial stands (from approx. 50% herb layer, 70% cryptogams, 10% raw soil) are hardly suitable for Jurinea cyanoides. The results suggest that many populations of sand Jurinea cyanoides in Saxony-Anhalt are in advanced stages of age, as dense vegetation stands allow little or no generative regeneration.

  

  

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• Outlook

  The Jurinea cyanoides will continue to require intensive protection measures that preserve or recreate nutrient-poor sandy areas. In addition to preserving current populations, reintroduction to suitable locations is also necessary. The maintenance and monitoring of the populations described above will continue in the coming years. The recent increase in the proportion of grazed populations of Jurinea cyanoides (eight out of 19 in Saxony-Anhalt are currently grazed) is to be welcomed. Here, grazing must continue to be adapted to the specific requirements of Jurinea cyanoides and optimized in terms of the thinning of the herbaceous layer necessary for generative regeneration. Efforts should be made to include populations that are not currently grazed in grazing programs. Populations that are not suitable for grazing due to poor conditions should be maintained by mowing very close to the ground.