As already written above, xerothermic grasslands are an assemblage of semi-natural vegetation, which means that they will not survive on their own, but only in partnership with people. Most of the grassland habitats throughout Europe maintain their open character through extensive use, mostly by grazing, more rarely by mowing, burning and even by sporadic plowing (!). For this reason, simply bringing such habitats under legal protection as reserves or environmental use areas is not enough. Just several decades ago, any human use of grasslands was considered a negative factor in their preservation. It was then that many valuable xerothermic grasslands were "closed" by making them into reserves and any type of use previously made of them - grazing, mowing, burning - was banned. This initiated the process of secondary succession, which quickly led to the transformation of formerly open grassland assemblages into thermophilous scrub and forests. The result is a drastic decrease in the number of xerothermic species - the reason for creating the reserve in the first place. Paradoxically, reserves protecting fragments of thermophilous vegetation are some of the most threatened sites of these rare habitats.
Fortunately, today we are informed by the negative experiences of our predecessors and we have greater knowledge about the establishment and maintenance of xerothermic grasslands. We know that their preservation depends on specific management methods.
The foundation is good grazing!
The main management method of xerothermic grasslands related to extensive herding practices is grazing. The practice of putting out mixed herds of sheep, goats and single individuals of cattle and horses to pasture was frequently used. Generally, the oldest and most primitive breeds of livestock (wrzosówka sheep - a breed derived from ovis brachyra borealis, ¶winiarka sheep, konik polski - Polish primitive horse, various goat breeds) are most suitable on such extreme habitats with their poor food base.
The selective grazing of sheep, which choose the more delicate plants and avoid those with a xeromorphic structure, regulates the species' composition of xerothermic grasslands - eliminating invasive meadow and ruderal species while leaving the xerothermic ones. Domestic animals limit the spread of shrubs and trees naturally. They leave the thicker and older vegetation, and by grazing the open surface of the grasslands, promote the creation of a dynamic mosaic, which leads to a greater diversity of xerothermic habitats. The great heterogeneity of these habitats leads in turn to greater biodiversity. Additionally, domestic animals trample the ground while grazing, destroying in places layers of dead vegetation that negatively impact the development of xerothermic species. The trampling action bares patches of soil, which enables sunlight to reach lower levels of the surface so that light-demanding grassland seedlings can develop and the soil's seed bank can be activated.
It is important to remember that grazing has a positive impact on grasslands only when it is extensive. Too large a herd on too small an area can lead to the destruction of valuable xerothermic plants. In Poland, to be considered extensive, the optimal number of sheep on grasslands has been worked out to be about five individuals per hectare.
The benefits of this method are many. They are connected not only to restoring the natural wealth, but also to cultural and esthetic values. Traditions related to herding are a highly valued but forgotten element of the agricultural landscape in many regions of Poland.
It is best to work together with the local community...
The biggest problem in restoring grazing to grasslands is society's lack of interest, including farmers, for whom this type of activity has long been unprofitable. There is some hope in agricultural and environmental subsidies for farmers who utilize valuable natural habitats in an extensive manner and raise traditional breeds of livestock. Also, projects to protect xerothermic grasslands, such as ours, are a good opportunity to begin working together with the local community, without whose help efforts to protect many semi-natural habitats would fail. A significant proportion of xerothermic grasslands in Poland are privately owned, and encouraging owners to return to extensive farming practices on this type of land is the best guarantee for their appropriate and long term protection. Recently, a return to traditional farming methods, raising primitive animal breeds, producing local goods and living in harmony with the surrounding environment are becoming more valued. Greater interest is emerging for agrotourism, regional products and foods free of pesticides, antibiotics and the ever-present "chemicals".
Perhaps they should be purchased?
A last resort is the purchase of land whose owners who are not interested in returning to a previous form of use, even with external assistance. This land can then be donated to a park, environmental organization or other private individuals interested in maintaining it in a manner that protects this valuable habitat.
First you have to cut!
Because many xerothermic sites, including some of those incorporated into this planned project, are severely degraded - mainly due to advanced natural succession or afforestation, and also often do not have the appropriate conditions for grazing, it is necessary to remove the shrubs and encroaching trees. Despite appearances, planning the clearing of land is not a simple task. Due to the breeding season of birds, the best time to remove nuisance plants is winter. However, on the other hand, many of the species encroaching on the grasslands, such as blackthorn (Prunus spinosa), wolfberry (Lycium barbarum), raspberry (Rubus idaeus), blackberry (Rubus fruticosus) and black locust (Robinia pseudoacacia) are highly invasive and clearing them only in winter will not suffice. They will undoubtedly rebound in the spring with renewed strength from the rhizomes and seeds left behind that will be even better able to sprout given the increased exposure to light in the newly cleared area. In such cases, it is better to remove unwanted vegetation when it is flowering and fruiting. This is when plants are directing most of their energy to flower and fruit production, and to a greater extent succumb to physical damage (including cutting) than at other times during the growing season. But spring and summer are also the seasons when xerothermic grasslands come alive, and could be damaged during clearing activities. A controversial but effective method of removing invasive species is the application of chemical agents to confined areas, commonly used in horticulture for weed control. But an overly hasty application of this solution may be harmful to grassland plants. One of the safest methods is to apply chemical agents to cuts made in the trunks of invasive species during their growing phase or, for example, applying herbicides to freshly cut tree stumps.
It should be remembered, however, that shrub and forest assemblages, despite their threat to grasslands, can also have a special value to the natural environment. Thermophilous riparian forests on slopes or xero-thermophile oak woods where grasslands have developed also represent rare and vanishing habitat types in Europe. The presence of small woodlots and scrubland, hedgerows and individual trees has great significance in preserving a landscape's high level of biodiversity. The mosaic of grasslands, edges, thermophilous shrubs and clumps of trees are far more attractive to many thermophilous fauna than a uniform plain of grassland.
A good practice providing lasting effects is to use cutting together with grazing. The animals regularly put out to graze will systematically consume invasive species re-sprouting from roots and thus impede their development.
In many areas, simply removing invasive plants by cutting will not suffice for other reasons. The seeds of xerothermic species are very short-lived. If old blackthorn plants are removed from a former grassland, we can be sorely disappointed if we expect the soil's seed bank of xerothermic plants to naturally regenerate these species on its own. A supply of seeds from an external source, such as a well preserved grassland, will be required for those sites that are extremely isolated (such as those surrounded by forests) and degraded, with a very small number of desired species. An excellent method of transporting seeds, unconsciously used for centuries, is the rotational grazing of several grasslands by a herd of livestock, known as mobile pasturage. Wool is an excellent transporter for the sticky seeds of many grassland species, and quite a few others also travel in the digestive systems of the animals - some have even adapted to this type of dispersion, known as zoochores.
This is why mobile pasturage is needed!
This method is not widespread in Europe. It is used, however, in some of the countries bordering Poland, such as Germany. It will be used for the first time in Poland during the LIFE+ project.
This method is especially required for the extremely isolated xerothermic grassland project sites that are small, often quite far from farms or their owners are not interested in having them be used. This method was honed by the Naturalists' Club in 2008-2009 during another xerothermic grassland preservation project. It consists of transporting or, more rarely, driving herds of several dozen sheep from site to site during the entire growing season (the sheep return to sheds in the sheepfold for winter). Each grazed surface will be enclosed with a fence that is light and easily set up or dismantled, to be transported together with the herd to the next pasture. Part of the fencing and sheds will be left permanently. These will be located and constructed in such a manner as to provide wildlife with access to the grassland when it is not being used by livestock. The herd will be watched day and night by workers employed for the pasture season and volunteers. The livestock will be transported in a truck owned by the Naturalists' Club, and the shepherds will live in a trailer, transported together with the sheep from grassland to grassland. The animals will systematically be provided with potable water.
First, the animals will be put out to graze in the best preserved areas, and then in the more degraded ones - this will facilitate the spread of xerothermic species' seeds. We also plan to have only part of a grassland grazed (a different portion each year) so that the un-grazed plants can develop and put forth seeds without interference. This will also enable small animals less adapted to grazing practices to survive.
As a last resort, drastic measures must be applied...
In extreme cases, the only way to save a xerothermic grassland is to regenerate the most degraded patches. Such activities can be very helpful especially along the migration routes of species, where a restored grassland can reinstate or significantly facilitate migration between particular habitat patches. Xerothermic grasslands can be restored by sowing a set of seeds of the same species' assemblage found in less damaged areas or in another well-preserved area. It is important that the seeds originate from a site as close as possible to the one being restored. Another method is to transplant fragments of well-preserved grasslands. A several dozen centimeters long strip of turf with its accompanying rhizosphere is planted in the grassland to be restored. Such transplanted fragments become the source of desired species for the recreated habitat.
Populations of threatened species can be introduced by collecting their seeds, sprouting and growing seedlings in an ex situ setting, where conditions can be better controlled than in a natural setting, and then the young plants can be transplanted to the site from which the seeds were taken.
Education is also important!
Educational activities are often treated less seriously than "strong preservation measures". Publishing a folder or organizing a workshop does not often provide the immediate results seen after clearing a site, mowing or constructing a lock. But actually, the problem of environmental protection is in large part a problem of the lack of knowledge among owners, land managers, tourists, investors. Environmental education is the key to resolving this problem. A thorough understanding by society of the reasons and benefits of preserving nature will enable the full, professional and long-term protection of the natural environment surrounding us. It is most important, of course, to educate children and youth, because "What is absorbed during youth is remembered by age".