Bořinka

Bořinka is a small but ecologically significant nature reserve in the Český Krumlov district of the South Bohemian Region, located roughly one kilometer west of the village of Holubov and about a kilometer south of Křemže, within the Křemže basin. The reserve forms part of the Blanský les Protected Landscape Area and is bordered on the north by the Křemžský stream. Administratively, it lies within the cadastral territories of Holubov and Chlum.

When was the reserve established?

Bořinka was officially declared a nature reserve on November 15, 1990, by decree of the Český Krumlov District National Committee, with legal effect from December 14, 1990. The protected area covers 8.93 hectares, with elevations ranging from 486 to 515 meters above sea level. Under the IUCN classification system, it falls into Category IV — an area managed primarily for habitat and species conservation.

What does the reserve protect?

The reserve safeguards a remnant of relict pine forest growing on serpentinite bedrock, together with a site of notable mineralogical significance. Serpentinite is a magnesium-rich rock that is toxic to most plant life, and Scots pine (Pinus sylvestris) is the only native tree species able to permanently withstand its harsh chemical effects. As a result, the dominant woodland type within the reserve is an open, sparse pine forest growing directly on serpentine substrate. The tree stand is even-aged, ranging between 70 and 90 years old.

The site falls within the Křemže serpentinite phytogeographical district (designated 37k). The herb layer includes sheep's fescue, various thyme species, and bellflowers. Among the most valuable and critically endangered species found here are the serpentine spleenwort — a fern that grows almost exclusively on serpentinite substrates — and the serpentine form of the Carthusian pink, which occurs sparsely and scattered throughout the reserve. Blueberry shrubs and ferns are also present in the understory.

What is the geological history of this site?

Cracks and fissures in the serpentinite rock were historically filled with magnesite, which was mined here on a small scale in the past. Traces of this mining activity remain visible today on the hillsides in the form of small excavations, sometimes referred to locally as "caves" — modest hollows left behind by the extraction of the mineral. This combination of unusual geology and the specialized vegetation it supports is what makes Bořinka an important mineralogical site within the region.

What else is notable about the surrounding area?

A small tributary stream runs through and near the reserve, showing pronounced signs of erosional activity that has shaped parts of its bed. A meadow lying just outside the reserve boundary displays notable botanical diversity of its own. Several footpaths cross the area, allowing visitors to walk through the site and observe the transition from open meadow to the sparse pine woodland growing on serpentine rock.

Frequently asked questions

Where exactly is the Bořinka nature reserve located? In the Český Krumlov district, about one kilometer west of Holubov and a kilometer south of Křemže, within the Blanský les Protected Landscape Area.

When was the reserve established? On November 15, 1990, with legal effect from December 14, 1990.

How large is the reserve? 8.93 hectares, at elevations between 486 and 515 meters above sea level.

What is the main conservation focus? A relict pine forest growing on serpentinite rock, along with its unique associated flora, and a mineralogical site connected to historical magnesite mining.

Which plant species found here are especially valuable? The serpentine spleenwort and the critically endangered serpentine form of the Carthusian pink, both restricted to serpentinite substrates.