Udin boršt flora
Favourable ecological conditions enabled Udin boršt to be covered with forest in the majority of its area. Nowadays these serried forests, which lie in prealpine phytogeographical region, include almost 1,300 ha or almost 80% of the whole area. Therefore Udin boršt is one of the biggest areas of lowland forests in central Slovenia.
In the 17th century oak and hornbeam trees predominated, however, this changed drastically later on. Due to cutting down trees in particular areas and collecting litter, the growing sites have become impoverished in the last few centuries in Udin boršt. Washed out pseudogley soil, luvisol on conglomerate, which has poor nourishment and humus value, is above the conglomerate rock. This kind of soil combined with acid soil resulted in pine trees in the majority of Udin boršt and blueberry bush (combination of red pine and blueberry) in the undergrowth. There are also a lot of chestnut trees and spruce trees planted there on purpose. There are communities of white fir with round leaved bedstraw and beech tree with deer fern, sessile oak and common hornbeam with Christmas rose. Fern and blueberry predominate in the undergrowth.
These forest communities grow only on the forest brink and in stream valleys. The diversity is much higher in those areas.
In Udin boršt undergrowth and other habitat types such as wetlands, marshes and caves there is a variety of other plant species. At the entrance of Arneševa luknja, due to special ecological conditions, thrive certain herbaceous perennials such as Geraniaceae, bitter cress (Cardamine amara) and moss, e.g. common liverwort (Marchantia polymorpha). Quite the opposite is the marshy area south of Strahinj, soaked with springs flowing from rock shelters and caves. In the marshy springs in peat moss grow round-leaved sundew and menyanthes. There is also abundance of horsetail, buttercup, guelder rose, lily of the valley, heather and orchids.
Along the conglomerate wall above the area called Štucelj, which is above Naklo, there is a site of thermophile vegetation. Grassland edges, which were mown for litter a few decades ago, are now slowly getting overgrown by forest.
Kriva jelka forest reserve
Kriva jelka forest reserve with 10.22 ha area lies approximately 4 km east of Golnik above Kranj. It is one of the few forests with lowland jungle characteristics in which traces of man’s interference can be seen (traction and cutting down trees). Since 1979 this part of the forest has been intentionally left alone for natural processes to work its ways. All steps of evolution can be seen here from young and mature trees to dead ones. It enables forest ecosystem to be stable and resistant to stochastic events which unexpectedly change the living conditions for growth and evolution of forest and strengthen its self-preservation skills.
Trees that are decomposing play an especially important role because they provide constant and slow influx of nourishment for all the other species.
Kriva jelka forest reserve is like a classroom in nature where we can explore evolution of flora and fauna and their co-dependence. Furthermore, we can learn what maintains the forest’s vitality which enables constant adjustment and self-preservation. Nature has created a permanent, self-preserving lowland jungle forest, capable of self-recovery which, as opposed to cultivated forests, does not need constant help. The following trees grow on the semi-deep acid brown ground consisting of sandstone and slate: spruce (35 %), red pine (19 %), fir (14 %), beech (13 %), oak (11 %), chestnut (5 %), mountain maple, common ash, laburnum, willow and the rest (3 %).
A big forest hand has been greeting and offering symbiosis to visitors since 2012 by the western access into the reserve. Information boards have all the important data about the reserve and rules that visitors have to follow.
Udin boršt fauna
Udin boršt fauna is varied and diverse due to its numerous diverse habitats in this area; apart from forest caves there are underground caves, wetlands and streams. The most common non-vertebrate fauna consists of molluscs (snails), arachnids, spiders, millipedes and insects (beetles, butterflies), and the most common vertebrate fauna are amphibians (frogs, toads), mammals (deer, brown hare, martens: beech marten, ermine, least weasel, skunk, badger, fox, hedgehog, mole, mice, shrew mice, vole etc.), birds (warbler, thrush, finch, shrike, bunting, pigeon, wild hen, raven, bird of prey, owl, etc.)
Changes in forest communities and extensive hunting in the past have influenced surface fauna. Mostly deer and occasional wild boar and stag can be seen in Udin boršt and on its brinks. The most common beasts are badger, marten and fox. Skunks have also been seen. After a wave of rabies, the number of foxes has increased. Number of martens, especially beech marten, which found its habitat in serried settlements, is also increasing. Among the protected mammal species, squirrel, ermine, skunk and occasionally a wild cat found their habitat in the area. A few years ago an otter was seen in Golnišnica stream and was last detected in a stream by Bistra river.
The number of brown hares is severely endangered mostly because of influences of intensive farming. Wild and forest hen is also endangered while the number of partridges changes from year to year.
The number of forest partridges has dropped significantly; however, there are more wood grouses. Other data suggests that hunters saw both birds in the past which is not the case anymore.
The most common birds of prey are buzzard and goshawk and in time of migrations peregrine, harrier, kestrel and some other raptors. Marshy grassland is important for its nesting place for marsh bird. There are many singing birds as well and the singing of a finch, blackcap, golden oriole, gold crest, and others residing around the forest brink, can be heard. Other forest birds typical for this area have their habitat here as well, such as black woodpecker, great spotted woodpecker, treecreepers, numerous tits, sparrowhawk, and brown owl.
Many dragonflies and even crayfish reside on the surface. Some autochthonous fish such as trout, barbel and cottids live in streams. Hunters dammed Želinj stream in the 60s of the 20th century. This is how a pond was formed where they introduced the autochthonous duck species called the mallard. A few years later, fishermen built another dam and created another small lake where they introduced and started to breed non-autochthonous species such as carp, tench, chub, grass carp, roach and common rudd. Near water you can see a grass snake and aesculapian snake and many frogs in the nearby puddles and ponds. A very typical and common dweller is salamander. Streams are very suitable for laying its eggs which evolve into larvae.
