Photo 1. The feathery awn of feather grass (Photo by Patrik Krstinić)
GRASSES AND THE BORA WIND ON THE ISLANDS OF KVARNER BAY
Grasses are the major building blocks of diverse grassland plant communities found on the Kvarner Bay islands. The general shape of grasses is more or less the same – as a rule, they have jointed stems. Growing in clumps, many grass species recover easily from frequent mowing or grazing. Despite these similarities, grasses display an exceptionally rich variety of shapes and ecological adaptations.
In addition to being resistant to grazing and mowing, some grass species are very resistant to intense winds. The bora wind is a strong wind of the Kvarner Bay islands, and its impact on vegetation is evident in the way it bends tree trunks and shapes the crowns of trees and bushes.
Narrow-leaved moor grass (Sesleria juncifolia) and feather grass (Stipa spp.) are examples of grasses perfectly adapted to the intense and frequent buffeting of the bora wind.
Narrow-leaved moor grass is very wide-spread on the hinterland mountains of Kvarner Bay, where it grows as a kind of “mountain” grass species in bora wind-exposed habitats, known locally as “burnjaci”. This resistant grass can also be found on the northern sides of some Kvarner Bay islands, in particular on the islands of Krk, Prvić and Cres. By all indications, the grass populations on these islands are relicts from a colder period of the geological past, when the bora wind was perhaps even more frequent and narrow-leaved moor grass was much more wide-spread in that region.
The leaves of narrow-leaved moor grass and other bora-resistant grasses are bitter, tough and, as a rule, narrow. Growing in clumps, the leaves are usually bent in the direction of the bora wind (Photo 2). In addition to having leaves that are rolled inward to shield the pores from excessive loss of water through transpiration, feather grass also has long, feathery awns that sway picturesquely in the wind (Photo 1).
Locals like to gather the feathery awns as a decoration for their homes. The shape of the awn, in fact, makes it easier for the grass to spread its seeds in the wind. Anemochory, the dispersal of seeds by wind, is quite wide-spread among plant life.