Southern River Struma Valley

Southern River Strouma Valley

The River Strouma Valley is situated in Southwestern Bulgaria and comprises a narrow strip of land along the rivers Strouma and Stroumeshnitsa. The climate is transitional sub-Mediterranean, with hot and dry summers. The basal rock is variable – from siliceous to limestone and sandstone. The vegetation is strongly influenced by human activities and is rich of southern plant species. Small parts of the area are selected as Important Plant Areas.

Southern Strouma Valley

© Boris Assyov

A few Balkan endemics may be seen in this area, namely Achillea clypeolata, Alkanna primuliflora, Anchusa macedonica, A. spruneri, Campanula scutellata, Centaurea immanuelis-loewii, Colchicum bivonae, Delphinium balcanicum, Dianthus gracilis, D. pelviformis, Knautia macedonica, Sempervivum ciliosum, Silene graeca, Stachys leucoglossa, Thymus atticus, Verbascum pseudonobile, and V. rorripifolium. One remarkable nearly endemic for the Balkans plant must also be mentioned here, namely Astragalus physocalyx.

Some orchids are present, especially Anacamptis pyramidalis, Ophrys cornuta, O. mammosa, Orchis morio, O. purpurea, and O. tridentata. Here is one of the two known Bulgarian localities of Liparis loeselii, a species that is considered extinct in this country nowadays.

Other rare or threatened species are Aegilops geniculata, Alkanna tinctoria, Amygdalus delipavlovii, Anemone pavonina, Crassula tillaea, Dracunculus vulgaris, Echinophora sibthorpiana, Ephedra fragilis, Erianthus ravennae, Goniolimon collinum, Juniperus excelsa, Ononis adenotricha, Onosma heterophylla, Osmunda regalis, Platanus orientalis, Quercus coccifera, Romulea bulbocodium, Sedum aetnense, Thelypteris thelypteroides, and Valeriana dioscoridis.

Further notable species are Acer monspessulanum, Achillea coarctata, Alcea heldreichii, Anemone apennina, Arceutobium oxycedri, Asparagus acutifolius, Aurinia saxatilis, Bituminaria bituminosa, Cardamine graeca, Carduus thoermeri, Carpinus orientalis, Carthamus dentatus, C. lanatus, Centaurea salonitana, Cistus incanus, Cnicus benedictus, Colutea arborescens, Coronilla emerus, Cyclamen hederifolium, Digitalis lanata, Euphorbia myrsinites, Fraxinus ornus, Hypecoum imberbe, Jasminum fruticans, Juniperus excelsa, Knautia orientalis, Legousia speculum-veneris, Linaria pelisseriana, Lotus aegaeus, Lychnis coronaria, Lysimachia atropurpurea, Neatostema apulum, Nigella damascena, Nonea atra, Onobrychis aequidentata, O. caput-gali, Onopordum illyricum, Onosma heterophylla, Paliurus spina-christi, Periploca graeca, Pistacia terebinthus, Plumbago europaea, Pyrus amigdaliformis, Salvia sclarea, Saxifraga graeca, Scilla autumnalis, Scolymus hispanicus, Scutellaria orientalis, Seseli rigidum, Silene conica, Silybum marianum, Teucrium polium, Tribulus terrestris, Trifolium cherleri, T. subterraneum, Umbilicus erectus, Xeranthemum annuum, and Ziziphora capitata.