La vegetación en bordes de rutas del Alto Valle de Río Negro, Argentina

the objective of this job was the study of the ruderal vegetation in adjacent areas to the 22nd national route. there were established the floristic composition, present communities and their development degree. the study was carried out in a section of 100 km of length, between the places of chichinales and fernandez oro, rio negro province, argentina. the samples were made according the braun blanquet methodology during the 2004 - 2005 period. the taxonomic study allowed to establish ten associations distributed in four vegetation classes. in the slope area (b) the present communities, that show higher antropic intervention, were cynodetum dactyli and distichletum spicatae. in the hollow zone (c), with higher humidity and salts content, it settled down baccharidetum salicifoliae and psiletum spartioideae among others.