Abstract
In the coffee zone of the town La Unión- Nariño, native or introduced trees are associated with the productive systems of the farms, mainly because they provide shade for coffee crops, where particular aspects such as species biodiversity and silvicultural management are unknown. With the aim of knowing the woody species of common use and the cultural importance, a semi structured survey was applied to 100 coffee growers who were selected at random and aleatorily distributed in three altitudinal ranges: (m.a.s.l.): I ( 1800). Species richness was determined for each chosen range; for diversity between ranges, the Jaccard Index (JI) and the Cultural Importance Index (CI) were used. The latter was determined by adding up the intensity of use (IU), frequency of citation (FC), and use value (UV). In the three altitude ranges evaluated, 59 tree species were found. These were distributed in 32 botanical families and 46 genera. The fabaceae family was the most representative, followed by rutaceae, myrtaceae and bignoniaceae; 45.8% of the species were introduced. Among the altitudinal ranges, a low degree similarity was found; ranks I and II shared 24 species, which is equivalent to 33.8% of their floristic composition. As for ranges I and III, they had an even lower degree of similarity: 24.2%; only 17 species were shared. The species I. densiflora had the highest percentage of CI, with 32.92%, followed by C. sinensis with 31.98%; then the species T. gigantea and P. americana with 30.49% and 26.27% respectively. These species were of great importance to coffee growers due to the positive impact they have on the family economy and their contribution to the environmental well-being of production systems.