"Once established, expansion of local colonies may result in extensive smothering of native communities, altering their structure and composition. Ledge, crevice, and scree communities may be affected, as well as a range of calcareous grassland communities. Root systems are highly pervasive, often penetrating deeply into crevices in the bedrock. Moreover, C. horizontalis is known for causing contact dermatitis and might potentially become problematic in case of increased occurrence." 
"Various species of the genus Cotoneaster are used as cooling, laxative, aperients, astringent and expectorant agents. Some are also used in the treatment of eye diseases, abdominal pain, piles, bronchitis, itch, thirst, leucoderma, fevers and wounds. Among the largest genera in the family is the ornamentally important genus Cotoneaster with about 40 species of woody plants." 
"C. horizontalis is prostrated, has a rapid lateral expansion and can grow on very thin soils or rocks and on steep slopes. Those characteristics, as well as its red color in the fall, make the species of particular interest for horticulture, as a cover species for walls or embankments. In a recent survey, we found that 52% of the plant nurseries (n = 102) sell C. horizontalis in southern Belgium." 
 Khan, S., Wang, Z., Wang, R., & Zhang, L. (2014). Horizontoates A–C: New cholinesterase inhibitors from Cotoneaster horizontalis. Phytochemistry Letters, 10, 204-208.
 Piqueray, J., Mahy, G., & Vanderhoeven, S. (2008). Naturalization and impact of a horticultural species, Cotoneaster horizontalis (Rosaceae) in biodiversity hotspots in Belgium. Belgian Journal of Botany, 113-124.