Balder, H., Strauch, K.H., & Backhaus, G.F. 2003 Pests of ornamental plants in streets and public gardens of Lleida (Spain).. Second International Symposium on plant health in urban horticulture. Biologische Bundesanstalt fur Land- und Forstwirtschaft Berlin

Notes: [Mitteilungen aus der Biologischen Bundesanstalt fur Land- und Forstwirtschaft, Heft 394. Berlin, Germany, 27-29 August, 2003.] Field and laboratory studies were conducted in Lleida, Spain, from 2001 to 2002, to identify the pest affecting ornamental plants in this town, determine the relative abundance and phenology of the pest species and the presence of beneficial fauna related to them and evaluate the different strategies currently used to control these pests. Several plants of the most abundant tree and shrub species were visually inspected. Infested plant parts were collected and brought pest species and their predators were identified. Plant pests were recorded in 80 different plant species. The number of plant-pest associations was 196 and 173 in 2001 and 2002, respectively. The most abundant pest group was Aphididae (50%), which caused extensive damage on Acer, Catalpa, Cedrus, Hibiscus, Lagerstroemia, Populus, Prunus, Quercus, Robinia, Sophora and Tilia trees. Coccinelids were the most abundant aphid predators and Lysiphlebus testaceipes was the most common parasitoid species. Coccoidea had approximately 20% of the plant-pest associations. Palaeococcus fuscipennis heavily damaged Pinus sp. during 2001 but the occurrence of natural enemies was very high and a possible cause of the pest decline in 2002. Pseudaulacaspis pentagona, an emerging pest in Lleida, infested Morus, Sophora, Firmiana, Catalpa and Melia trees. Eotetranychus tiliarium.