Nigel Cattlin / Californian red scale insect (Aonidiella aurantii) scales on Orange (Citrus sinensis) leaf, zonal chlorosis present. Native to China. Sicily, Italy. October.

Nick Upton / Oranges (Citrus sinensis) fruits ripening, Argolis, Peloponnese, Greece, August 2013.

Nick Upton / Unripe and ripe Oranges (Citrus sinensis) hanging on a tree in an orange grove, Argolis, Peloponnese, Greece, August 2013.

Will Watson / Orange alga (Trentepohia sp.) growing on Wild cherry (Prunus avium) bark, Haughmond Wood, Shropshire, England, UK, March.

Juan Manuel Borrero / Orange (Citrus sinensis) tree flowers. Cultivated plant.

Ernie Janes / Sweet Chestnut (Castanea sativa) leaves in autumn, Norfolk, UK, November

Juan Manuel Borrero / Orange tree (Citrus aurantium sinensis) fruit and flowers, Spain.

Konrad Wothe / Sweet Orange (Citrus sinensis) fruit, Greece

Jose B. Ruiz / Sweet orange tree with fruit {Citrus aurantium sinensis} Valencia, Spain

Jose B. Ruiz / Orange tree flowers {Citrus aurantium sinensis} Spain

Jose B. Ruiz / Orange flowers {Citrus aurantium sinensis} Spain

Jose B. Ruiz / Oranges on tree {Citrus aurantium sinensis} Spain