Rowan is attested from the 1520s in the sense "fruit of the service tree", adopted via French "sorbe" from Latin "sorbum" "service-berry". "Sorbus domestica" is also known as "whitty pear", the adjective whitty meaning "pinnate". The name "mountain-ash" for "Sorbus domestica" is due to a superficial similarity of the rowan leaves to those of the ash, not to be confused in "Fraxinus ornus", a true ash that is also known as "mountain ash". "Sorbus torminalis" is also known as "chequer tree"; its fruits, formerly used to flavour beer, are called "chequers", perhaps from the spotted pattern of the fruit. The name
Aphis pomi "A. pomi", especially at high temperatures. Besides occurring on apple ("Malus domestica"), "Aphis pomi" infests other plants in the family Rosaceae including pear ("Pyrus communis "), hawthorn ("Crataegus monogyna"), medlar ("Mespilus germanica"), quince ("Cydonia oblonga"), mountain ash ("Sorbus aucuparia"), rose ("Rosa") and spiraea ("Spiraea"). It is an autoecious species, completing its life cycle on a single host species. Overwintering eggs hatch in spring and the aphids colonise the growing tips of the shoots causing the edges of the leaves to curl. These aphids are all viviparous females and give birth to other wingless aphids by parthenogenesis. In June some winged