25 June 2014

25 June 2014 – Fading Green

Green Oak Tortrix (Tortrix viridana)

Two weeks without rain have taken away the lush, green blanket on the fields behind Shandy Hall and the tall grasses in the pasture are starting to show signs of dusty yellow. Even the mighty oak trees carry a hint of shriveled brown on their leaves.

Fortunately, a flash of new green visited the garden this week.  It came in the form of a moth – a Green Oak Tortrix (Tortrix viridana) that made its appearance in our new actinic light trap.  It is a small moth with no flamboyant patterns on its wings.  Like many other species of the Tortricidae family, it was plainly bell-shaped and the bright green colour of its forewings make it instantly attractive.

Green Oak Tortrix (illustration)

The moth’s green color will not last long; green pigments always fade as the moth ages. Like the overwintered Autumn Green Carpet (Chloroclysta miata) this tortrix is fated to become unrecognizably grey come July.  In nature, green is perhaps the most transient color of all. Whether on moth wings or in oak leaves, it always fades fast.  Conversely, when rain falls the oak will recover its verdant cloak. Next year the viridana will flutter once more with its wings of jade.  In this regard, green is also a resilient color.

A new species for Shandy Hall : number 347.  (The leap in numbers will be explained…)

Post by Bowen Chang (UPenn)