Bilbo mourns that he is missing the pleasures of high summer in the Shire.  Picnic’s obsolete meaning is what I would call a pot-luck meal, in which all the guests bring something to share.  The word’s history may be French, it may be a sound-play, it may be German, but the German may be a borrowing from English – quite the enjoyable little mystery to entertain us as we dine outdoors.

• 04.003 and picnics.

“picnic, n., adj., and adv.” OED Online. Oxford University Press, March 2015. Web. 13 May 2015.