An owl pellet is: Owls eat their food whole and since they don't have teeth, they can't chew their food. They use their strong and sharp beaks to rip their prey apart and then swallow large chunks whole. The owl slowly digests its meal by separating the softer materials (meat) from the harder material (bones). It then regurgitates the harder material along with indigestible items like feathers and fur in the form of a pellet.
(See what we found below)
Sumac Berries: These "berries" are really seeds covered with a thin coating of flavoring substance and hairs. Late Summer is the right time to harvest Sumac or as soon as they are ripe (dark purple in color) and before they have been rained on. This is when they will have the strongest flavor. The rain will wash off the sour flavor. Sumac berries make a great sour lemonade type drink or sumac-ade. This yummy drink is so easy to make: harvest 6-8 ripe "berry" clusters, taste them to make sure they have the sour flavor, put them in a pitcher and pour cold water over them. Let them sit in a cool place for awhile, taste drink to see if it is sour enough. When ready to drink, strain the drink through cheese cloth. This will remove all unwanted seeds and hairs. Some people add sugar, but we think it is great without. (I will remind you of this yummy drink when we actually do it later this season)
Just a note: sumac is related to cashews and mangoes, anyone allergic to those foods should avoid it and/or be very careful. Also, there is a poisonous Sumac (Toxicodendron vernix or Rhus vernix) but according to Wikipedia: "Poison sumac grows exclusively in very wet or flooded soils, usually in swampa and peat bogs, in the eastern United States and Canada."
Happy exploring and foraging!