Unlike rabbits or deer, squirrels cannot digest cellulose and must rely on foods rich in protein, carbohydrates, and fat
In temperate regions early spring is the hardest time of year for squirrels, since buried nuts begin to sprout
and are no longer available for the squirrel to eat, and new food sources have not become available yet
 

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During these times squirrels rely heavily on the buds of trees. Squirrels' diet consists primarily of a wide variety of plant food,
including nuts, seeds, conifer cones, fruits, fungi and green vegetation. However some squirrels also consume meat,
especially when faced with hunger. Squirrels have been known to eat insects, eggs, small birds, young snakes and smaller rodents.
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