Here are a pair of newer picture books that celebrate our connection with nature and invite young ones to head out and explore:

Forest Song by Kirsten Hall & Evan Turk (9780593480366)
Explore poetry and nature together in this gorgeous picture book. Hall has written a poem that pays clever homage to great poets such as Robert Frost, Mary Oliver, and Edgar Allen Poe. The illustrations by award-winning Turk are rich with color, riotous with swirls and an invitation into the drama of the forest. Combined with the lyrical language, this book is a celebration of the woods.
Appropriate for ages 4-8 and can be used with older children to explore poetry. Reviewed from library copy.

A Pocket Full of Rocks by Kristin Mahoney, illustrated by E.B. Goodale (9780593428542)
Fill your pockets with a young child as the seasons change. From rocks in winter to petals in spring, shells in summer and acorns in fall. Layer them all together in a glass jar to see your year. Reach for them in your pocket when you need some comfort. This picture book celebrates seasons through the senses, touching each item, listening to them and pretending with them too. The illustrations are marvelously simple and yet filled with a magic of fairies and nature.
Appropriate for ages 3-7. Reviewed from library copy.