Nope. That's not a photoshop trick. Those really are blue trees. The University of Florida campus has turned some of its trees blue and it truly is amazingly beautiful. The artist, Konstantin Dimopolous, painted the trees blue as a social statement to raise awareness for the importance of the survival of trees. If you're interested, you can learn more about the artist and his project here.
Sweater: Loft / Shirt: Gap / Shorts: Loft / Shoes: Target / Handbag: Rebecca Minkoff Jewelry: Stella and Dot, David Yurman