The Forest Army are an army of anthropomorphic living trees that appear in the movie Maleficent.
The Tree Warriors protect the Moors and serve under Maleficent's command. When the forest kingdom was under threat of a army from the human kingdom, Maleficent became the land's protector and summoned her army of tree creatures to fight King Henry's army and seemingly over-powered them but failed to protect Maleficent when King Stefan betrayed her and took her wings.
Two Border Guards
The Two Border Guards are humanoid tree looking giants made of roots and greenery with faces that merely look like evil skulls and one of them named Balthazar. When in battle they are known to be strong and fearless and even the creatures of the Moors fear them. They carry tree like spears and masses and ride warthog looking creatures that are like them made of roots and greenery.
They also appear to serve as Maleficent's loyal guards as two of them stand beside her after she claims her throne making herself Queen of the Moors.
At the moment there isn't much about the Forest Dragons Only that they appear to be giant snake like beasts in appearance made of roots and greenery with beak like snouts and sharp teeth. It is possible they live beneath the earth since they emerge from the ground when summoned by Maleficent to battle the invading human army led by King Henry.