sycamore
The two words you're looking for are "oak" and "earth." "Oak" is a type of tree, while "earth" refers to the planet we live on. Both words fit the criteria of starting with 'o,' having three letters, and five letters, respectively.
the letters when rearranged make the name of the CEDAR tree
Palm trees
Iroko.
peach pecan
Iroko.
Juniper
mocorrana
Conifer.
Acacia.
Dogwood?
There are several trees that all start with the letter 'p' and are five letters long. The name of one tree that starts with the letter 'p' and is five letters long is the peach tree.