Yes, It is Douglas Fir... the whole house is done in fir although a lot of it is stained as walnut.
My local supplier was asking $300/ sheet for 3/4" ply and $200 for 1/4"...a bit insane! Especially as Fir is very local to me. So other than the backs and drawer panels, it is all solid wood (much of it recycled from old government buildings that were either torn down or renovated)