My thoughts only... and my husband did clean room decon and certification.
Only use wood from trees that are not treated (such as fertilized tree in your yard). But go for walk in woods away from where cars drive (avoid the fumes).
Easiest is to put them in oven for 30 minutes to hour at 175 to 200. Less time for thinner twig, longer for thicker perch size. Low and slow
You can also boil, but risk splitting wood.
We are in process of making a bird playstand and the center post is to big to heat, so went option of out in freezing cold for few days then soaked and cleaned with grapefruit seed extract.
Good luck!! Do a search to find bird safe trees, most important!!
No not random picked wood from outside. Just untreated pine wood. I'm not trying to make perches. Just some shapes and cubes and watnot from untreated pine.
Disinfection is to prevent giving your birds a disease. If you harvest the wood during times when outside birds are very active you could easily transmit diseases and bugs. I prefer to cut fresh in the winter then place in front if gas fireplace to dry.