Paper has auto-ignition temperature higher than 420°F, I would expect wood to be at least same as paper or higher
Edit: ok, I found a link to the study that says the wood will ignite at a lower temperature but will require some time (maybe the same is true for paper, now I’m not sure, it definitely chars in the oven)
The problem with using an oven as a reference is that the majority of ovens have relatively large temperature swings. You might set it to 420F, but the temperature swing can be anywhere from 10-60F, so it’s possible to hit 480F which is well over the autoignition temp.
Paper has auto-ignition temperature higher than 420°F, I would expect wood to be at least same as paper or higher
Edit: ok, I found a link to the study that says the wood will ignite at a lower temperature but will require some time (maybe the same is true for paper, now I’m not sure, it definitely chars in the oven)
The problem with using an oven as a reference is that the majority of ovens have relatively large temperature swings. You might set it to 420F, but the temperature swing can be anywhere from 10-60F, so it’s possible to hit 480F which is well over the autoignition temp.