Answer: Maybe sometimes, but it is often prohibited and can be unsafe. 

What do the regulations say?

Some tree planters like to listen to music or podcasts while they are working. It can be used for motivation or to break the monotony of work. However, wearing headphones or playing music loudly can also create hazards for workers if they are unable to hear emergency calls or remain aware of their surroundings.  Section 4.25 of the BC Occupational Health and Safety Regulation prohibits workers from engaging in any activity that may create or constitute a hazard to themselves or to any other person. If a worker is listening to music while working, this may constitute a hazard by impairing their ability to be aware of hazards such as wildlife or falling trees, and they may be unable to hear other workers calling for help or alerting them of danger.

What does your employer say?

Most employers have rules that restrict the use of headphones. Some allow workers to use a wireless speaker that they carry in their back planting bag. The benefit of the speaker is that it can prevent workers from startling wildlife and can be shared with other workers. The drawback is that it can be shared with other workers, and musical tastes can vary. Regardless of what type of music a person enjoys, the volume must also be kept low enough to permit the worker to remain aware of their surroundings.

What might you be missing?

Music may also mask subtle sounds that can assist workers, such as specific sounds your shovel makes as it comes into contact with different types of soil, thus telling you whether or not you found a suitable planting microsite.   Listening to music may also prevent workers from detecting a wasp nest and increase their risk of an unpleasant sting.