Diagnose bare spot

[kk17203]

This is my first time raising chickens and I have noticed a bare spot on my Plymouth rock hens. They are about 3 to 4 weeks old I think. The one in the picture has the biggest spot. It is on both sides of the neck. Is it just a spot where feathers have not come in yet or something else?

 

[Poultry parent]

Chickens have feather tracts and featherless tracts, that spot is a featherless tract, and nothing to worry about