Why I cannot find dendritic cells in blood smear?

According to many sources including Wikipedia, there are haematopoietic stem cell derived dendritic cells in the blood.

• figure 1 - haematopoietic cell lines - ref

Despite of this, when I examine a blood smear, I cannot find dendritic cells and I did not find any blood smear example on the internet, which depicts dendritic cells.

• figure 2 - blood smear cell lines - ref

Why is that?