What grass is characterized by its blue foliage?

The grass characterized by its blue foliage is Blue Oat Grass. This perennial grass is known for its attractive, arching blue-gray leaves that develop a distinct blue hue, particularly in sunny conditions. The color is a result of a waxy coating on the leaves, which helps to reflect sunlight and reduces water loss, making it well-suited to dry, well-drained soils.

In contrast, Japanese Blood Grass typically features striking red tips on its foliage rather than blue, while New Zealand Flax has long, sword-shaped leaves that are usually green or variegated but do not exhibit the blue coloring of Blue Oat Grass. Japanese Forest Grass, on the other hand, has green or variegated green leaves and is also not known for blue coloration. Thus, the distinctive blue color of Blue Oat Grass sets it apart as the correct answer.