Dogs cannot see the color green as humans do; it appears as a shade of yellow or gray to them.

Because dogs lack the cone that detects green wavelengths, green colors do not stand out distinctly in their vision. Instead, greens are perceived as muted yellows or grays depending on lighting and surrounding colors. This means that a lush green lawn looks quite different to a dog, more like a neutral or yellowish surface than a vivid green patch.