Glad2badad mentioned a very important point which is that half the battle of b/w is recognizing a suitable subject which the technique can best exploit. Skin on green is probably not the best, given the lack of tonal variety.
Focus is on the grass, not the feet.
Composition isn't bad, looks like you were going for a rule of thirds location with placing the feet there.
Obviously this is a mind-numbingly boring subject, but you probably knew that. Feet could be interesting I think, but probably not your own as you would need to find some other angle to shoot from to present them in a way that catches the viewer's interest.
And I can't wait for our summer so I can get out there in the sun and relax. I wonder if you lay on the grass, feet towards some kind of view and took the shot again ..... would be fun to try (never mind the neighbours would think you nutz)
It's put together well compositionally for a simple subject. It may be hard with skin tone and green grass to really show a full B/W tonal range (true white to true black). Maybe don't always need to cover the whole range? I'm not sure 100% on that myself. :P