PlantFiles: Field Penny Cress
Thlaspi arvense

Quite common in Russia. Grows as weed on the sown areas, waste plots of land, sides of the roads, meadows.

I thought I would add some info on this plant since it hasn't been commented on yet.

Here is some info on Field Pennycress from "The Encyclopedia of Edible Wild Plants of North America: Nature's Green Feast" by Francois Couplan, Ph.D.

"The leaves of these plants are edible raw, but they are pungent and often bitter. It is usually preferable to use them as a condiment or to cook them, possibly in a change of water. The very young leaves are best. Those of the Eurasian T. arvense have a pleasant, although somewhat bitter taste. They were widely utilized, and this species has been cultivated as a vegetable, especially in Asia.

Its seeds can be used as a mustard-like condiment. They contain the same glucoside (sinigroside) as black mustard (Brassica nigra), as well as a fixed oil which was used for burning in lamps."

Here's more info according to "Edible Wild Plants of Eastern North America" by Fernald & Kinsey.

"The young leaves are edible, tasting somewhat mustard-like, with a suggestion of onion. The seeds can be eaten as a mustard-like condiment."

According to a third source, "Edible Wild Plants: Eastern/Central North America" by Lee Allen Peterson, the young leaves can be added to salads or prepared like spinach.