Pigweed. Lamb's Quarters. Chenopodium album L. Seeds are likely to occur in either of three different guises dependent upon the degree of their ripeness or the amount of threshing to which they have been subjected. The figure shows these conditions admirably.

Seeds black, dull or somewhat glistening, gray if not pretty clean; nearly circular; somewhat lens-shaped, one side usually more nearly flattened than the other 1–1.4 mm. in diameter, the edge bluntly rounded, the more convex side bearing a curved groove leading from one side of the marginal protuberance to near the center of the face, surface finely uneven, often with a faintly evident radiating striation. Introduced from Europe. Very common in annual crops.

Fig 47. [Mexican Tea. Chenopodium ambrosioides] L.

Mexican Tea. Chenopodium ambrosioides L. Note remarks under last preceding description concerning different stages of cleaning. Seeds smooth, shining, reddish brown, to black, thickly double convex with scarcely a trace of a hem-like margin, circular, short kidney-shaped or ovate with a notch on the edge, .6-.8 mm. long. Introduced from tropical America. Not prominent.

Fig 48. [Jerusalem Oak. Chenopodium Botrys] L.

Jerusalem Oak. Chenopodium Botrys L. Concerning different states of cleaning, note remarks above under C. album.