This section is from the book "A Manual Of Weeds", by Ada E. Georgia. Also available from Amazon: A Manual Of Weeds.
Introduced. Annual. Propagates by seeds.
Time of bloom: June to August.
Seed-time: July to September.
Range: Semi-arid lands of the Southwest, where seed-wheat from southern Europe has been sown. Occasional elsewhere but not troublesome as a weed. Habitat: Grain fields.
Fig. 116.- Great Celandine (Chelidonium ma-jus). X 1/4.
This is the pest which for centuries has made the wheat fields of Europe gorgeous with its color, and it is strange that it has not made greater headway in this country. Its seeds are most tenacious of life when in the soil.
Stems one to three feet high, slender, erect, many-branched, set with short, spreading hairs. The whole plant is filled with bitter, milky juices. Leaves all pin-natifid, the lobes lance-shaped, pointed, sharply toothed, the lower ones petioled, the upper ones smaller and sessile. Buds nodding, enclosed in two, or occasionally three, hairy sepals that fall away as the flower unfolds; these are very large, two to four inches broad; petals four to six, broader than long, of thin silken texture, bright scarlet with a dark blotch at the base; stamens many. Capsule top-shaped, the stigmatic disk at its apex usually ten-rayed, and with as many cells as rays, filled with very many small, brown seeds. (Fig. 116.)
Sow clean seed. Poppy seed is so very small that a good fanning mill should be able to remove it completely from all seeds of grass and grain. If the area infested is not too great to make the task impracticable, hand-pull the plants when the first bright bloom appears and burn them. Let none mature seed.
 
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