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 October.
Seed-time: July to November.
Range: Eastern Quebec to Ontario, southward to Pennsylvania, Ohio, and Illinois.
Habitat: Fields, roadsides, and waste places.
An immigrant from Europe, abundant in its range, which is gradually extending. Its milky juice is exceedingly copious, and so acrid that it is used as a caustic to destroy warts. (Fig. 189.)
Stem stout, smooth, eight to fifteen inches tall, often branched from the base. Leaves obovate, rounded at tips, finely toothed, whorled and sessile at the base of the umbel, but those on the stalk scattering and tapered to a short petiole. Umbel compound, the rays usually five, first triply branching and then each branch forked; involucres bell-shaped, with unappendaged, round, stalked glands. Capsule smooth, with rounded lobes; seeds ovoid, reddish brown, the surface netted and pitted like a honeycomb.
Means of control the same as for Spotted Spurge.
 
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