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HOW WEEDS SPREAD. 
Nature has provided in an interesting and wonderful way for the 
reproduction and dissemination of plants. A large number of common 
weeds, such as the dandelion, sow thistle, wild lettuce, groundsels, white- 
top, ironweed, boneset, joe-pye weed, true thistles, produce seeds to which 
are attached light, fluffy, parachute-like structures which very materially 
facilitate their dispersal by the wind. Other weeds, such as yarrow, ox-eye 
Curled or Sour Dock. 
daisy and curled dock, are either very light, or have light membranous 
attachments. There is a group of weeds, including old witch grass, Russian 
thistle, tumbling pigweed and others, which have the characteristic of 
breaking off when mature at or near the surface of the ground, and, 
rolling hither and thither, far and wide, over the fields, discharge thousands 
of weed seeds as they go, in this way inoculating our fertile soils with 
crop-reducing weed pests. 
Another agency making for the spread of weeds, is water. The seeds 
or fruits of many plants, especially those growiug in or near water, are 
