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HOW WEEDS SPREAD. 



Nature lias provided in au interesting and wonderful way for the 

 reproduction and dissemination of plants. A large number of common 

 Aveeds, 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 seetls 

 or fruits of many plants, especially those growing in or near water, are 



