WEEDS 



We must notice, too, the European water cress, which, 

 winter and summer, chokes up our streams. It is inter- 

 esting to know that in this case, the Western world has 

 retaliated; the American pond-weed, Elodia, is much more 

 troublesome in the water ways of England than the water 

 cress is in ours. The water hyacinth, originally from 

 South America, which is actually ruining navigation in the 

 Florida rivers, is probably not suited to California streams. 



There are none of our native plants that, during the 

 growing season, deserve the name of weeds throughout the 

 state ; but there are some that are locally troublesome. 

 Sometimes they thrive because of strong underground parts; 

 this is true of the chilicothe, poison oak, bracken fern, 

 morning-glory, yerbamansa, blue-eyed grass, and some kinds 

 of lupines, Umbelliferse and lilies. Others are rapidly 

 growing annuals that can endure a drought better than 

 cultivated plants, and for this reason become specially 

 troublesome in dry years. The poppy, though a perennial, 

 should be counted here, because it matures so rapidly from 

 the seed. In the drier grain fields of the south in bad 

 seasons, it quite crowds out the grain, but farther north, 

 where the spring bloom is usually prevented by cultivation, 

 it bides its time, and comes up in full bloom in the autumn 

 months. All over the state, wherever it once held sway, 

 it is ready to repossess neglected spots. Other native 

 plants that still assert themselves, even in grain fields, are 

 the yellow forget-me-not, or Amsinckia, the Calandrinia, 

 a Portulaca with bright magenta flowers, the owl's clover, 

 or Orthocarpus, tidy-tips and some small Cruciferse. All 

 these native weeds seem likely to disappear as our state 

 grows older and the soil is more carefully tilled. Even now 

 they do comparatively little harm, and we are almost sorry 

 to think of the time when there will be no gay flowers 

 mingling with the growing grain. 



The weeds of the dry season naturally interfere much 



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