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changed. In a few days the hills show green with a carpet of 

 clover (Alfiluree) and flowers rather than of grass; the latter, 

 though in many places abundant, cannot be considered a feature 

 of the indigenous flora. 



Among the first to appear are Brassica nigra and B. campestris. 

 The former species is one of the greatest pests of cultivation, and 

 more detrimental to growing crops here than its better known 

 relative sinapis arvensis (wild mustard) is to those of the British 

 farmer. In the moist lauds and grain fields, where it has secured 

 a foothold, it grows most luxuriantly to a height of four to eight 

 feet or more, with stems as thick as a walking cane, and forming 

 with its interlacing branches thickets as impenetrable as brush- 

 wood. Popularly it is said to have been introduced at an early 

 date by the Spanish monks. Whether this is really so or not I 

 cannot authenticate, as the expression itself is very much akin 

 to that of " came over with the Conqueror," and is subject, I fear, 

 to like abuse. However introduced, its natural fertility, aided by 

 the blackbirds and finches, has spread it over the length and 

 breadth of the country. 



The plantaip, " the white man's foot," as the Indian calls it, 

 is but casually represented, but that more typical representative 

 of civilisation, the shepherd's purse, Capsella bursa jmstoris, is 

 here in abundance. In Britain one is too apt to forget that it is 

 an introduction there, having followed civilisation from the Medi- 

 terrean shores, and it seems but fitting it should continue the 

 Saxon's march in the peaceful settlement of the Western Con- 

 tin(mt. The common water cress, Nasttcrtium officinale, and 

 candytuft, Iberis amara, escaped from cultivation are well 

 established. The medicks are represented by M. denticulata and 

 M. saliva [Lucerne, or Alfalfa, as it is here called), and are two 

 of the most valuable fodder plants in California. M. denticulata 

 or burr clover, has by natui-al processes spread over the greater 

 part of the lower country, and not only aflbrds maintenance to 

 stock in its green state, but also when matured its ripe burrs 

 being greedily eaten by horses and sheep as they lie round the 

 withered remains of the parent stem. It has one serious draw- 

 back, however ; its burrs are the processes for perpetuation of 

 the species, and in their attempts to spread themselves they get 

 inextricably mixed among the coats of horses and sheep, and 

 nothing short of removing the hair or fleece will suffice to clear 



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