BEAL ON MICHIGAN FLORA. 25 



WEEDS. NATIVE AND INTRODUCED. 



A new country is comparatively free from weeds, hiil as the years pass 

 by, one after another, weeds are introduced. Some of them are natives of 

 the neijiliborhoods in wliich they are found, hut most of them have been 

 introduced from other portions of our own country or fi'om f(u'eign coun- 

 tries. The farmer is not inclined to adopt Emerson's notion of a weed as 

 ^'a plant whose virtues have not yet been discovered," at least he doesn't 

 purpose trying to find a use for them. The seeds of most weeds find their 

 way onto a farm nicely mixed with seeds of grasses, grains and cloviis, 

 which are drilled in or sowed broadcast on fertile soil, where they are 

 afforded an excellent o])portunity to grow and multi])ly. In some in- 

 stances weeds are inti'oduccd as a jiart of the packing or straw employed 

 to protect castings, marble, crockery or fruit trees. Such foi-eign j)acking 

 should always be burned at once. 



By these processes the older the country the more trouljlesome weeds ii 

 will have, as every new intruder usually comes t-o aiax. In most cases a 

 weed becomes well established before it is discovered and the inquiry 

 comes: "What is it, and how can I get rid of it?" 



Weeds are likely to become most troublesome, where farmers are 

 slovenly and where they are not thorough in cultivating throughout the 

 season the so-called "hoed crops." In regions where "hoed crops" are 

 seldom raised or only raised in small quantity, certain weeds are likely to 

 prove very annoying. The majority of our weeds have been introduced 

 from Europe, as will be seen by a comparison of the two lists which 

 follow : 



LIST OF WEEDS INTRODUCED UROM EUROPE AND ASIA. 



The List includes at least seventy-eight species, and very likely more. 

 Abutilon Abutilon (L.) Rusby. Velvet Leaf. 

 (Abutilon Avicennce Gaertn.) 

 Agrostemraa Githago L. Corn Cockle. 

 (Lychnis Gitlwgo Scop.) 

 Alsine media Iv. Common Clickweed. 

 iStellaria media Cyr.) 



Alyssum alyssoides (L.) Gouan. Yellow Alyssum. 

 (Alyssum cahjcinum L.) 

 Amaranthus hybridus L. Slender Pigweed. 

 (Amaranthus chJorostachys Willd.) 

 Amaranthus retroflexus L. Rough Pigweed. 

 Anthemis Cotula L. May-weed. 

 Arctium Lappa L. Burdock. 

 Brassica arvensis (L.) B. S. P. Charlock. 

 (Brassica Si7iapistru7n Boiss.) 

 Brassica juncea (L.) Cosson. Indian Mustard. 

 Brassica nigra (L.) Koch. Black Mustard. 

 Bromus hordeaceus L. Soft-Chess. 

 {Bromus mollis L.) 

 Bromus racemosus L. Upright-Chess. 

 Bromus secalinus L. Cheat. Chess. 

 Bursa Bursa-pastoris (L.) Britton. Shepherd's Purse. 

 (Capsella Bursa-pastoris Medic.) 



Camelina microcarpa Andrz. SmaU-fruited False-flax. 

 Camelina sativa (L.) Crantz. False-flax. 

 Carduus arvensis (L.) Robs. Canada Thistle. 

 (Cnicus arvensis Hoffm.) 



Carduus lanceolatus L. Common or Bull Thistle. 

 (Cnictcs lanceolatus Willd.) 

 4 



