LXXX 
MAN SPREADS WEEDS 
I SN'T IT ODD that man, as he pushes his commerce 
around the world, so multiplies his enemies that it 
seems sometimes as though they would destroy him! 
This danger has long been apparent in the case of in¬ 
sects. It is the ships of man that have borne one species 
of domestic cockroach, once known only in India, all 
around the world. The gipsy moth was brought to New 
England by man. The Japanese beetle came in on the 
roots of plants man brought from the Orient. The corn 
borer came over from Europe only a few years ago. 
But man does not stop with insects in multiplying his 
enemies. He does likewise with plants. He brings, from 
the ends of the earth, those weeds that he has fought 
through the centuries and starts them in his own fields. 
The weeds of the world largely have come to America 
in a strange manner. Many ships from many lands have 
come to these shores with cargoes and for cargoes. It has 
often happened that the cargoes they brought were 
packed with hay or straw. This waste has been thrown 
out wherever unpacking has taken place. Often it has 
carried the seeds of weeds that were enemies to man. 
Sometimes ships which have come to this country to 
take cargoes have contained ballast — earth or other 
waste. This ballast has been dumped on American 
shores. It has often carried weed seeds that have taken 
hold and done vast amounts of harm. 
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