merous as
the sands upon the seashore."

Perhaps the most notable thing about the weeds that have come to us
from the Old World, when compared with our native species, is their
persistence, not to say pugnacity. They fight for the soil; they
plant colonies here and there, and will not be rooted out. Our native
weeds are for the most part shy and harmless, and retreat before
cultivation, but the European outlaws follow man like vermin; they
hang to his coat-skirts, his sheep transport them in their wool, his
cow and horse in tail and mane. As I have before said, it is as with
the rats and mice. The American rat is in the woods and is rarely seen
even by woodmen, and the native mouse barely hovers upon the outskirts
of civilization; while the Old World species defy our traps and our
poison, and have usurped the land. So with the weeds. Take the
thistle, for instance,--the common and abundant one everywhere, in
fields and along highways, is the European species; while the native
thistles, swamp thistle, pasture thistle, etc., are much more shy, and
are not at all troublesome. The Canada thistle, too, which came to us
by way of Canada,--what a pest, what a usurper, what a defier of the
plow and the harrow! I know of but one effectual way to treat it,--put
on a pair of buckskin gloves, and pull up every plant that shows
itself; this will effect a radical cure in two summers. Of course the
plow or the scythe, if not allowed to rest more than a month at a
time, will finally conquer it.

Or take the common St. John's-wort,--how has it established itself in
our fields and become a most pernicious weed, very difficult to
extirpate; while the native species are quite rare, and seldom or
never invade cultivated fields, being found mostly in wet and rocky
waste places. Of Old World origin, too, is the curled-leaf dock that
is so annoying about one's garden and home meadows, its long tapering
root clinging to the soil with such tenacity that I have pulled upon
it till I could see stars without budging it; it has more lives than a
cat, making a shift to live when pulled up and laid on top of the
ground in the burning summer sun. Our native docks are mostly found in
swamps, or near them, and are harmless.

Purslane--commonly called "pusley," and which has given rise to the
saying, "as mean as pusley"--of course is not American. A good sample
of our native purslane is the claytonia, or spring beauty, a shy,
delicate plant that opens