_ 178 Figuring against Weeds. 
single season or enough to thoroughly stock a country with this 
pest. A student made a careful estimate of the seeding capacity 
of a single plant of the small veronica, called niclace speedwell, and 
found that the number of seeds was 186,292. These figures help 
to force home the thought that weeds, and especially these sorts 
which are dependent upon seeds for their continuation, are exceed- 
ingly prolific, and also the importance of keeping such pests from 
maturing their offspring. 
When asked to select the most offensive among the worst weeds 
the task becomes an exceedingly difficult one. Among the annuals, 
especially in gardens, the purslane or “ pusley ” perhaps takes the 
lead. In striking contrast with the prostrate purslane is the shrub- 
like Jamestown weed or stramoniums, sometimes called jimson weed. 
The rank herbage and heavy order of these coarse weeds, as well as 
their larger size, make them conspicuous and disagreeable. The 
pig-weeds and the closely related tumble-weed are common coarse 
intruders into the tilled ground. 
Of the biennial the most to be dreaded are the carrot and the 
fleabane, both of which, in their own widely different way, can do 
much to render the life of the farmer vexatious. 
The worst foreign perennial, at least the one with the most 
meanness in its make up, is the Canadathistle. At present it is but 
little known in many parts of the State ; but it spreads rapidly by 
means of its airy floats which bear the light seed for long distances, 
and when once established in the soil it holds its place with an 
almost undying grip. The long perennial roots strike Iowa deep 
into the soil while the prickly herbage defies the attacks of foraging 
animals. The curled-leaf dock also takes a firm hold and is eradi- 
cated only by being dug up by the roots and hung in the sun Or 
burned. Of the native perennials there are various sorts of coarse 
thistles and the celebrated quack or quick-grass. This last 15 4 
remarkable instance of propagation by undergrown stems. p lowing 
and harrowing only aids in the spread of this pest. Each piece of 
wiry stem when given any sort of a chance will grow and develop 
the weed. 
As a rule the weeds of all classes should never be permitted to 
mature their seed. With annuals this is a quick and effective 
means of eradication. The biennials will perish at the end of the 
