360 
Report of the Botanist^of the 
Weeds Especially Troublesome to Field Crops. 
Red Root Amarantus retroflexus L. 
Ragweed Ambrosia artemisisefolia L. 
Pigweed Clienopodium album L. 
Barn-yard grass Panifcum Crus-galli L. 
Low Finger-grass Panicum glabrum Gaud. 
Lady's Thumb Polygonum persicaria L. 
Purslane Portulaca oleracea L. 
Foxtail grass Setaria glauca B. 
Pigeon grass Setaria v-iridis B. 
Could these nine kinds be banished from the country the warfare 
with weeds would be reduce^ one-half. Curiously enough, all of these 
but the ragweed are of foreign nativity, having emigrated to this 
country, and taken a' more vigorous hold of the soil than the native 
plants. A few additional kinds are very obnoxious now and then 
because, while they do not spring up everywhere like those mentioned, 
yet when once established they are with much difficulty eradicated; 
such are Canada thistles, quack grass, milkweed, sorrel, burdock, and 
ox-eye daisy. Other kinds, like shepherd's purse, chickweed, and 
speedwell, are very common in rich garden soil, but are easily 
suppressed. 
An answer to the query of what weeds and how many of a kind grow 
upon a definite area of cultivated soil was sought for in a different 
way. A square foot of surface soil, taken to a depth of three inches, 
December 11, from a plat (E 1 of the Station records) which had had 
clean culture, was transferred to the greenhouse. The same was done 
with soil from a plat (E 4 of the Station records) which had been 
allowed to run to weeds unchecked the previous season. Each was 
kept properly watered and remained undisturbed till the first of each 
succeeding month, when all germinations were counted and recorded, 
the plantlets removed, the ground thoroughly stirred (with one 
exception), and the soil again compacted, ready for the next month's 
growth. Soil was also taken from the same plats, in the same manner, 
only to one-half the depth, on April 14, and received like after treat- 
ment. The results of these trials are given in the accompanying table, 
in which the monocotyledonous plants, represented by the grasses, 
and the dicotyledonous plants, including all other sorts, are kept 
distinct. 
