214 REPORT OF THE DEPARTMENT OF BOTANY OF THE 
WEEDS. 
All writers on alfalfa culture agree that weeds are one of the 
chief hindrances in starting alfalfa. This applies in New York quite 
as much as it does elsewhere. Many of the failures with alfalfa ia 
this State are due to sowing on foul land. Practically all of the 
trouble with weeds comes during the first season. Alfalfa seedlings 
can not successfully compete with weeds; but after the first year the 
alfalfa plants are-able to hold their own against even the most ag- 
gressive weeds. In established fields weeds are rarely troublesome. 
In New York, it is doubtful if weeds ever run out alfalfa after 
the first season. When old alfalfa fields become overrun with weeds 
and grass it is likely that the stand of alfalfa has been thinned by 
heaving and other forms of winter injury, not by the competition of 
the weeds. 
The weeds which are most likely to cause trouble in newly-seeded 
alfalfa fields in New York are crab grass (Digitaria sangwinalis), 
ereen foxtail (Setaria viridis), yellow foxtail (Setaria glauca), 
lamb’s quarters (Chenopodium album), pigweed (Amaranthus retro- 
flexus), ragweed (Ambrosia artemisufolia), and barnyard grass 
(Echinochloa crusgalli). Charlock (Brassica arvensis) and quack 
grass (Agropyron repens), also, are troublesome, but occur less 
frequently. It is folly to sow alfalfa on land badly infested with 
quack grass. 
In established fields, narrow-leaved plantain and dandelion are 
very abundant and persist indefinitely. Many alfalfa fields, even 
thickly seeded ones, are yellow with dandelion blossoms about May 
15 and a few days later white with the seed-heads which stand 
above the alfalfa. Wuld carrot and ox-eye daisy, so abundant and 
conspicuous in New York meadows, do not thrive in alfalfa fields 
except on bare spots, e. g., those caused by dodder. Such spots may 
be conspicuously white with ox-eye daisy blossoms at the time of 
the first cutting. Sweet clover maintains itself but two years. Dur- 
ing the latter part of May and forepart of June, in the second 
season after sowing, sweet clover plants growing among alfalfa may 
be readily distinguished by their taller and coarser growth. At the 
time of the June cutting the sweet clover plants stand 12 to 18 inches 
above the alfalfa. Being a biennial and unable to ripen seed, owing 
to the frequent mowing of the alfalfa, the sweet clover disappears 
entirely after the second season. Sweet clover hay is not relished 
by cattle. On rich soil, chickweed (Stellaria media) persists in al- 
