NEw YorK AGRICULTURAL EXPERIMENT STATION. 193 
from and a mistake may have been made. Anyway, the crop was 
practically ruined by dodder during the first season. 
These examples show the importance of using proper samples for 
analysis; also, that absolute confidence should not be placed in an 
analysis. As an additional precaution against dodder the writers 
advise the sifting of alfalfa seed as described under the next 
heading. 
SIFTING SEEDS TO REMOVE DODDER. 
Trouble with dodder in alfalfa fields is usually due to the use 
of dodder-infested alfalfa seed. Since much of the alfalfa seed 
on the market in New York is more or less infested with dodder 
it is often difficult to obtain dodder-free seed. The statements of 
seed dealers should not be relied upon. Most of the alfalfa seed in 
this State is handled by hardware merchants and small seed dealers 
who, themselves, do not know dodder seed. As dodder seeds are 
much smaller than those of alfalfa they may be easily overlooked. 
Good-looking seed, otherwise clean, may be badly infested with 
dodder. Even so small an amount as one dodder seed per pound 
makes alfalfa seed dangerous to sow until properly cleaned. 
Farmers are advised to protect themselves against dodder by sow- 
ing no alfalfa seed until it has been pronounced dodder-free by a 
seed expert or else sifted as directed below. The safest method is 
to have the seed both analyzed and sifted. 
The idea that alfalfa seed may be freed from dodder is not a 
new one. But prior to the appearance (in January, 1907) of Cir- 
cular No. 8 of this Station®’ the information on the subject avail- 
able to New York farmers was too meager and indefinite to be of 
any practical value. It is not sufficient to state merely (as has some- 
times been done)**® that a 20-mesh sieve should be used. It is 
necessary to know, also, the size of the wire, where sieves of the 
proper kind can be obtained and how they are to be used. To the 
uninitiated it may seem that the size of the wire is unimportant, 
but, in practice, it makes all the difference between success and 
failure. With a given mesh, the larger the wire the smaller will 
be the openings. It is desirable that the openings shall be as large 
as possible without permitting the passage of an unduly large 
amount of alfalfa. After several experiments on sifting dodder- 
infested seed with sieves of various kinds the writers reached the 
** Stewart and French (08). 
* Hillman (43, p. 8; 45, p. 10); Selby and Hicks (93). More explicit 
directions are given by Hillman (46, p. 20). 
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