New York AGRICULTURAL EXPERIMENT STATION. 211 
dodder seeds may retain their viability when buried in the soil is not 
known, but it is believed to be several years. Hence, if the dodder 
is known to have produced seed the land should be planted witn 
other crops for one or two years, at least, before it is reseeded with 
zifalfa. On the other hand, if the dodder did not seed it is entirety 
safe to reseed with alfalfa at once. Asa rule, dodder does not seed 
in New York so that the risk in reseeding infested fields is probably 
not great. 
The writers have tested this in five different fields of one-fourth 
acre each. One of these fields, located at Fayetteville, was two 
years old when plowed up because of dodder. It was then planted 
with tomatoes for two seasons. In the spring of 1906 it was re- 
seeded with alfalfa seed known to be free from dodder. No trace 
of dodder was found in the new seeding which was kept under ob- 
servation for two years. Another field, near Geneva, ruined by 
dodder in 1905 during the first season after sowing, was plowed up 
in the spring of 1906 and reseeded in May with dodder-free seed. 
No dodder appeared up to the close of 1908. A one-year old dod- 
der-infested field at Oakfield was plowed up in the spring of 1906 
and at once reseeded. No dodder appeared during the time the 
field was under observation, viz., one year. A fourth field, located 
near Canandaigua, was ruined by dodder during the first season. 
In the spring of 1907 it was plowed up and reseeded and has re- 
mained free from dodder up to date (October, 1908). The fifth 
field was located at Caywood. It was first seeded in the spring of 
1905. Dodder became very abundant the same season, but the field 
was allowed to stand until about June 20, 1906, when it was plowed 
up and planted to beans. The following spring it was reseeded 
with alfalfa. The writers did not see this field during the autumn 
of 1907, but the owner informs us that no dodder appeared in it. 
An interesting feature of this field is the appearance of one colony 
of dodder among the beans. Perhaps this came from seed, but 
there is another way in which it may have originated. Many alfalfa 
plants survived the plowing in 1906. They came up thickly among 
the beans. It is quite possible that some of these plants harbored 
the dodder until after the beans were large enough to receive it. 
YELLOW TREFOIL. 
Owing to the occasional adulteration of alfalfa seed with the seed 
of yellow trefoil (see page 188) this plant has recently come inta 
considerable prominence in New York. The name yellow trefoil 
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