B. P. 1.—729. 
THE NEMATODE GALLWORM ON POTATOES AND 
OTHER CROP PLANTS IN NEVADA.’ 
INTRODUCTION. 
During the seasons of 1910 and 1911 there occurred in certain irri- 
gated potato-growing districts of Nevada an outbreak of a potato 
disease known locally as the eelworm. Particular attention was 
attracted to the ravages of this disease because several carloads of 
potatoes shipped from Nevada into California during the winter of 
1910-11 ‘were condemned by certain county horticultural commis- 
sioners of California and were returned to Nevada to be disposed of 
elsewhere. A recurrence of the disease in the season of 1911 and the 
shipment of infected potatoes into California resulted in the issuance 
by the State Commissioner of Horticulture of California of an order 
establishing a quarantine against all potatoes shipped into that State 
from the counties of Lyon, Churchill, and Washoe, in the State of 
Nevada.? 
Since California markets have afforded the chief outlet for the 
potatoes grown in Nevada in excess of local needs and since pota- 
toes have been a very profitable crop in certain irrigated districts 
in Nevada, the closing of California markets to their potatoes has 
been severely felt by Nevada potato growers. The outbreak of 
the so-called eelworm disease or nematode gallworm disease in 
these Nevada potato fields has been so severe and the results so 
disastrous as to warrant bringing together the available information 
concerning this disease as it affects potatoes and other crop plants, 
for the assistance of the affected districts in Nevada. Some of this 
information may be applicable also to other sections of the country, 
1 Owing to a severe outbreak of a potato disease in certain irrigated districts in Nevada, caused by the 
nematode Heterodera radicicola, there has been an urgent demand for information as to the cause of the 
disease, the probable extent of its spread, and the possible remedies. Inorder to meet thisdemand for infor- 
mation a committee was appointed, consisting of Dr. N. A. Cobb, Technologist, Prof. L.C. Corbett, Horti- 
eulturist, Dr. W. A. Orton, Pathologist, and Mr. C.S. Scofield, Agriculturist, all of the Bureau of Plant 
Industry, to bring together such available information as would be most useful to the potato growers and 
others concerned. While the present interest in this nematode is due to its attacks on potatoes, it should. 
be clearly understood (1) that the same nematode is parasitic on many other important crop plants, where 
it may cause damage, and (2) that this is but one of a number of species of parasitic nematodes. It is 
important to keep these facts in mind to avoid serious mistakes in dealing with the present problem in 
Nevada and similar problems that may occur elsewhere.—B. T. GALLOWAY, Chief of Bureau. 
2 For further details in reference to this quarantine order, see Monthly Bulletin of the State Commissioner 
of Horticulture of California, vol. 1, December, 1911, pp. 26-30; and also the same publication for January, 
1912, in which a modification of this order was published. 9 
29196°—Cir. 91——12 B) 
