MOSAIC OF SUGAR CANE AND OTHER GRASSES. 7 
sugar cane. Concerning the probable time of the importation that 
was responsible for the present wide distribution of mosaic in Amer- 
ica, the survey has brought out the fact, that the distribution of cut- 
tings by the Louisiana Sugar Experiment Station in 1914 and prior 
to that time has not resulted in establishing the disease at the points 
where such cane was received. Since 1914, however, every point 
receiving seed from the station has become the center of a larger or 
smaller infected area. The inference, of course, is that while the 
disease may have been present at the station for a few years prior 
to 1914, it had not become so widespread that every seed shipment 
from there contained some infected cuttings. At the present time, 
about 97 per cent of the cane plants at the station have the mosaic 
disease. It is probable that private individuals have imported cane 
with this disease, but such cane is not likely to be widely distributed, 
and its spread, therefore, must depend upon natural agencies, a 
much slower process. 
Without exception, every infested area in Georgia and Florida can 
be directly traced to distributions of seed cane from the Sirup Field 
Station at Cairo, Ga., since 1916, and the infection at this station 
dates from the importation of a number of varieties from Audubon 
Park in 1915. In nearly every instance where diseased cuttings 
have been received from Cairo, it has resulted in secondary infection 
of the surrounding native cane. 
The above is the brief and much condensed compendium of a large 
amount of data collected during July, August, and September, 
1919. It has made possible the recommendation of plans of attack 
upon the mosaic disease, which vary slightly in the different cane 
regions of the country, but all of which, if strictly adhered to by every 
cane planter, will bring the disease under control. Its capacity for 
rapid spread, as demonstrated in Georgia and Florida, means that 
a lapse of one year will result in immeasurably complicating the 
problem of ultimate eradication. 
LOSSES IN THE UNITED STATES. 
Since the mosaic disease had been unrecognized in this country until 
the writer announced its presence in July of this year, no extensive 
data have been accumulated to determine whether the losses caused 
by it in the United States are comparable with those sustained in Porto 
Rico. A few figures (Table II) have been obtained in Louisiana, 
however, which indicate that we may expect a decrease in yield 
almost equal to that in Porto Rico if the disease is permitted to 
become as widespread here as it is in that country. Losses here are 
held in check somewhat on account of frequent replanting. It has 
been noticed that where infected sugar cane is allowed to ratoon over 
a long period of years that losses due to the mosaic are more severe 
