8 BULLETIN 427, U. S. DEPARTMENT OF AGRICULTURE. 
but where potatoes are not habitually stored, the tuber moth is more 
in the nature of an annoying pest, causing minor losses practically 
every year, but becoming of primary importance only where condi- 
tions favor its increase. Careless planting, late and slow harvesting, 
and poor markets with the consequent holding back of the crop, would 
bring about such conditions. 
The tuber moth is reported to have done much injury to potatoes 
in Tasmania in 1855, and it was then stated that it "has of late years 
been making ravages amongst tubers in New Zealand" (1). 
In 1875 it was reported to have been injurious for the preceding 
years in Algeria. Specific instances give the losses at El-Bear as 
three-fourths of the entire crop (6). Meyrick (9) mentions large 
losses caused by it in Australia in 1878-79, and gives an authenticated 
case where four-fifths of the crop in one field was destroyed. The 
tuber moth was reported as destructive to potatoes in California in 
1881 and 1882 (13), and in 1901 (37). 
In 1897 the tuber moth was noted mining in tobacco in North 
Carolina (31) and in 1899 was mentioned as being destructive to 
tobacco and eggplant in Florida (33). In 1898 it was reported from 
South Africa as being common in potatoes, but, due to the fact that 
the potatoes were marketed very quickly, seldom causing much damage. 
Literature further records damage by the tuber moth in India in 
1906 (62). 
In Australia, India, Tasmania and New Zealand the damaging 
outbreaks have been of periodic occurrence from the time the tuber 
moth has been reported. Usually some explanation is given for 
this condition, and it is noticeable that the outbreaks generally occur 
during dry years. Authorities seem to agree that the tuber moth is 
a dangerous pest only to stored potatoes. 
This probably explains why the tuber moth attracts so little at- 
tention in the United States, where it has long been present. In the 
warm, dry sections potatoes are never habitually stored, and as 
these districts supply early potatoes for the neighboring States, 
under normal conditions the entire crop is harvested as early as pos- 
sible. 
Records of the Los Angeles County Horticultural Commission show 
that the importation of potatoes is twice as great in the fall as is the 
exportation in the early summer. This alone shows that normally 
potatoes once harvested are not held sufficiently long to permit in- 
festation by the moth, or once infested they are used up before their 
food value is materially impaired thereby. The tuber moth can 
become of importance only during times of poor market conditions, 
when the potatoes are held for a rise in price. 
