INSECT PESTS AND DISEASES 
On the Pacific Coast filberts are remarkably 
free from insect pests and disease. An aphis or 
plant louse sometimes appears on the foliage, but 
outside of dropping some honey dew in the leaves 
and branches, this insect does not seem to do much 
harm to the trees, and but little attention so far 
has been paid to it. 
The hazel bud mite has attacked certain sus- 
ceptible varieties, such as Prolific, Fertile de 
Coutard, Cosford, Princess Royal and others, and 
done considerable damage. Fortunately some of 
our most popular and valuable varieties, such as 
Barcelona and Du Chilly and others, probably by 
reason of difference in the construction of the buds, 
seem to be almost totally immune from the bud mite. 
The blight or fungus disease on the eastern 
American hazel (corylus Americana), which has 
attacked and killed the European filbert wherever 
set out in the eastern and southern states, has never 
been found on the Pacific Coast native hazel 
(corylus rostrata), nor on any of the European 
varieties cultivated in the Pacific Northwest. 
VARIETIES 
An important point in planting filberts is the 
selection and assembling of varieties. As none of 
the native American hazels have developed any 
varieties worthy of naming, propagating, or grow- 
ing in a commercial way, we must look to the 
foreign species for selections and cultivation. 
