Statistical Notes. 185 
Owing to these high prices the gross yield of some 
Swiss forests is the largest known in Europe, the city 
forest of Zurich exhibiting yields of $12.00 and the city 
forest of Aarau as much as $14 per acre on the average, 
although in the Alps forests the gross yield sinks to $3 
and $4. The more intensively managed city forests 
mentioned spend on their management $6 and even $7 
per acre, while most of the State forests keep their 
expenditures within $2.50 to $3.50, and in some places 
down to $1.50 per acre. The net yields vary therefore 
for the State and communal forests of the plateau coun- 
try between $3 and $6.50 for some of the city forests 
from $6.50 to $8 and $9. 
Switzerland has long ago ceased to produce its wood 
requirements and imports from 6 to 8 million dollars 
annually of wood and wood manufactures. 
