THE TOWN-WOODS OF CARLSBAD (BOHEMIA). 139 
last forty years has been mostly planted with a mixture of oak, 
maple, sycamore, and beech. Many of the young woods date 
from about 1868 to 1875, when considerable damage was done 
here by storms, snow-break, and injurious insects throughout 
the older crops. 
The woods in this second and more distant zone are treated 
somewhat more sylviculturally than those in the first zone, so as 
to form larger and more homogeneous, but yet ever-varying and 
always typical, groups of woodland scenery, instead of aiming 
mainly at the production of fine and picturesque individual trees 
and small groups of trees. But here, too, pleasing effects and 
zesthetic considerations are the first and chief object of manage- 
ment, while the amount of net income desirable is entirely a 
minor consideration ; and the compartments into which this area 
is subdivided vary from about 50 to 110 acres each, which is 
considerably larger than the compartments in the first zone. 
The portion of the working-plan now in force for this second 
zone is based on a rotation of too years, which of course, 
however, permits of fine old trees being retained long in excess 
of that age adopted as the general average. The distribution of 
the age-classes was found in 1900 to be approximately as 
follows :— 
ACREAGE OF AGE-CLASSES. | 
Acres and Years. | 
race eS Ad 3 | pelotal 
I-20 | 21-40 | 41-60 | 61-80 | 81-100 a 
Normal Distribution, 495 | 495 495 495 | 495 | 2475 
Actual Distribution, 480 650 300 445 | 600 | 2475 
| a1 Ve 
Variation from the) +] -:: i) 155 ony | 105 +260 
Normal, . 5 =| aa aS 195 Om Ul) Bare — 260 
This age-class table is reconstructed every ro years, after stock 
has been taken of the growing crops, and its main use is to 
enable a clear view to be taken as to the progress of their 
regeneration. But meanwhile the annual fall made each year is 
based on the average annual increment on all the existing crops, 
and this is at present estimated at about 50 cubic feet actual 
contents (or nearly 40 cubic feet by square-of-quarter-girth 
measurement) per acre. Inclusive of thinnings, the mean 
