(Figures 6 and 7) 
Hectare Coordinates of the Chesapeake Bay Center for Field Biology 
These maps represent a grid system which provides a large number 
of fixed points for designating sampling stations and recording 
collections. Each square of the grid is 100 meters on a side and 
has an area of 10,000 square meters or 1 hectare (1 hectare = 2.471 
acres). The squares may be easily broken down into smaller metric 
units. Each of the larger squares (with heavier borders) contains 
100 hectare squares. 
The vertical grid lines run north and south at right angles to 
the baseline, not according to magnetic north. The heavy horizontal 
line crossing Java Farm is the baseline; trees and brush along this 
line have been cleared to make a relatively open footpath. 
Disturbance to the vegetation along the other grid lines has been 
kept to a minimum. 
Although the grid lines on these maps extend beyond the boundaries 
of the Chesapeake Bay Center, the actual surveying has been confined 
to the Smithsonian property. In the field the corners of each 
Square are pinpointed either by concrete monuments or by pipes 
driven into the ground. The monuments are placed two hectares apart, 
and have brass plates bearing the numbers of the adjoining squares. 
Where pipes are used, stakes bearing the grid numbers accompany 
them. No markers have been planted in the estuaries. 
