TRANSECTS 179 
‘as for the line transect, except that the record covers a decimeter strip just 
‘as in quadrat work. Accordingly, an interval of a centimeter is left on the 
sheet between the successive portions of the strip, in order that the latter 
may be put together without confusion when the topographic map and the 
plant series are combined. The record should invariably start in the upper 
left-hand corner and read down. The map and the centimeter strip record- 
ing the plants of the transect are combined on a common scale as already 
indicated for the line transect. 
The ecotones of zones are shown on belt transects by single cross lines, 
and those of consocies by parallel cross lines. In taking photographs of the 
transect, it is desirable to use guidons to mark these points clearly. The 
same device may also be used to indicate the course of the transect, when the 
tapes are completely hidden by the plants. Physical factor readings should 
always be taken, and, as before, they are best made at the intersections of the 
ecotones. 
The Permanent Transect 
221. Advantages. Both line and belt transects, after they have been re- 
corded, should be rendered permanent, in order that they may serve to indi- 
cate the changes of a heterogeneous area from year to year in the same 
detailed fashion that the permanent quadrat does for homogeneous ones. 
For ‘historical as well as for physical reasons, the ecotones of zones and of 
consocies are subject to change from year to vear, and the amount and di- 
rection of this change can cnly be ascertained from annual records made in 
exactly the same spot. By means of the permanent transect alone the very 
origin of such areas can be followed from one stage to another of the suc- 
cession. Moreover, the transect is-equally valuable with the quadrat in 
making it possible to follow every step of the minute changes wrought by 
competition. 
222. Details. The transect is made permanent by blazing the landmarks 
at either end, if these already exist, or by erecting them when it is necessary. 
A label stake is driven at each end, on which is painted the number and date 
of the transect and its length. Each stake should also indicate the exact di- 
rection in which the other lies. The position of the ecotone is indicated by 
smaller stakes bearing the number of the transect and the date when the 
ecotone was found at that point. These are left in place, and in a few years 
show very graphically the change in position of the zones. For the first 
season, permanent transects afford results of great value when recorded for 
each aspect, but after this an annual visit will suffice. The details of map- 
ping, plotting, etc., are identical with those indicated above, with the addition 
