642 
Journal of Agricultural Research 
Vol. XXTII, No. g 
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(3) Burning did not decrease the total number of grass plants, as is 
generally thought to be the case. The data show that at the end of 
four years there were 21 per cent more squares containing grass plants 
on the burned area than there were when the experiment started. On 
the other hand, the increase in the unbumed plot was only 7 per cent. 
These data, while not final, indicate that the evil effects of binning, if 
any, are not always apparent in the first four years. 
(4) There was a decrease during the 
four years in the number of sedges 
on the burned area, while on the un¬ 
burned plot a tendency to increase was 
observed. 
(5) Burning caused a change in the 
composition of the grass type on 
the experimental area. Big bluestem 
(Andropogon furcalus) decreased on the 
burned plot, while on the unburned 
plot it showed a decided increase. On 
the other hand, burning increased the 
number of plants of little bluestem 
{Andropogon scoparius) ) although the 
number decreased on the unbumed 
plot. Kentucky bluegrass increased 
much more rapidly on the unbumed 
area. Bluegrass starts very early in 
the spring, and it appears that it may 
have been more easily injured than 
other grasses which start late. Many 
plants were green when the burning 
was done. Side oats grama decreased 
on both burned and unbumed plots. 
(6) In 1918, when the experiments 
were started, both areas were prac¬ 
tically free of weeds. In 1919 a great 
many were found on both burned and 
unbumed plots. From this date on 
there was a decrease each year in the 
number of weeds on the burned plot, 
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Fig. 
Graph showing weekly mean maxi¬ 
mum and minimum temperatures in 1920 at 
a depth of 1 inch under the surface on burned 
and unbumed plots. 
while on the unbumed one their number increased. 
(7) Mean maximum soil temperatures at a depth of i inch averaged 
12.1 0 F. higher on the burned plot. The mean minimum temperatures 
were also higher by 4.1 ° on the burned plot. Similarly, at a depth of 3 
inches mean maximum and minimum temperatures were 3.6° and 4.2 0 
higher, respectively, on the burned plot. These dataTnay explain why 
growth starts earlier£ when the old vegetation has-been removed by 
burning. 
(8) The vegetation from each plot was cut about September 10 each 
year. The average yield was slightly greater on the- unburned area. 
The difference, however, was slight, except during one season,*^and in 
another season it was in favor of the burned plot. 
(9) The conclusion is that studies so far conducted have failed to show 
that burning is injurious. More extensive experiments with different types 
of vegetation and for a longer period of time must be conducted before 
final conclusions regarding the effects of burning can be arrived at. 
