FLORIDA STATE HORTICULTURAL SOCIETY 
95 
fumigation of slips before planting ver¬ 
sus non-fumigation. 
The above mentioned experiments were 
started nearly two years ago on the A. N. 
Hoofnagle place, one and one-half miles 
south of Ft. Pierce. The plants are now 
bearing their first crop. Three things 
loom up very conspicuously in these ex¬ 
periments, namely: 
1. Cuban slips by far are giving the 
best results. 
2. Of the local slips those chosen for 
their vigor and from healthy plants are 
far outranking those that showed weak¬ 
ness at the time of planting or those taken 
from wilted plants. 
3. The plots whose slips were fumi¬ 
gated with hydrocyanic acid gas, at the 
rate of 2 ounces of sodium cyanide to 100 
cu. ft., are superior to those not so 
treated. Just why fumigation should 
make such a difference in the growth of 
the plants has not yet been explained. 
With regard to the soil sterilization 
plots it is yet too early to draw any defi¬ 
nite conclusion. During all of the first 
year the plots, including the checks, looked 
uniformly well, all plots growing as vig¬ 
orously as in the days when the pineapple 
was in its prime on the East Coast. Even 
during this year, until just recently, the 
plots appeared to be quite uniform and 
bore a good crop of large-sized apples. 
But about six weeks ago the plants of the 
outside row on one side of one of the 
check plots began to show some wilt. 
Just the other day it was observed that 
the wilting has crept in as far as the 
fourth row. So far no wilting appears in 
any plant of the other check plots nor in 
any of the sterilized plots. As said be¬ 
fore, it is still too early to draw any def¬ 
inite conclusions with regard to the ster¬ 
ilization plots, but in another year some 
very interesting points may be cleared up. 
Although these sterilization plots do 
not at this time give us anything definite 
with regard to soil sterilization, yet they 
bring out another interesting and most 
important feature in the soil improve¬ 
ment problem. These plots are located in 
a part of the experimental field that had 
Natal grass growing on it since 1916. 
The grass had been left undisturbed, hav¬ 
ing been neither cut down nor plowed in 
until just before the slips were planted 
when the ground was plowed. Each bed, 
whether treated or not, produced uni¬ 
formly large and vigorous plants. This 
vigorous growth cannot be attributed 
alone to the sterilization of the soil, for 
the reason that the check plots, until only 
recently, produced equally vigorous 
plants. This uniformly fine growth of 
pines was undoubtedly due, first, to the 
humus that was restored to the soil by the 
three years’ continuous growth of Natal 
grass; and second, to the partial starving 
out of the nematode, as the Natal grass 
is highly resistant to this dreaded enemy 
of the pineapple. 
This humus theory is further substan¬ 
tiated as follows : Plants growing in an¬ 
other part of the same field, but where the 
grass was plowed under two or three 
times a year, are not doing nearly so well 
as those where the grass had not been dis¬ 
turbed. Likewise on still other parts of 
the field where more recent plantings 
have been made under these particular 
cultural differences, the plants show less 
vigor in the plots that had the grass 
