100 
FLORIDA STATE HORTICULTURAL SOCIETY. 
found to be of some benefit, using one 
part of commercial formalin to ioo parts 
of water; but it is necessary to apply sev¬ 
eral gallons of this solution to the square 
yard, and it is impossible to get the 
ground thoroughly and evenly soaked so 
that its use is entirely out of the question. 
Carbonbisulphide, about a teaspoonful 
poured into a hole six inches deep, at 
intervals of about 15 to 20 inches, the 
holes being immediately covered with soil, 
is very efficacious, but is entirely impac- 
ticable except for very small areas, on 
account of the expense which would 
would amount to $60 to $100 per acre 
for the. chemical alone, not including the 
cost of applying it. I do wish, how¬ 
ever, to report success with certain rota¬ 
tion experiments that were conducted at 
my suggestion in Denison, Texas. A 
gentleman was very much troubled by 
rootknot in his muskmelons, it becoming 
so abundant that he lost his whole crop 
in 1904. At my suggestion he planted 
his field that fall with winter grain. The 
following spring, 1905, he sowed Iron 
cow peas on the land, this variety, if pure 
seed is obtained, being absolutely immune 
to rootknot. In this connection, however, 
I must emphasize the fact that it is 
necessary to have pure seed, for I have 
observed, and so have others, rootknot 
in seed alleged to be Iron, though in the 
pure bred Iron cowpea I have never seen 
it. The owner of the land carefully de¬ 
stroyed all weeds that came up among 
the cowpeas until the latter covered the 
land so thoroughly that all weeds were 
smothered out. In the fall the land was 
again sown to grain and in the following 
summer Iron cowpeas were planted the 
second time; in the fall of 1906 the land 
was again put in grain and in the spring 
of 1907 was planted partly to melons and 
partly to other crops. All proved to be 
absolutely free from rootknot. Another 
piece of land in which he had Iron cow¬ 
peas but one year was found to have very 
many less nemadotes than before, but was 
not yet entirely free from the trouble. 
Regarding the methods of introduction 
and spread of this nematode, my observa¬ 
tions lead me to believe that to a large 
extent nursery stock has been responsible 
for the introduction. Once introduced in¬ 
to a man’s farm, the disease is easily 
spread by his tools or the dirt clinging 
to his feet or the feet of his animals, and 
even by washing rains. If the proper pre¬ 
cautions were taken on new land that 
had never been cultivated before to use 
only clean tools and to see that the horses, 
wagons and plows did not bring dirt with 
them, the disease would not prove serious. 
When once introduced, however, it does 
not take very long, if susceptible crops 
are grown, for it to become thoroughly 
established and injurious, for from the 
time that the egg is laid until the mature 
worm is laying eggs herself is only about 
four weeks, and one worm is able to' lay 
from 400 to 500 eggs. 
