FLORIDA STATE HORTICULTURAL SOCIETY 
27 
wave struck us, and strange to say, all of 
those that were banked before the freeze 
are just as bad as those that were not 
banked. Why that was, I don’t know. 
It may have been because the earth had 
not had time to settle around them. 
Mr. Hart: Did you open the bank up 
after the freeze? 
Mr. Stevens: No. They were bank¬ 
ed a day or two before the freeze and 
the dirt had not settled around them. 
Mr. Hart: I think it is advisable to 
open up and let them warm up. 
Mr. Sheppard: One of the troubles 
we have on these frosted trees on the 
young leaves, is the mellanose fungus. 
I have already seen it coming and about 
in May I think it wise to apply ammonia- 
ted fertilizer. In '95 there was a visita¬ 
tion of the mellanose. This was greatly 
benefited in its after effects by about a 
five per cent of ammonia in the fertilizer. 
It decreased after then and was not seen 
in the fruit. 
Mr. Hume: One of the things we will 
naturally look for following the freeze 
is a greater development of die-back than 
we have seen in the state for some time. 
We have been hearing less of it, but un¬ 
less I miss my prophesy very badly, we 
will have more of it within the next few 
months. 
CONTROL OF ROOT KNOT BY CALCIUM CYANAMIDE 
J. R. Watson 
PREFACE 
In November, 1914, the attention of 
the writer was called to the poisonous 
properties of the commercial compound 
called “cyanamid.” It occurred to him 
that the substance might have some value 
against pests inhabiting the soil, and ne¬ 
matodes at once came to mind. Some 
preliminary tests, tried out on radishes 
in infested soil, were so encouraging that 
during the spring of 1915 more extensive 
tests were undertaken, and in July of that 
year the matter was taken up as a regular 
project for investigation. We have had 
variable results as we varied the dosage, 
the manner of application, and the soil. 
We will not here go into the details of 
these experiments, but will give only the 
essential results and such details as are 
essential to the trucker and gardener in 
applying the material. 
“cyanamid ” 
“Cyanamid” is a trade name for a mix¬ 
ture consisting chiefly of the chemical 
compound calcium cyanide (about 45%), 
hydrated lime (27%), carbon (13%), 
calcium carbonate (4%), calcium sul¬ 
phide (2%). It is a black powder, the 
color being due to the carbon. It is a 
concentrated nitrogenous fertilizer which 
analyzes from 15 to 24 per cent, of am¬ 
monia. At present prices it is the cheap¬ 
est source of ammonia available among 
commercial fertilizers. It contains no 
potash or acid phosphate, and is there¬ 
fore, not a complete fertilizer. 
