THE NATIONAL NURSERYMAN 
i iS 
TRIALS OF VARIOUS GASES FOR FUMIGATING 
NURSERY STOCK TO KILL SAN JOSE SCALE. 
W. E. Britton. 
Entomologist Agricultural Experiment Station, New Haven, Conn. 
In the spring of 1907 we undertook some tests of various gases to 
ascertain if any of them could be used to better advantage than 
hydrocyanic acid gas for fumigating nursery stock. Hydrocyanic 
acid gas is a dangerous poison, and many nurserymen and fruit 
growers have the idea that it injures the stock. At the outset we 
aimed to use only such gases as could be generated readily and 
cheaply on a large scale and without expert chemical knowledge. 
The following gases were selected: Carbon disulphide and 
carbon tetrachloride, which are volatile liquids; chlorine, sul¬ 
phuretted hydrogen, acetylene and hydrocyanic acid gas, which are 
generated by chemical action. About six hundred peach and apple 
nursery trees of salable size but infested with San Jose scale, were 
obtained. Ten trees were used in each test in most cases (five trees 
in some instances), and The trees were afterward carefully planted in 
nursery rows, where they could be watched during the season. 
Though commenced in 1907, the tests were continued in the 
spring of 1908, and the present paper is merely a brief summary of 
the results. For the details of the tests the reader is referred to the 
biennial Report of the Connecticut Agricultural Experiment Station 
for 1907—1908, pages 270 and 796. 
The chief difficulty encountered in the use of volatile liquids is 
the variability of conditions in volatilization. Temperature is a t 
great factor, as is the size and shape of the vessel holding the liquid. 
Both carbon disulphide and carbon tetrachloride will volatilize 
much more readily at high than at low temperatures, and from a 
broad, shallow vessel than form a deep, narrow one. 
In order to make these conditions as uniform as possible, we 
resorted to the use of heated “spiders” or stew pans made of cast 
iron, which retain the heat for several minutes. The pans were 
heated tb 200 °Fahr., then placed in the tight box with the trees and 
the liquid poured through a funnel into the pan and the hole stopped 
by means of a cork. By this method the liquid was transformed 
into gas almost immediately, so that the effect of the whole quantity 
throughout the entire fumigation period was gained. This would 
not be the case where the liquid volatilized slowly. Quantities of 
carbon disulphide varying from 10 to 80 fluid ounces per 100 cubic 
feet were tried. The period of fumigation also varied from one to 
six hours. The results indicate that the minimum quantity of this 
liquid necessary to kill the scale is 20 ounces per 100 cubic feet act¬ 
ing for one hour. The maximum is 30 ounces acting for two hours. 
Intermediate quantities and fumigating periods gave satisfactory 
results. Larger quantities caused injury to the trees. 
Carbon tetrachloride destroyed the scale in our 1907 experi¬ 
ments, but as contradictory results were obtained a year later, we 
cannot at present recommend this liquid. 
Of the gases generated by chemical action we may discard 
at once: Chlorine, on account of the inconvenience of generating it 
and its injurious effect on the trees; acetylene, because in the 
quantities used it failed to destroy the scales; sulphuretted hydro¬ 
gen, which killed the scales and some of the trees, because the 
present methods of generating it are too cumbersome and incon¬ 
venient to be used by nurserymen. 
Hydrocyanic acid gas, when used at the rate of one ounce of 
cyanide for each 100 cubic feet (as is practiced by nurserymen) 
destroyed all of the scales and caused no injury to trees/even with a 
fumigating period of two hours, which is nearly four times as long as 
the usual period. Trees dripping wet were fumigated for one hour 
without injury. Three times the above quantity for one-half hour, 
or double the amount for two hours, caused no injury. These 
results correspond with those obtained by other experimenters in 
several different parts of the country. 
It will be seen from these tests, therefore, that for fumigating 
nursery stock nothing has been tried which appears to be superior to 
hydrocyanic acid gas, though it is possible that some other fumigat¬ 
ing agent may later be found. Carbon disulphide may, however, be 
used for fumigating cions, bud-sticks and small lots of trees or 
plants, if the directions herein given are followed. As this liquid is 
inflammable and explosive, caution should be used in handling it, 
especially to keep fire away from the fumigating house or box. 
It is unquestionably true that many trees have been injured by 
improper fumigation in the past few. years. The trees may have 
been immature, too wet, or may have been left for too long a period 
in the fumigating house. There is also the chance of making mis¬ 
takes in computing the quantities of chemicals or in weighing them. , 
But even against these dangers there is a greater possibility that the 
trees have been injured by becoming too dry or by freezing, and the 
orchardist has laid it to fumigation. 
In conclusion, I wish to state that in these tests more apple than 
peach trees were injured by the various gases. Peach is com¬ 
monly regarded by nurserymen and orchardists as being especially 
susceptible to injury from fumigation. 
TRADE WITH DEPENDENCIES OF THE UNITED 
STATES. 
It is a striking indication of the commercial importance of the 
newer dependencies of the United States to learn that $50,000,000 
worth of merchandise was shipped from different parts of the 
United States to these non-contiguous possessions during the fiscal 
year 1906. The fact that nearly $68,000,000 worth was shipped by 
them in return is still more striking. Of the amount shipped out 
$18,000,000 or 36% were made up of farm products, and of the 
amount received by the United States, 81% or $55,000,000, were 
farm products. Among the heaviest shippers in the group of de¬ 
pendencies is Hawaii. Porto Rico is one of the largest receivers, on 
the other hand. Alaska receives large quantities of timber and 
packing house products. Hawaii receives flour, barley, and feed 
stuffs. The amount of farm produce sent to the Philippines is com¬ 
paratively small, considering their relative importance. Sugar is 
one of the heavy items coming to the U. S. from Hawaii. Manila 
fibre and sugar also come to us in large quantities from the Philip¬ 
pines. 
FARM TRAIN SPECIALS. 
Horticulture and Soil Improvement: The idea of equipping 
and despatching special trains for the giving of instruction in some 
particular field of agriculture has been rapidly extending in recent 
years. Corn specials have been run in Iowa, Kansas and Nebraska, 
and other states. Maine has run a potato special instructing the 
farmers how to grow the Irish tuber, and Indiana has through the 
co-operation of the Baltimore and Ohio run a special for the purpose 
of instructing farmers how to improve their soil conditions, and 
better their fruit growing practices. In New York the Erie and 
New York Central Railways have cooperated with the college of 
agriculture in this work and trains have been run in the western and 
northern parts of the state for the purpose of stimulating dairying, 
farm crops production and fruit growing. 
A CYLINDRICAL FRUIT PACKAGE. 
A new type of package, so far as the external form is concerned is 
that manufactured by W. R. Stokely, St. Augustine, Florida. The 
crate is in the shape of a drum, and has adjustable corrugated parti¬ 
tions. There are six of these removable sections, which avoid the 
necessity of wrapping oranges to prevent bruising. The crate is 
provided with ventilation. The cost is said to be about the same 
as the orange box now in use, and is reported to be adaptable to 
carrying oranges as well as deciduous fruits, tomatoes, and straw¬ 
berries. The inventor has organized a factory and the new crate is- 
being placed upon the market quite rapidly. 
M. J. Wragg, of Illinois, says: “I appreciate your journal and 
like to have it come to my desk.” 
An advertiser should put his soul into his advertisements and 
then try to save it. - Agricultural Advertising. 
