1064 
Iht RURAL. NEW-YORK.FR 
Juno 12, 1920 
more. Tlie length of time will depend a good deal 
upon the rainfall, as heavy rains will wash most of 
the salt out of the soil. 
The railroads of this country have made many 
experiments in controlling weed growth along their 
right of way. and most of them are usually either one 
of the commercial weed killers or a solution of ar¬ 
senate of soda. This is very poisonous to animals, 
and we should hardly care to recommend it for gen¬ 
eral use. unless it can he used with the utmost intel¬ 
ligence. Certain oils will also destroy vegetation, 
mineral oils being about the only ones that are cheap 
enough for popular use. Certain waste chemicals 
from industrial works are often used, but either heavy 
application of common salt or some form of arsenic 
will be found most useful. 
Arsenite of soda is a powerful plant poison and it 
is reasonably cheap and readily obtained. In han¬ 
dling it the greatest care must be taken not to inhale 
the dust or vapor, and not to swallow any of the ma¬ 
terial by putting the lingers to the mouth. The best 
plan is to wear leather gloves having long wrists. 
Of course, poisons of this sort should never be left 
where children or animals can reach them. The 
utensils used in preparing them should not be used 
for other purposes, and should be thoroughly washed 
after each handling. The arsenite of soda has a 
brackish or salty taste which is agreeable to ani¬ 
mals, and they will frequently eat it or lick it up if 
they can gain access to it. Where it is used the 
animals should have plenty of salt to satisfy their 
appetite, and in making it the hands should be pro¬ 
tected by thick gloves, and care taken to keep the 
dust or the liquid away from the body. The arsen¬ 
ite of soda is a compound formed of white arsenic 
and soda. It is rather difficult to obtain ready¬ 
made, and most of those who use it in large quan¬ 
tities make it themselves. Most persons who have 
had experience in handling chemicals can make this 
poison without great trouble. 
The Department of Agriculture gives two definite 
methods of making the material. The first is given 
as follows: 
Formula I.—Caustic soda (sodium hydroxide), 2 lbs., 
or high-grade concentrated lye, 3 lbs.; white arsenic (ar¬ 
senic trioxide), 4 lbs.; water, to make 1 gal. 
Mix the caustic soda or lye with the white arsenic 
in a wooden, earthenware or graniteware receptacle. 
Add the water slowlv. In about 30 seconds the solution 
will begin to boil violently, when it should be stirred 
vigorously with a wooden paddle. The heat generated 
by the chemical reaction is usually sufficient to cause all 
the arsenic to dissolve and the mixture to become a gray, 
syrupy liquid. In case some of the arsenic remains in 
suspension, however, it will be necessary to heat the so¬ 
lution until the arsenic disappears. After the solution 
is cool, add enough water to replace that lost by evapo¬ 
ration. 
The caustic soda is the granulated form, and of 
the grade known as 95 per cent technical. The white 
arsenic is a fine powder, and in the technical grade 
is usually 9S per cent pure. This compound will re¬ 
main in the liquid condition for a week. If wanted 
longer it must be stored in an air-tight container. 
Another formula suggested by the Department 
runs as follows: 
Washing soda (sodium carbonate or sal-soda), S lbs.; 
soda or soda ash (anhydrous sodium carbonate). 4 lbs.; 
white arsenic (arsenic trioxide), 4 lbs.; water to make 
1 gal- , , 
Neither washing soda nor soda ash are poisonous, and 
they are somewhat cheaper than caustic soda or lye. 
The mixture, however, does not generate heat upon add¬ 
ing water, and must be boiled to bring the arsenic into 
solution. The caustic soda preparation is a slightly 
stronger weed killer. 
Either method can be employed, and one gallon of 
the prepared solution contains about 4 lbs. of soluble 
arsenic, or 51/3 lbs. of arsenite of soda. To use 
them, dissolve one gallon of either of the above mix¬ 
tures in 50 gallons of water, or smaller quantities in 
the same proportion. Under average conditions, 
with mixed grasses and weeds not over 6 ft. high, 
and with the soil reasonably moist. 000 gallons of this 
solution are required for one acre. Thus, one gallon 
of the mixture, properly diluted, will cover an area 
60x00 ft. The best results are obtained on a cloudy 
Section of Holler. Fig. 310 
and humid day. about 12 hours before rain. Ilot, dry 
weather is not so satisfactory, and the treatment 
should not be given where the soil is very wet. 
When growth of vegetation is large it should be 
mowed off and the poison applied after several days. 
This poison does not kill all plants with equal effect. 
In some cases it is necessary to make several appli¬ 
cations, especially in such cases as quack grass or 
dock, while new growth comes readily up from the 
roots. The poison can be applied from a sprinkling 
can, a small watering cart, or a garden hose and 
nozzle. Those who experiment with this matter 
must remember that they are handling a strong and 
dangerous liquid and should take no chances what¬ 
ever with any careless treatment. 
Cedar Rust on York Imperial Apples 
What is the truth regarding cedar rust on York apple 
trees? A lot of people claim that the rust does not 
originate on the red cedar tree, but that it comes from 
diseased apple trees. Our county passed a law that 
cedar trees should be cut. and it is causing a great deal 
of trouble, as some people object to cutting the cedar 
tree. e. ii. a. 
Virginia. 
N INTERESTING EXPERIMENT—We have 
been studying this disease for some time and T 
have devoted quite a hit of attention to it since 1912. 
1 would suggest the following experiment, which may 
Bearing for Axle. Fig. 311 
be a trifle complex, but will give every satisfactory 
proof if properly carried out. York Imperial apple 
twigs may be covered with ordinary paper sacks, 
about No. 20 size, as soon as the leaves have begun 
to open out well, or at about blooming time. Several 
twigs should be covered in this way. Each twig 
should be marked with a large.tag fastened firmly to 
it, so that there will be no question as to which one 
you are working with in case you should remove the 
sack to examine the twigs at. any time. These sacks 
should be allowed to remain on the twigs undisturbed 
for at least 10 days or two weeks, so that new 
growth will come out in case there may have been 
rust infection on the older leaves which were opened 
when the sacks were first put out. The sacks on 
some of the twigs may then be removed during a 
warm rain and some swollen rust galls from the 
cedar may be brushed lightly across the young leaves, 
which have been protected by the sacks. Some twigs 
must he left covered to serve as checks on those 
which you are inoculating with the rust. The rust 
galls must also be thoroughly moistened and gela¬ 
tinous. The leaves should he moistened artificially, 
unless the rain at that time is sufficient to moisten 
them by leaving the sacks off for a few minutes. The 
twigs so treated should now lie covered again with 
the sacks, and they should he allowed to remain in 
place for at least two weeks longer. They may then 
he uncovered, and you will find some evidence of 
yellowing on the young leaves where the rust galls 
were used. You will find no evidence of this kind 
mi the young leaves of the twigs which have been 
sacked for the entire period. You will find that the 
rust spots which do show will increase in size and 
may cause premature dropping of the leaves. 
PERIOD OF INFECTION.—We have found that 
year after year the rust galls on the red cedar will 
produce the rust which is common and prevalent on 
York Imperial apples. We have not found any other 
form of rust or any other form of disease on apple 
or other trees which would produce the rust on York 
Imperial. We have found that the fungus causing 
this disease lives for approximately 21 months on the 
red cedar and approximately three months on the 
apple. In other words, the infection of the cedars 
from the apples shows up very slowly and the galls 
do not reach full development until more than a year 
and a half after the cedars have become infected. 
This is. however, a rather minor incident, and was 
first determined by Dr. Heald of Nebraska. We have 
found that the apple leaves become immune in a 
comparatively few days. Some of the first leaves to 
come out may become immune in 10 to 12 days; some 
of the later leaves may require 25 to 28 days before 
they become immune. We have found that the 
weather is undoubtedly the most important factor 
to he considered, both as regards infection of apple 
foliage and the maturity of the foliage which results 
in its immunity. We have never known of a serious 
infection taking place when the temperature was 
below 55 degrees Fahrenheit, and from laboratory 
experiments it would seem that an infection below 
this temperature could not take place in nature. In 
1917 the cedar trees were literally loaded with galls, 
so that many of them drooped from the weight, yet 
the amount of rust infection on York Imperial was 
relatively slight because of the low temperature 
prevailing whenever moisture conditions were favor¬ 
able for infection. 
IMMUNITY AND RESISTANCE—Apple leaves 
become immune at about the time they cease grow¬ 
ing. Under West Virginia conditions we do not 
expect a rust infection of any serious proportion 
after the first week in June, and our most serious 
infections have always occurred by or previous to 
the middle of May. We have devoted a considerable 
portion of time to control measures and are firmly 
convinced that it is unwise for commercial orcliard- 
ists in the Shenandoah Valley to attempt any spray 
program for the control of the disease. The destruc¬ 
tion of red cedar trees has greatly reduced the 
amount of rust in orchards in Berkeley County, West 
Virginia. We have excellent evidence along this 
line, as we have been collecting specimens year after 
year showing the amount of rust in various orchards. 
We have a large variety of orchards planted in Hardy 
County. West Virginia, where we are testing 80 
commercial varieties selected by the horticulturist 
in order to determine their resistance to rust and 
other diseases as well as their value for commercial 
planting. This orchard is planted in duplicate and 
contains eight trees of each variety. From the data 
which we secure within the next three or four years 
we may be able to advise commercial varieties which 
will be suitable in some sections of West Virginia 
where it seems impractical to eradicate the red 
cedar. In the meantime we are making good progress 
toward the eradication of the red cedars in the prin¬ 
cipal apple growing regions in the eastern panhandle. 
The result has been a great improvement in the 5 ork 
Imperial fruit and in the general health of the trees. 
West Virginia Experiment Station, n. j. glddings. 
