1899 
THE RURAL NEW-YORKER. 
75 
rtities of unused plant food. It has also been shown 
that superior tillage served to unlock enough food to 
furnish plants with the maximum of nourishment, 
yet with all these illustrations and facts before us, 
the nitrogen, phosphoric acid and potash remain in 
the soil unused, and where it is often becoming less 
available or suffering serious loss. Soil from which 
four successive large crops had been taken was found, 
on analysis, to contain in the fine earth 3 075 pounds 
w. PADDOCK. 
Geneva Experiment Station. Fig. 30. 
nitrogen, 3,784 pounds phosphoric acid and 12,063 
pounds potash per acre in the first foot of surface soil. 
For the purpose of comparison with the 16 soils first 
spoken of, these amounts must be reduced by one- 
third, since the one was computed on a basis of eight 
and the other on 12 inches depth. The 16 soils con¬ 
tained on an average, eight inches deep, per acre : 
Pounds. 
Nitrogen. 4,587 
Phosphoric acid. 4,267 
Potash.41,600 
The soil which had been cropped for four consecutive 
years without fertilizers or manures, eight inches 
deep, per acre: 
Pounds. 
Nitrogen. 2,050 
Phosphoric acid. 2,524 
Potash. 8,042 
Although this much-cropped soil contained but one- 
half as much nitrogen and phosphoric acid as did the 
16 soils analyzed, and only one-fifth as much potash, 
yet it produced without fertilizers or manures, this 
trying season, 22 tons of trimmed sugar beets per acre. 
The Available Food.— We must then conclude 
that it is not the amount of plant food which the soil 
contains, but the amount made available for the 
plants, which determines the yield. Our fathers sum¬ 
mer-fallowed the land to wake up the lazy plant food 
and make the soil productive. They realized the 
value of tickling the earth with plow shares, more 
fully than their children do. If we had studied the 
tillage problem more carefully, we would have dis¬ 
covered that three, or at least, two plowings could be 
given in one season, and then instead of leaving the 
land idle an entire season, keep it constantly employed 
by securing one or two crops and a cover crop to be 
left on the land to protect it from Winter degradation 
and to keep the plant food from becoming tired. 
The details by which better results are to be secured 
are many, but the principles to be observed are few, 
and the foundation of all progressive agriculture is 
improved tillage. But tillage produces best results 
where there is an abundance of vegetable material in 
the soil, and not only is this true, but humus of itself 
may be made to set free plant food as well as assist in 
conserving moisture and in cheapening tillage. 
The whole thought is not difficult to grasp. Plants 
require a suitable supply of moisture, humus helps 
the soil to hold on to moisture and materially assists 
tillage in liberating plant food, while the plow and 
other implements of tillage may be used to make 
available the elements of plant life in the particles of 
soil and to cooperate with the humus in breaking 
down inert material, and in forming a suitable seed¬ 
bed, while both assist in preparing a suitable reser¬ 
voir in the soil for the storage of moisture. 
DECAY AND PRESERVATION OF FRUITS. 
Discourses on the rotting of fruit and the ways and 
means of preventing it are always interesting to the 
horticulturist, especially if they help him at all in the 
fight which he must begin in his orchards in the 
Spring, and continue even through a part of the Sum¬ 
mer. Neither can he be entirely easy even after the 
fruit is harvested, so long as any of it remains in his 
storehouses. The changes which take place in the 
ripening of the fruit are, in sonje respects, similar to 
those in the rotting fruit. In the ripening, starch, 
abundant in the green fruit, is changed to cane sugar; 
the cane sugar is later changed in part to glucose. 
These changes may go on while the fruit is still on 
the tree, as in Summer fruits, or in the storehouse in 
late Fall and Winter. The change of the cane sugar 
into glucose does not improve the fruit, for glucose is 
less sweet than cane sugar. Fruit becomes sweeter as 
it ripens, because so much tasteless starch becomes 
sugar, and some of the sour acids are decomposed. 
When the fruit rots, if any cane sugar is left, 
it passes on into glucose, and the glucose itself is de¬ 
composed ; proteids and tannin are also decomposed ; 
new chemical compounds are produced that cause the 
brown color and disagreeable taste. Several species 
of fungi are the causes of the rotting of the fruit, and 
it is these that we must fight. Three important fungi 
that attack the fruit are Peneillium glaucum, Botrytis 
vulgaris and Oidium fructigenum ; this last one has 
long been known as occurring in every large collec¬ 
tion of fruit trees ; it attacks both ripening and ripe 
fruit, and is found even in the blossoms. Through 
the stem of the fruit, it can make its way into the 
twig and the leaves, killing both. The germs of the 
fungus are carried to the fruit by flies and wasps es¬ 
pecially. An apple was cut in two, and left on a 
table 18 feet from another table on which was a rot¬ 
ten apple much visited by flies ; in two days, the first 
apple began to rot. Flies may carry the germs in the 
hair about their legs and feet. In one season, when 
Oidium was very abundant on the fruit, wasps were, 
also, very numerous; in the two following seasons, 
there were very few wasps, and there was much less 
rotten fruit. 
The fungi appear to produce a poison which kills 
the cells of the leaves and fruit. A rotten apple was 
rubbed up with water. The clear liquid was divided 
into two parts, one of which was boiled and the other 
not. Boiling would kill all the germs of fungi and 
all kinds of ferments, but would not act on a poison. 
Several slices of the snowberry were treated with 
these two liquids, and both acted alike. The cells of 
the berry were killed by the boiled liquid as quickly 
as by the other, therefore, it must have contained a 
poison produced by the fungus. 
These fungi can live in a solution containing copper 
compounds, and it would seem that spraying with 
Bordeaux Mixture and other copper solutions would 
not kill them. But at several of the experiment sta¬ 
tions in this country, it has been proved that there is 
more sound fruit on sprayed trees than on those not 
sprayed. Such results have been obtained at the sta¬ 
tions in New York, Delaware, North Carolina, Ken¬ 
tucky, and in Canada. For the best results, the spray¬ 
ing must be continued even till the fruit begins to 
color. It was proved at one of the stations that fruit 
sprayed late contained only traces of copper or arsenic 
in the peelings and core of the apple, and none at all 
in the flesh of the fruit. Therefore, late spraying 
does not appear to be dangerous 
Cornell Exp. Station. [dr.J g. c. cAldwedl. 
THE APPLE CANKER. 
STORY OF A DANGEROUS DISEASE. 
The Disease Found.— At last year’s meeting of 
the Western New York Horticultural Society, the 
committee on botany and plant diseases reported the 
prevalence of Apple canker in the orchards in western 
New York, and a note on the subject from M. B. 
Waite, Washington, D. C., was read. Last Spring a 
request was received at the Geneva Experiment Sta¬ 
tion from Chapin Brothers, East Bloomfield, N. Y., 
that the dying of trees in their orchards be investi¬ 
gated. The visit revealed the fact that, of 80 acres of 
once fine orchard, belonging to one of the brothers, 30 
had been taken out, and one-half the remainder were 
not worth a shilling. Of the 45 acres originally in 
the other orchard, only about 10 are left that are of 
any value. It is evident that this wholesale destruc¬ 
tion is largely due to the canker. The disease has 
been noticed for the past six or eight years, but it has 
increased rapidly in the past three or four years. 
Twenty-Ounce is most susceptible, Baldwin, Wagener, 
Greening and King next. Talman Sweet seems prac¬ 
tically free ; trees on lowland and on ground at all 
wet, suffer worst. Trees in outside rows are freer 
from canker than those in less exposed situations. 
The orchard is 40 years old, but the trees that are free 
from disease are thrifty and in their prime. The or¬ 
chard has been cultivated far more intelligently than 
the average orchard. No crops have been taken, trees 
have been pruned regularly, and the orchard was 
thinned 15 years ago. It has been sprayed from the 
first with insecticides, but not with fungicides. 
What It Is. —Inquiries concerning the disease 
have been received from various sections of the State, 
and its prevalence is reported in widely separated 
localities.* It seems to be common in most parts of 
the State, and in a number of instances, is doing 
serious damage. It is also prevalent in the southern 
States, on the Pacific coast, in Michigan and Indiana. 
The swollen appearance of the limbs, the rough, 
blackened bark, and in many instances bare wood, 
black and decaying, are characteristics of this dis¬ 
ease. The cankers are much more prevalent on ma¬ 
ture than on young trees, the latter being evidently 
exempt from the attack. Old age and neglect seem to 
favor the disease, though thrifty trees may be ruined 
by its attacks. 
Its Life History. —Investigations of the nature 
and life history of the disease were at once begun. A 
series of cultures were made from the diseased bark, 
and various forms of fungi were obtained. Two forms 
constantly appeared in the cultures, and led to their 
being separated and being grown in a pure state in 
test tubes. One form proved to be a toadstool that is 
very common on dead bark and wood in the orchard, 
and the other was unknown. Inoculations were made 
with both forms, and in a few days there was an area 
of discolored bark around the place of inoculation in 
each case where the unknown fungus had been in¬ 
serted. Further inoculations were followed by the 
same results. By the close of the season, several of 
the seedlings were nearly girdled with wounds three 
or four inches in length, while on the trees, a portion 
of the wood was laid bare and the dead areas of bark, 
characteristic of the disease, were produced. Further 
experiments seemed to prove that the Apple canker 
is caused by the same fungus that produces the black 
rot of the apple, pear and quince. Some blighted 
apple twigs were examined, and it was afterward 
found that mature spores of the black-rot fungus were 
abundant on them. Some pear trees, also, which were 
found to be in a dying condition, were attacked by 
the same fungus. The spread of the disease was from 
the top downward. Fruit of the same fungus has, 
also, been found on twigs of some quince trees that 
grew by the side of the pear trees, although the in- 
j ary was slight. The canker has also been found on 
a quince tree in the Experiment Station orchards, the 
appearance and effect being much the same as on the 
apple trees. The disease was also found to be abund¬ 
ant and doing serious damage in the large orchard of 
Maxwell Brothers, near Geneva. A series of experi¬ 
ments was undertaken to prove that this fungus occur¬ 
ring on these different species of trees is the same and 
identical with the common black rot of the fruit. 
What Cau Be Done ?—Strong evidence seems to 
be produced that a well-known fruit disease will also 
attack and do serious damage to the trees themselves. 
Black rot of the fruit of apple, pear and quince can 
be held in check with Bordeaux Mixture, and there is 
no reason to think that this standard fungicide will 
fail in this case. Orchards that have been well sprayed 
with Bordeaux Mixture for several years past, are 
much freer from the disease than those not sprayed 
with fungicides. The disease seems to prefer mature 
trees, and it lives best in the rough bark, till it gains 
an entrance to the cambium. By removing or pre¬ 
venting the formation of this bark by spraying the 
limbs with Bordeaux Mixture, one favorite breeding 
place of this and possibly other plant diseases is re- 
prof. s. a. beach. 
Geneva Experiment Station. Fig. 31. 
moved. By keeping the limbs protected with Bor¬ 
deaux Mixture, all spores that chance to fall on them 
will be destroyed. Canker spots once formed cannot 
be cured, but such limbs should be removed wherever 
practicable. The rational way to combat Apple 
canker is to spray the limbs with Bordeaux Mixture 
as a preventive. This may be done when the trees 
are sprayed for Apple scab, and an earlier spraying 
when the growth first starts, would do no harm. 
Geneva Experiment Station. w. paddock. 
