ON FRUITS
Bright colours of fruits--Unripe fruits and their
effects--An intemperate Fungus--Oranges--Prickly pear and
the monkey--Strong seeds--Bill-of-fare of certain birds--A
wood-pigeon and beans--Ants and seeds--Bats, rats, bears,
and baboons--The rise in weight of a Big Gooseberry--Mr.
Gideon and the Wealthy Apple--Crossing fruits--Breadfruit and
banana--Dates--Figs--Olives--Pineapples by the acre--Apples and
pears--Home and Canadian orchards.
AT Christmas time and during late autumn, there is but little colour
in the country. Most green grasses have become a dull greyish-green,
and the leafless brown and grey branches of the trees are not, at
first sight, particularly interesting.
But amongst this monotony of sober colouring, points of bright red
or flaming scarlet may be noticed here and there. Sometimes it is
a spray of Hips (the fruit of the Rose), or it may be a cluster of
Hawthorn berries. At Christmas the Holly is positively gaudy with its
bright scarlet fruit set off by the shining dark green leaves.
Most fruits are some shade of red, but every fruit is conspicuous and
easily seen.
[Illustration: _Queensland Government Photo_
PINEAPPLES AS A FIELD CROP
This is one of the important harvests in some parts of
Queensland.]
There is the most extraordinary range in colour. The Snowberry and
Dwarf Cornel are pure white. The Mistletoe is a yellowish green.
Pure yellow fruits are not common, but some of the Cucumber orders
and Lemons are lemon or orange-yellow. The bluish-black of the
Blaeberry or Bilberry, of the Bramble, and of many Plums and Prunes,
goes along with a rather peculiar shade of green in the leaves which
sets them off. The black Elder berries, on the other hand, have
bright red or pink stalks which contrast prettily with them. The
colours of apples vary: many of them have been rendered a gorgeous,
glossy red through cultivation. One of the most beautiful colour
contrasts in Nature is found in the rich black of the Olive, with its
background of shining white twigs and silver-green leaves. Another
very curious harmony is that of the Spindle tree fruit, which has
a hard dull red case that opens to display the seeds: these are
enclosed in a bright orange fleshy cup.
Changes often occur. The Lily of the Valley fruit is at first green,
then becomes flecked with red, and finally is a rich scarlet. Juniper
berries change from green to purple.
Now there is always some meaning in Nature for any series of facts
such as these. Why are these fruits so brightly coloured and so
conspicuous?
Birds and other animals are intended to scatter the fruits and
seeds, and so the fruits must be easily distinguished at a distance.
The seeds are taken to some other place, where they germinate and
form a new plant. This furnishes the clue and guide to many other
peculiarities in fruits and seeds.
The pleasant smell of ripe apples, plums, strawberries, and other
fruits, also attracts birds and other animals. But the sugary juice
and delicious flesh is developed entirely for the purpose of making
it worth a bird's while to eat it. The amount of sugary matter is
enormous, and the seeds seem very small and inconspicuous compared
with this luscious mass. The sugar is produced very rapidly towards
the end of the ripening period.
A Cucurbita fruit, for instance, may increase in weight at the rate
of·0032 ounce per minute. All who have gathered strawberries know how
quickly they ripen.
The way in which the sugar is formed is not understood, but unripe
fruits contain bitter, unwholesome acids and essences which may
produce colic or very unpleasant effects if the fruits are eaten
green. Thus the colour is a guide to the animal, who is not supposed
to eat the fruit until it is ripe; if eaten green, the seeds inside
the fruit are quite destroyed and cannot germinate. Yet animals are
so greedy that young birds, young animals of all sorts (even girls
and boys) will and do eat green or half-ripe fruit. In this present
year there is no doubt that many children have suffered for having
done this. Yet if we come to think of it, throughout all the millions
of years during which fruits have ripened, Nature has every year
clearly told young pterodactyls and other lizards, young birds, young
monkeys, and young people to wait till the fruit is ripe. None of
them have learnt to do so.
When investigating by experiment, on the vile body, the properties of
plums, strawberries, and other fruits, you are sure to find here and
there one that has decayed and become rotten. In most cases this is
because a bird has pecked a hole in it, or because the outside skin
has been broken by a wasp. The sugar has then begun to ferment. Why
does it do so?
If you gather a few fruits, put them into a jar of sugar-water, and
leave it after closing the mouth with a bunch of cotton wool, then
in a day or two fermentation begins and alcohol is produced. That
is because, on the outside of the fruit, there were hundreds of an
objectionable little fungus. It lives upon sugar and turns the latter
into alcohol. This yeast fungus is really a living distillery. It
lives in the midst of alcohol all its life, dying eventually (like
the Duke of Clarence in his butt of Malmsey wine) by alcoholic
poisoning, which it has brought about by its own work. This little
yeast fungus can only be seen with a microscope. From a rotten fruit
it drops on to the ground, where it remains all winter. Next spring
certain small insects (green-fly and the like) carry some of these
yeasts from the earth to next year's fruits. But the skin of the plum
or apple, or the hairs on a gooseberry, or the delicate, waxy bloom
on a grape, will prevent these insects or wasps from laying open the
sugar inside the fruit to the attacks of yeasts and other fermenting
fungi.
Some fruits appear to have "favourites"; they seem to prefer that
large animals should eat them. If you look carefully at a piece of
orange peel, and cut a small piece across, you will see distinctly
small resin pits full of a curious essence which gives the
characteristic taste to marmalade. This bitter stuff will prevent
wasps from touching the sugar. It is, however, a valuable material,
and some kinds of lemons, etc., are grown chiefly for this oil,
which is obtained by scraping the peel with a little saucer which is
studded with short pins.
A still more extraordinary fruit is the prickly pear; this is very
delicious though very difficult to eat. Indeed, only monkeys and man
seem able to enjoy it. The sugary part and the seeds form a little
round mass in the inside. The outside part, though also fleshy,
contains hundreds of minute mineral needles, which stick in the
tongue and lips and cause most painful inflammation. The monkey eats
the prickly pear with very great caution, getting his fingers into
the top and scooping out the sugary part. Man requires a teaspoon to
do this satisfactorily.
Another very curious point about these fleshy fruits (and also
ordinary ones) is the strength of the seed inside. It does not look
very strong.
But an orange seed, for instance, will not be in the least injured
if you put it between two glass plates and gradually press upon the
upper one up to even a pressure of some thirty pounds. Even hemp
seed, which seems quite weak, will endure a weight of four pounds. It
is impossible to break a prune stone, or to injure a date stone, by
standing with your whole weight upon it.
Such strength is necessary because many of these seeds are eaten
by birds and ground up in their crops with bits of china, stones,
shells, and the like, which the birds pick up just to help them in
crushing their food.
Fruits and seeds would seem to be exposed to some danger when they
are lying on the ground. Horses or other heavy animals might tread on
them. But the strength of seeds and their shape is such that no harm
is likely to accrue. For instance, I arranged a thin layer of garden
earth (a quarter of an inch thick) on a glass plate; upon the earth I
placed four hemp seeds; then I put a 58-lb. weight on the top of the
seeds. They were not in the least injured, although the seed of the
hemp is not a particularly tough one. Under such conditions the seed
simply slips into the earth.
This is made easy for it on account of its shape, which is generally
rounded above and below. A transverse section of a seed would be in
shape like the arch of a bridge and its shadow in the water, at least
in many cases. There are also usually wonderfully thickened cells in
the shell or coat of a seed, which makes it tough and strong.
The following are a few cases of strong seeds or fruits:--Cotton seed
bears a weight of 19 to 20 lb.; the hard fruits of the Dogrose,
33 lb.; Castor-oil seed, 17 lb.; Hornbeam nuts, 27 lb.; Pine seed
(various sorts), from 11 to 22 lb.; Yew seeds, 16 lb.; Peas, 50 to 56
lb. In every case they are not at all hurt by these pressures.
As regards the animals for whom fruit or seeds are of great
importance, birds are of course the commonest. The following is part
of the bill-of-fare of a few of our common birds:--Thrushes eat
blaeberries (bilberries), brambles and mulberries. Missel-thrush (or
mavis) is especially fond of the mistletoe.
Now the berry of the mistletoe is exceedingly sticky and glutinous,
and in the course of the bird's meal these sticky strings get on to
the bill and feathers, so that the mavis wipes its bill on the branch
of a tree. When it does so the seed becomes attached to the branch,
and is drawn close to the latter when the viscous matter dries up,
and so takes root on the branch.
Nightingales and robins eat strawberries and elderberries; blackbirds
are very fond of strawberries, gooseberries, and raspberries.
Wood-pigeons eat beechmast, acorns, and, according to Pliny,
mistletoe-berries also, but this latter author has not been confirmed
by later observers. Some of the wild African pigeons are exceedingly
fond of castor-oil seeds. When travelling through the Central African
bush, it is often necessary to shoot your dinner (if you are to have
any at all), and castor-oil bushes can be relied upon to produce
pigeons, if you are content with and are able to shoot them.
There is a widely-spread belief in the country that a great quantity
of berries means that a very severe winter is going to follow. But
as a matter of fact the winter of 1904 was not a severe one, and yet
there were enormous quantities of berries.
We are still ignorant of many details about birds and berries. It is
not quite clear how the seeds are not destroyed, though experiments
have shown that they are not injured, by passing through the body
of a bird. Kerner von Marilaun, for instance, tried the fruits and
seeds of 250 different plants which were offered to seventeen birds,
as well as to marmots, horses, cattle, and pigs. He found that from
seventy-five to eighty-eight per cent. of the seeds germinated
afterwards so far as regards the blackbird, song-thrush, rock-thrush,
and robin. Quail also bring seeds from Greece and the Ionian Islands
to Sicily.
Mr. Clement Reid says: "Some years ago I found ... in an old
chalk-pit the remains of a wood-pigeon which had met with some
accident. Its crop was full of broad-beans, all of which were growing
well, though under ordinary circumstances they would have been
digested and destroyed."[110] Such accidents are common.
[110] Reid, _Origin of the British Flora_.
But it is not only birds which eat fleshy fruits and seeds. Even the
tiny, industrious ant drags about seeds of certain plants. Sometimes
they gather up corn or grasses, such as ant-rice, and store them
for use in winter. They even bite off the growing root to prevent
the seeds germinating and spoiling. Occasionally they seem to carry
the seeds by accident, as, for example, those of the cow-wheat and
a few others which resemble their cocoons in size, colour, and
form. In other cases there is a little fleshy excrescence on the
seed which they are fond of eating. Cyclamen, snowdrop, violet, and
periwinkle seeds are supposed to be carried in this way. Many animals
occasionally or regularly eat fruits. There are, for instance,
the flying-foxes or fruit-eating bats of Madagascar and tropical
countries, which may be seen hanging from the upper branches of
trees by their toes, with their heads tucked away under their wings.
When disturbed a little fox-like head appears, and after much
chattering, scolding, and expostulation, the creature unhooks itself
and flies away with a strong flight not unlike that of a crow. Horses
are occasionally fed on peaches in Chile. Rats eat the coffee cherry,
and do a great deal of harm in coffee plantations.
In Cashmir the mulberry and other fruit trees are sometimes visited
by sportsmen, who often find bears feeding on the fruits. Pigs, of
course, eat all sorts of fruit, and several other mammals do the
same, but it is especially monkeys that live chiefly on fruit. They
plunder the banana plantations, and in South Africa melon-patches
require to be most carefully watched to prevent baboons from
destroying them.
It is said that the baboons watch the plantations from a distance,
and will only come down if they think no one is there: so five people
walk to the patch, and while four go away again, one of them remains
in hiding to shoot the baboons, who cannot tell the difference
between four and five.
Man himself is, and has always been, a great eater of fruit. Not only
so, but he has enormously improved and altered wild fruits until
they are modified into monsters of the most extraordinary kind. The
ordinary wild gooseberry weighs about 5 dwt. But even in the year
1786 some of the cultivated forms weighed double this amount (10
dwt.), and in 1852 gooseberries which weighed more than 37 dwt. were
in existence. What size the largest big gooseberry may be this year
is not very easy to say, because the public Press is at slack times
too energetic about the question. The most usual way of improving
fruits is by selecting the finest specimens for reproduction. It is
by this means that the original wild banana, which is a rather small
fruit with very large seeds and very little flesh, has been altered
into something like 150 varieties, of which the immense majority
have no seed at all. This is a very extraordinary fact, because the
seed is the reason for the existence of the fruit. Of course, all
such varieties must be reproduced by suckers (like the banana) or by
grafts, or in some such non-sexual manner. Seedless varieties exist
of the Cucumber, Fig, German Medlar, Diospyros, and Orange.
In the case of seedless varieties of the Vine, it has been found that
it is necessary to carry pollen to the flowers to fertilize them, and
the seedless fruit is also very much smaller in this case, not more
than a quarter of the size of one that has seeds.
The following instance is typical of the manner in which many
well-known kinds of fruit have been developed, though the
perseverance shown by Mr. Gideon is certainly not common. About the
year 1855 this gentleman began planting apple trees of about thirty
named varieties. For nine years he continued his experiments. He not
only planted trees, but also sowed apple seed sufficient to produce
a thousand trees every year. Yet the cold winters were so severe
that at the end of ten years one small seedling crab apple was the
solitary survivor. One seedling of this turned out to be hardy enough
for the climate of Minnesota, and this, the "wealthy" apple, has been
of great importance to the Northern Mississippi growers. It is to be
hoped that the name has been justified in Mr. Gideon's case.
[Illustration: _Stereo Copyright, Underwood & Underwood_
_London & New York_
BANANA CARRIERS IN JAMAICA
A West Indian negro thinks nothing of walking twenty miles with
loads such as these.]
Many other cases could be mentioned of a chance variety produced as a
wild plant, and then propagated non-sexually for long periods, e.g.
the New Rochelle Bramble, which was found by the roadside, and
which turned out to be exceedingly valuable. It is by crossing or
hybridizing that the most extraordinary results have been obtained.
Sometimes with plums, the hybrids of the first generation are nearly
double the size of their parents. Some of the crosses are between
different plants. The Loganberry, for instance, is said to be a cross
between a Raspberry and a Bramble. It ripens in July, and is said to
be far in advance of either of its parents as regards juiciness and
acidity.
In most cases, however, the crosses are between well-established
varieties or races of the same species, and both hybridizing and
selection are employed to get the desired result.
There are several tropical fruits which, with the possible exception
of wheat and oats, are more important to mankind than anything else.
The Breadfruit (_Artocarpus incisus_), which is very common in the
South Sea Islands, has a large fruit the size of a melon. When baked
in an oven heated by hot stones, it forms a satisfying meal: it is
rather like new bread, but has very little flavour. Coarse cloth is
made of its bark, and the wood is used as timber. The tree also has
a milky juice containing indiarubber, and is employed for caulking
the canoes. The most interesting point for botanists about this plant
is that the fruit is made up of thousands of little flowers, and the
fleshy part is really the stalk. Fossil trees of this genus (of the
chalk period) are found in some parts of Europe.
Still more important to mankind is the Banana (_Musa paradisiaca_).
It is wheat, corn, and potatoes all in one, in tropical and
sub-tropical countries. It is found all over the world wherever there
is a hot, moist climate and shelter from wind. It is a most generous
plant as regards the amount which it will produce. It will yield
about 19-1/2 tons of dry fruit on a single acre, which is about
forty-four times the amount given by potatoes and 133 times that of
wheat. Moreover, it differs from almost every other fruit in being
both "rice and prunes," that is, it is nutritious and wholesome, and
yet at the same time succulent. There are still people who declare
that the taste is that of "cotton wool and Windsor soap," but that
is a frivolous and unjust remark. It is very difficult to prepare
it exactly in the right way for export to Great Britain, and the
slightest change in temperature or period of gathering has the most
distressing results.
As with many other tropical fruits, the countries where it is most
carefully produced and where the trade is most important are just on
the borders of the tropics. There Europeans can keep enough vigour
and vitality to supervise and watch over the labour of natives. It
is in the Canary Islands, Queensland,[111] and Jamaica that the
cultivation is most carefully looked after. The yield may be from
five hundred to a thousand bunches per acre, and the value of the
trade is enormous. A plantation is not very beautiful, because
the huge leaves break up into irregular, ragged pieces which look
untidy. The flowers are visited by the beautiful little honey-sucking
sunbirds and humming-birds. Monkeys also are very fond of the fruit.
[111] Queensland in 1900 had 6215 acres, and produced 2,321,108
bunches of bananas.
In the tropics it grows everywhere, and with extremely little
trouble. It is a doubtful blessing to the negroes, for they get their
food so easily that they tend to become incorrigibly lazy. Jam,
champagne, brandy, and meal can be made from the banana. When this
meal can be prepared satisfactorily, it may partly replace wheat in
temperate countries. Besides this, the leaves are used for thatching,
and the stalks which make the stem contain a valuable fibre which is
used for string and rope.
In Egypt and all along the great deserts of Sahara and Asia the
graceful stately Date palm gives the favourite food of the people
(see Chap. X.).
The Arabs grind up the stones to make food for camels, and sometimes
ferment the sap to make toddy. The trees are either male or female.
The Arabs knew that it was necessary to pollinate the female flowers
with male pollen long before the meaning of the process was realized
in Europe.
The Fig, a native of the Persian Gulf, is cultivated all along
the Mediterranean and in India, Australia, and California. It is
sometimes fifteen to thirty feet high, and reaches a very great
age. There is one at Finisterre said to be several centuries old.
It yields fruit worth about £14 an acre. The most interesting point
about the Fig is the way in which the Fig-wasp carries the pollen
(see Chap. V.).
Olives are also one of the most important and characteristic
Mediterranean trees. The crop in both Spain and Italy is worth
about £8,000,000 to £9,000,000 annually. In California it is also
successfully cultivated, and pays very well. The peculiar taste of
the dessert olive is obtained by soaking it in lime or potash, and
then in vinegar or salt.
The Pineapple is one of the most delicious fruits, and is interesting
in every way. The little sharp spines on the edges of the leaves
keep animals off, and also make it a little difficult to harvest.
The workmen must wear leather trousers to prevent their being cut
and torn by the leaves. In Queensland the pineapple is grown in big
fields, and about ten thousand fruits (worth about one penny each)
can be got from a single acre. It is also grown in the West Indies,
in India, and in other tropical countries. If you examine the horny
outside skin of the fruit with a sharp penknife, you will find that
each little piece of the mosaic is a flower in itself; with a little
care the bracts, three sepals, three petals, and six stamens can be
distinguished. The whole stem and all its flowers unite to make a
compound fruit. Most varieties have no seeds. It is a native of South
America.
It is, however, our home fruits, Apples, Pears, Gooseberries,
Strawberries, Raspberries, and Currants, that are most important
to us in Britain. The Wild Crab Apple is found from Drontheim, in
Norway, to the Caucasus, and grows over the whole of Europe. Apples
were known to the Greeks and Romans.
Unfortunately, in our own climate there are great dangers in the
orchard. A touch of frost when the flowers are ripe will very likely
kill the tender, green, baby apple. It is perhaps in Canada and
North America that the growing of apples and pears is most carefully
looked after. Our beautiful old orchards in Devonshire and other
places, with comfortable grass below the trees, and moss-covered,
picturesque, ancient trunks, are not found in the New World. The
regular lines of young trees in bare, carefully-kept earth, with
every stem whitewashed and treated with the most scientific monotony,
produce a most valuable return. But in this country those who are
careful and scientific sometimes obtain extraordinary results. It
is on record that a man with a holding of twenty-nine acres near
Birmingham made £600 a year from this small plot and paid £250 for
labour on it.[112]
[112] _Journal Royal Horticultural Society_, vol. 27, part iv.
Mr. Gladstone also said that the future of British farmers depended
upon jam. Yet it must be remembered that the trees take a long time
to come into bearing, and the crop is most uncertain.