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CHAPTER XIX
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.

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."¹¹² Such accidents are common.

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.

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,¹¹³ 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.

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.¹¹⁴

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.