"The grading, seeding, facing, and packing have become separate branches of the industry, and the work is nearly all done by especially trained women, who have become experts at it. The establishments in which this work is done furnish employment for over 5000 persons. The aggregate pay roll each month during the season is between $200,000 and $350,000."

GRAPE-VINEGAR

A very good vinegar can be made from grapes, although as yet this outlet for over-production is not largely utilized in America. Grapes which are unsuitable for raisins, dessert, wine-making or grape-juice can be used for vinegar-making. Under the most favorable conditions, grape-vinegar cannot compete in cheapness with vinegar made from numerous other products and must, therefore, always sell at a high price. Indeed, it is doubtful whether a high-grade grape-vinegar can be manufactured at a less price than good wine. The production of grape-vinegar requires as much care, but possibly not as much expert knowledge, as the making of wine. Unlike the latter, however, the vinegar can be produced on a small scale for domestic purposes by any one possessing a knowledge of wine-making or vinegar-making.

Grape-vinegar may be manufactured from either white or red grapes, although that from white grapes is generally preferred. It may be made either directly from grapes or from wine, the acetifying process being the same for both. There are, therefore, two distinct stages in the manufacture of this product. First, there must be alcoholic fermentation by which the sugar in the grape is changed into alcohol with the escape of carbonic acid gas. Second, acetic fermentation must follow the alcoholic fermentation by which the alcohol is changed into acetic acid.

BY-PRODUCTS OF GRAPE INDUSTRIES

There are several valuable by-products in the wine-making and grape-juice industries, and even raisin-making yields a by-product in the seeds taken from the raisins. The utilization of these wastes has been rendered profitable in Europe, and there is no reason why by-products should not yield considerable profit in America, as a few already do. Good authorities state that if all the wastes of the grape crop could be utilized the value of the crop would be increased over 10 per cent.

_Pomace._

The pomace or marc, the residue left after grape pressing, is the most valuable of the by-products of the wine and grape-juice manufacturers.

If the pomace is permitted to ferment, and afterwards is distilled, a product called pomace-brandy is made. Unscrupulous wine-makers often add water and sugar to pomace, after which it is refermented and the resulting product is sold as wine. Notwithstanding the fact that the word "wine" as applied to this product is a misnomer, the total amount of such wine made and consumed in America is large. Piquette is another product in which the pomace is put into fermenting vats, sprinkled with water and the liquid after a time is drawn off, carrying with it the wine contained in the pomace. This liquid is re-used in other pomace, until it is high enough in alcoholic strength, when it is distilled into "piquette" or "wash."

In Europe, the pomace from stemmed grapes is said to make a sheep and cattle food of more or less value when salted slightly and stored in silos. The pomace is also oftentimes used as a manure, for which it has considerable to recommend it, being rich in potash and nitrogen.

Acetic acid is made from pomace by drying it in vapor-tight rooms, during which process 50 to 60 per cent of the weight of the pomace becomes vapor, and this, condensed, yields considerable quant.i.ties of acetic acid.

_Cream-of-tartar._

The lees of wine, the sediment which settles in the casks in which new wine or grape-juice is stored, form a grayish or reddish crust on the inside of the receptacle. This is the argol or wine-stone of the wine-maker, and from it is made cream-of-tartar, an article considerably used in medicine, the arts and for culinary purposes.

From 20 to 70 per cent of the lees consist of either cream-of-tartar, or of calcium tartrate, the latter also having commercial value. Red wines are much richer in argol than white wines. A ton of grapes yields from one to two pounds of argol. This product becomes a source of considerable profit in large wineries and in grape-juice manufacturing plants.

_Seeds._

In Europe, the seeds are separated from the pomace and used in various ways. They are also utilized to a smaller extent in America, especially when separated from raisins. The seeds are used as food for horses, cattle and poultry, for which they are said to have considerable value. If crushed and ground, the seeds yield a clear yellow oil which burns without smoke or smell and which may also be employed as a subst.i.tute for olive oil. A ton of grapes yields from forty to one hundred pounds of seeds from which may be made from three to sixteen pounds of oil. This oil is also used as a subst.i.tute for linseed oil and in soap-making. Besides oil, the seeds yield tannin.

After the oil and tannin have been taken from the seeds, there remains a meal which may still be utilized as a stock food or as a fertilizer.

DOMESTIC USES FOR GRAPES

At present, when food conservation is being emphasized everywhere, mention of the domestic use for grapes is particularly appropriate.

The country over, no fruit is more generally grown than the grape; yet grape products are not as common for home use as those of several other fruits, although many attractive and appetizing preserves can be made from grapes without the use of large quant.i.ties of sugar, spices or other ingredients. Few housekeepers realize the high quality and the cheapness of the products that can be made from the grape. Thus, grape-juice, jelly, jam, marmalade, grape-b.u.t.ter, catsup, spiced grapes, canned grapes, conserves in which grapes are used, preserves and mince-meat are among the desirable culinary products easily and cheaply prepared from home-grown grapes or those bought in the market.

Only simple domestic utensils are needed in the preparation of any of these products.

Grape-sirup is less easily produced, yet can be made in any home without the addition of sugar. It is not only a good table sirup, but is a most useful sugar subst.i.tute for the preparation of other culinary products. The Muscadine grapes in the South, to be purchased by almost every householder in southeastern United States, in particular, are useful for these domestic products. Recipes for all of these products can be found in cook books, and one or two bulletins and circulars from the United States Department of Agriculture give recipes for preparing grapes for domestic purposes. Farmers' Bulletin 859 ent.i.tled _Home Uses for Muscadine Grapes_ is a particularly valuable publication on this subject.

It is interesting to note that several large manufacturers of grape-juice are putting on the market grape jams, jellies and marmalades. It would seem that these delicious and wholesome products would find a ready sale in the markets of the country, and that their manufacture would prove profitable to the maker and to the grape-grower. The greater the use of grapes for their products, the better the grower can breast the blows of unfavorable markets and over-production.

[Ill.u.s.tration: PLATE XX.--Isabella (2/3).]

CHAPTER XV

GRAPE-BREEDING

Chance, pure and simple, has been the greatest factor in the production of varieties of American grapes. From the millions of wild plants, an occasional grape of pre-eminent merit has caught the eye of the cultivator and has been brought into the vineyard to be the progenitor of a new variety. Or in the vineyards, more often in near-by waste lands, from the prodigious number of seedlings that spring up, pure or cross-bred, a plant of merit becomes the foundation of a new variety. An interesting fact in the domestication of the four chief species of American grapes is that none came under cultivation until forms of them, striking in value, had been found. Catawba, representing the Labrusca grapes; the Scuppernong, the Rotundifolias; Norton, from _Vitis aestivalis_; Delaware and Herbemont from the Bourquiniana grapes; and Clinton from _Vitis vulpina_, are, after a century, scarcely excelled, although in each species there are now many new varieties.

That our best grapes have come from chance is not because of a lack of human effort to produce superior varieties. Of all fruits, the grape has received most attention in America from the generation of plant-breeders just pa.s.sing. Grape-breeders have produced 2000 or more varieties, a medley of the heterogeneous characters of a dozen species. That so many of this vast number are worthless is due more to a lack of knowledge of plant-breeding than to a lack of effort, for the order and system in plant-breeding that now prevail, disclosed by recent brilliant discoveries, were unknown to grape-breeders of the last century.

GRAPE HYBRIDS

As early as 1822, Nuttall, a noted botanist, then at Harvard, recommended "hybrids betwixt the European vine and those of the United States which would better answer the variable climates of North America." In 1830, William Robert Prince, Fig. 48, fourth proprietor of the then famous Linnean Botanic Nursery at Flushing, Long Island, grew 10,000 seedling grapes "from admixture under every variety of circ.u.mstance." This was probably the first attempt on a large scale to improve the native grapes by hybridizing, although little seems to have come of it. Later, a Dr. Valk, also of Flushing, grew hybrids from which he obtained Ada, the first named hybrid, the introduction of which started hybridizers to work in all parts of the country where grapes were grown.

[Ill.u.s.tration: FIG. 48. William Robert Prince.]

Soon after Valk's hybrid was sent out, E. S. Rogers, Fig. 49, Salem, Ma.s.sachusetts, and J. H. Ricketts, Newburgh, New York, began to give viticulturists hybrids of the European Vinifera and the American species which were so promising that enthusiasm and speculation in grape-growing ran riot. Never before nor since has grape-growing received the attention in America as given during the introduction of Rogers' hybrids. It was the expectation of all that we were to grow in America, in these hybrids, grapes but little inferior, if at all, to those of Europe.

A statement of the difference between European and American grapes shows why American viticulturists have been so eager to grow either pure-breds from the foreign grape or hybrids with it.

[Ill.u.s.tration: FIG. 49. E. S. Rogers.]

European grapes have a higher sugar-and-solid content than the American species; they, therefore, make better wines and keep much longer after harvesting and can be made into raisins. Also, they have a greater variety of flavors, which are more delicate, yet richer, with a pleasanter aroma, seldom so acid, and are always lacking the disagreeable, rancid odor and taste, the "foxiness," of many American varieties. There is, however, an unpleasant astringency in some of the foreign grapes, and many varieties are without character of flavor.

American table-grapes, on the other hand, are more refreshing, the unfermented juice makes a pleasanter drink, and lacking sweetness and richness, they do not cloy the appet.i.te so quickly. The bunches and berries of the European grapes are larger, more attractive and are borne in greater quant.i.ties. The pulp, seeds and skins are somewhat objectionable in all of the native species and scarcely so at all in the Old World sorts. The berries of the native grapes sh.e.l.l from the stem so quickly that the bunches do not ship well. The vines of the Old World grapes are more compact in habit and require less pruning and training than do those of the native grapes; and, as a species, probably through long cultivation, they are adapted to more kinds of soil, to greater differences in environment and are more easily propagated than the American species.

Because of these points of superiority in the Old World grape, since Valk, Allen and Rogers showed the way, American grape-breeders have sought to unite by hybridization the good characters of the Old World grape with those of the American. Nearly half of the 2000 grapes cultivated in eastern America have more or less European blood in them. Yet, despite the efforts of the breeders, few of these hybrids have commercial value. Whether because they are naturally better fixed, or long cultivation has more firmly established them, the vine characters of _Vitis vinifera_ more often appear in varieties arising as primary hybrids between that and the native species, and the weaknesses of the foreign grape, which prevent their cultivation in America, crop out. Hybrids in which the vinifera blood is more attenuated, as secondary or tertiary crosses, give better results.

Several secondary hybrids now rank among the best of the cultivated grapes. Examples are Brighton and Diamond. The first is a cross between Diana-Hamburg, a hybrid of a Vinifera and a Labrusca, crossed in its turn with Concord, a Labrusca; the second is a cross between Iona, also a hybrid between a Vinifera and a Labrusca, crossed with Concord. Both were grown from seed planted by Jacob Moore, Brighton, New York, in 1870. Brighton was the first secondary hybrid to attract the attention of grape-breeders, and its advent marked an important step in breeding grapes.

The signal success achieved by hybridizers of the European grape with native species quickly led to similar amalgamations among American species. Jacob Rommel, of Morrison, Missouri, beginning work about 1860, hybridized Labrusca and Vulpina grapes so successfully that a dozen or more of his varieties are still cultivated. All are characterized by great vigor and productiveness; and, although they lack the qualities which make good table-grapes, they are among the best for wine-making. Rommel has had many followers in hybridizing native species, chief of whom was the late T. V. Munson, Fig. 50, Denison, Texas, who literally made every combination of grapes possible, grew thousands of seedlings and produced many valuable varieties.

[Ill.u.s.tration: FIG. 50. T. V. Munson.]

_Improvement by selection._

Selection, continued through successive generations, so important in the improvement of field and garden plants, has played but small part in the domestication of the grape. The period between planting and fruiting is so long that progress would be slow indeed were this method relied on. Moreover, selection, as a method in breeding, is possible only when plants are bred pure, and it is the experience of grape-breeders that in pure breeding this fruit loses in vigor and productiveness and that the variations are exceedingly slight and unstable. Many pure-bred grapes have been raised on the grounds of the New York Agricultural Experiment Station under the eyes of the writer, of which very few have surpa.s.sed the parent or have shown promise for the practice of selection.

_New varieties from sports._

Bud-sports or mutations now and then arise in grapes. But not more than two or three of the 2000 varieties now under cultivation are suspected of having arisen in this way. It is true that mutations seem to occur rather often in grapes, but they are easily confused with variations due to environment and are usually too vague to lay hands on. Until the causes of these mutations are known and until they can be produced and controlled, but little can be hoped for in the amelioration of grapes through mutations.

HYBRIDIZING THE GRAPE

Hybridization has been the chief means of improving the grape. At present, from what is being accomplished by many workers, it looks as if it will long continue to be the best means of improving this fruit.

Since the grape-grower must depend on new varieties for progress, as old varieties cannot be changed, it should be the ambition of growers to produce varieties better than those we now have. Many amateur and professional grape-growers in the past have found breeding grapes a pleasing and profitable hobby, so that much knowledge has acc.u.mulated in regard to manipulating the plants in hybridization, and the results that follow in the offspring of hybridization.

_How to hybridize._

It is a.s.sumed that the reader is familiar with the botany of flowers and the essential principles in crossing plants. If he is not, he must carefully study the structure of flowers, especially those of the grape, so as to be able to distinguish the different organs and to discover when the pollen and stigma are ready for the work of pollination. He should, also, read any one of several current books on plant-breeding.