The plums of New York

Ten states produced over 82 per ct. of the plum crop of the United States in 1899. The census of 1900 shows that in the preceding year the total crop in the country was 8,764,032 bushels of which California, Oregon, New York, Washington, Michigan, Iowa, Texas, Arkansas, Ohio and Kansas, named in order of yield, produced 7,429,248 bushels. All other states yielded 1,334,784 bushels. Of these ten states, three, California, Oregon and Washington, holding first, second and fourth places in production, use by far the greater parts of their crops for prunes. Four others, Iowa, Texas, Arkansas and Kansas, grow the native and Triflora varieties almost exclusively. New York with a crop of 313,668 bushels in 1899, Michigan with 213,682 bushels the same year and Ohio with 81,435 bushels, grew the main crop of Domesticas for the states in which plums are not made into prunes.

At the end of the Nineteenth Century the plum ranked third in commercial value among orchard products, being surpassed by the apple and the peach. The increase in number of trees and bushels of fruit for the whole country for the decade ending with 1899 was remarkable, being for trees 334.9 per ct. and for bushels of fruit 243.1 per ct. These great increases were due to very large planting of plums for prunes on the Pacific Coast and to the widespread distribution during these ten years of native and Triflora varieties. It is very doubtful if the percentage of increase has been nearly so great during the present decade. It is likely that the development of rapid transportation and refrigerator service between the great plum-growing region of the far West and the markets of the East has caused a decrease in trees and production in the eastern states.

Plum-growing, as with the growing of all fruits, is confined to localities geologically, climatically and commercially adapted to the industry. If we take New York as an example we find that plums are grown largely only in ten of the sixty-one counties, according to the census of 1900. These with the number of trees in each are as follows: Niagara 184,133, Ontario 92,917, Seneca 59,205, Monroe 57,246, Schuyler 48,336, Orleans 41,985, Yates 32,742, Albany 32,373, Erie 30,281, Wayne 30,047. Over 62 per ct. of all the trees in the State are in these counties and probably they produce more than 90 per ct. of the plums sent to market.

A canvass of the acreage of four hundred plum-growers in New York shows that the following in order named are the leading commercial varieties: Bradshaw, including Niagara, which is identical, Reine Claude including its several near variations, Italian Prune, German Prune, Lombard, Shropshire, Grand Duke, Washington and Gueii. Abundance and Burbank are as widely distributed as any of these, chiefly owing to the zeal with which nurserymen have sold these varieties, but are seldom grown exclusively in commercial plantations, and their popularity is now on the wane as is also the case with Red June which has been largely planted. Varieties of native plums are hardly grown in New York though now and then they are found in home collections and there are a few small commercial plantations of them.

The fruit of the native and Triflora plums is so inferior to that of the Domestica sorts for market and domestic purposes, that varieties of these are not likely to take the place of the Domestica plums. Producers and purchasers are now familiar with the possibilities of the natives and of the Orientals and have not been greatly attracted by them in New York. It is true, however, that the natives have been chiefly represented by Wild Goose and the Trifloras by Abundance and Burbank—scarcely the best that these groups of plums can produce. It is true, too, that the varieties have been greatly over-praised and that they now suffer from the reaction. Yet the Domesticas command the market and their reliableness in the orchard gives them a popularity in this region which other plums cannot for a long while trench upon.

This brings us to a discussion of the conditions under which plums are now grown in North America and more particularly in New York. Of these, climate, with this fruit, should be first discussed, outranking all others in importance.

CLIMATE

Climatic conditions determine the culture of the plum not only for a region but for a locality; not only as to whether it is possible to grow plums at all but as to whether this fruit can be grown with reasonable prospects of commercial success in competition with other localities. The constituents of climate which are important in plum-growing are temperature, rainfall and air currents, the last two being largely dependent upon the first. The relationship existing between plums and these factors of climate are fairly well known for they have received attention from the very beginning of plum culture.

There are four phases of temperature that need to be considered in order to get a clear insight into the climatic conditions which govern production of fruit crops. These are, the daily, monthly and annual changes in temperature and the extremes in temperature. Of these the daily and annual changes are of little importance. All plants are very adaptable to daily variations in climate and are little affected by them. Annual variations are shown by statements of the annual mean temperatures but such statements are of small value to fruit-growers as they may be the result of averaging very divergent temperatures or temperatures very close together. The monthly mean, however, is a very fair criterion of climate for fruit-growing, especially when given with the amount and distribution of rainfall.

But far more important than any of the above phases are the extremes in temperature and more particularly of cold. A plant can not be grown profitably where the temperature, even occasionally, falls below the point where winter-killing results to tree or bud, or where the blossom is injured by frost. Extremes of heat are disastrous usually only when long continued. For each fruit, too, there must be a total amount of heat available to carry it from the setting of the fruit to maturity, in which respect varieties of any fruit may differ materially. Of the injurious effects and of the necessary amounts of heat, however, we know but little.

These general considerations of temperature lead us to their application to the plum and especially to a discussion of the most important of the several factors—hardiness.

Hardiness to cold, a matter of prime importance with all fruits, is especially so with the plum because of the many different species, each with its own capacity for withstanding cold. As the different species are taken from their natural habitat to other regions, there to become acclimatized, and as new forms originate by hybridization, the matter becomes more complicated and more important. Waugh[145] has investigated the hardiness of plums and we publish a table given by him showing the hardiness of representative varieties of the species most generally cultivated. We have taken the liberty of adding a few plums not given in the original table and have also made some changes in the nomenclature of the groups.

Table Showing the Hardiness of Representative Varieties of Plums at Various Places.

h—hardy; hh—half-hardy; t—tender.

A few general statements in addition to the above table will help to make plain the comparative hardiness of the different groups of cultivated plums. The Nigras may be rated as the hardiest of the plums to be considered though the Americanas are but slightly less hardy. The plums of these species are the hardiest of our tree-fruits and are able to resist nearly as much cold as any other cultivated plant. The Insititias, as represented by the Damsons, at least, come next hardiest after the above species, with varieties of Domestica, as Arctic, Lombard and Voronesh, nearly as hardy. So far as resistance to cold is concerned the Domestica plums as a class are less hardy than the apple, ranking in this respect with the pear. Of the Domesticas the Reine Claude plums are as tender to cold as any though some consider Bradshaw as more tender. Between these last sorts and the hardiest varieties there is a great range in capacity to endure cold, as would be expected with so large a number of varieties originating in widely separated climates. The Triflora plums vary more in hardiness than any other of the cultivated species. Speaking very generally they are less hardy than the Domesticas, the hardiest sorts, Burbank and Abundance, being somewhat hardier than the peach, while the tenderest varieties, of which Kelsey is probably most tender, are distinctly less hardy than the peach. Of the remaining plums, the Hortulana, Munsoniana and Watsoni groups, there are great diversities in opinion as to hardiness. Probably all of the varieties in these last groups are as hardy as the peach with a few sorts in each more hardy than the peach. It is to be expected from the more northern range of the wild prototypes that the Hortulana and Watsoni plums are somewhat hardier than Prunus munsoniana.

The rainfall is of comparatively small concern to plum-growers in America, since, with now and then an exception, in eastern America it is sufficient under proper cultivation, and on the Pacific Coast the crop is largely grown under irrigation. Summarized statements of annual rainfall are of little or no importance since almost all depends upon the distribution of the amount throughout the year and upon the manner in which it falls. Monthly and seasonal “means” of precipitation, as in the case of temperature, may be of considerable importance in determining the desirability of a locality for plums.

Air currents are of local or regional occurrence and though not often the determinant of profitable culture of plums have sometimes been important factors in choosing a location to grow this fruit. The occurrence, direction, moisture condition and temperature are the attributes of air currents usually considered. The failure of many plums to grow in the prairie region of the Mississippi Valley and the Great Plains is no doubt due in some measure to winter winds. The problem of varietal adaptation is more or less complicated in any region by the nature of the air currents.

An extremity of any of the constituents of what we call “weather” endangers the plum crop at blossoming time. In New York stresses of weather are probably the predominating causes of the non-setting of fruit on plum trees which bear an abundance of blossoms. This is well shown in a study of the relations of weather to the setting of fruit made by the New York Agricultural Experiment Station in which it is held that several phases of weather at blossoming time cause the loss of plum crops.[146] Thus late frosts, wet weather, low temperature, strong winds and wide daily ranges in temperature were factors in the loss of fruit crops in all of the failures during a period of twenty-five years. Quite as significant was the fact that in all of the years during this period when there was sunshine and warm, dry weather during blossoming time there were good crops of fruit.

Locations for growing the different varieties of plums are selected with reference to general and local climate. As regards general climate, latitude, altitude and proximity to large bodies of water are the chief determining characters; as regards local climate, the lay of the land has most to do as a determinant. Again, varieties are selected with reference to time of blooming, that they may escape in some degree injurious climatal agencies. Lastly, varieties are selected having greater capacity, from one cause or another, to withstand injurious weather. With all varieties it is found that cultural treatment to induce strong vitality helps a tree to withstand stresses of harmful weather at blossoming time.

The above considerations show that the blossoming dates of plums should be known for the proper culture of this fruit. In the following table averages of the blooming dates of varieties of plums for the eight years just past, 1902 to 1909, inclusive, are given.

In making use of these dates, consideration must be given to the environment of the orchards at Geneva. The latitude of the Smith Astronomical Observatory, a quarter of a mile from the Station orchards is 42° 52′ 46.2″; the altitude of the orchards is from five hundred to five hundred and twenty-five feet above the sea level; the soil is a stiff and rather cold clay; the orchards lie about a mile west of Seneca Lake, a body of water forty miles in length and from one to three and one-half miles in width and more than six hundred feet deep. The lake has frozen over but a few times since the region was settled, over a hundred years ago, and has a very beneficial influence on the adjacent country in lessening the cold of winter and the heat of summer, and in preventing early blooming.

The dates are those of full bloom. They were taken from trees grown under normal conditions as to pruning, distance apart, and as to all other factors which might influence the blooming period.

An inspection of the table shows that there is a variation of several days between the time of full bloom of the different varieties of the same species. These differences can be taken advantage of in selecting sorts to avoid injury from frost. The same table shows the ripening season of the plums growing on the Station grounds. Now and then the late and very late plums given in the table may be caught by fall frosts in the colder parts of New York or in regions having a similar climate.

Table Showing Blooming Dates and Season of Ripening.

The “blooming date” is that of full bloom.

Under season of ripening “very early” is from July 15 to August 10; “early,” August 10 to August 20; “mid-season,” August 20 to September 10; “late,” September 10 to September 20; “very late,” September 20 to October 1.