The plum is also one of the anciently cultivated fruits of central Asia. Regel says in the Gartenflora, published in Berlin: "The common plum of the district of Tashkend and of the more elevated settlements of the southern territory is the beautiful Bokharan variety. It is particularly abundant in Karaegin, and may be found also in the middle district of the Paendsh valley."
Henry Lansdell, D.D., also spent much time investigating the fruits of central Asia. He reports finding an apricot-tree five feet and three inches in diameter of stem, and plums that were red, yellow, and black, "particularly well flavored," on October 11th.
De Candolle says: "It is very doubtful if Prunus domestica is indigenous in Europe. Authors who have seen the species in the east do not hesitate to say that it is 'subspontaneous."
Some of the Asiatic plums seem to have been first introduced in Europe and planted on the Volga bluffs, as their culture there we were told goes back to the early history of that region. But varieties of the Prunus domestica type have been so long cultivated in west Europe that the race has changed in leaf, bud, and fruit materially from that found at this time in central Asia, which we know more nearly resembles the Chinese and Japanese plums (Prunus triflora). Several of the Russian plums we met with on the Volga had the triple bud, leaf, and pasty flesh of the Japan varieties, and we met with plums at the great fair at Nishni Novgorod in 1882, that exhibited all the characteristics of the triflora and domestica species. Hence it can easily be believed that central Asia had two species or races of the plum or that one original species differentiated as it spread east and west from one centre. But the writer personally believes from varied evidences that central Asia had, in prehistoric times, two species. Not the least reason for the belief is that we have found it easy to cross the Japan varieties with our native plum (105. Nearly Allied Crossing), but we have not been able to cross the Americana varieties with any variety tried of the domestica race.
The domestica varieties of west Europe and their American seedlings are mainly grown commercially on the west coast. It is estimated by Stubenrauch that the acreage of the plum and prune reaches a total of 55,000 acres, of which seven-eighths is in prunes in California. The domestica varieties are also grown quite extensively in the Eastern States and in Michigan. In fact, in the Southern States, the arid States, and the prairie States, certain varieties are starred or double-starred locally by the American Pomological Society. In the northern part of the prairie States the advent of the Russian plums has extended the culture of the domestica race farther north without loss in size or quality.
The Japan plums (Prunus triflora) have only been introduced within recent years, but their culture has been extended very rapidly in the lake region, in the South, and indeed in all the States where they have proven hardy. These Oriental varieties come into bearing earlier than the European sorts and, as a rule, mature their fruit earlier in the season. Usually they are rounder in form and the colors run to red and yellow. They sell well in market, but for dessert use at home and culinary purposes they are not equal to the best European or Russian varieties, as they lack in sprightliness and richness of flavor.
Selected varieties of the native species of the North (Prunus Americana) and of the Chickasaw races of the South, have rapidly come to the front for general culture in the prairie States and to a large extent over the Southern and Eastern States.
In estimating the quality of our best native plums under culture, we need some new rules for judging. They have a juiciness and sprightliness peculiar to the race, and an invalid can eat, when fully ripe, several of them with satisfaction and without affecting a weak stomach, as do all the foreign varieties. Professor Goff also says truly: "The choicest varieties, peeled and served fresh, are equal to the finest peaches." Served on the table in this way they can be eaten freely by those who are obliged to use ripe foreign plums and prunes with care and in less quantity.
For culinary use, if peeled and the pits rejected, such varieties as Wyant, Hart's De Soto, Surprise, and Brittle-wood are superior in some respects to the domestica or Japan varieties for daily use. At first the decision of all educated palates will be in favor of the sweeter and richer foreign fruits. But the pleasant fruit-acid of the native soon wins favor, and it can be eaten as freely as the strawberry or grape without the after effects of the free use of the foreign sorts.
Another class of American plums is beginning to attract attention. As noted in section (105. Nearly Allied Crossing) the Americana varieties cross readily with those of Japan and produce a desirable union of the good points of each. The pasty flesh of the Japans is given more juice and character in the hybrids and the thick skin of the natives, with more or less acridity, is changed in texture and materially thinned, yet not enough to prevent safe transportation. To an extent not usual in hybridizing, about all the hybrids yet produced have crisp, tender, juicy flesh with a perceptible flavor of the Japan varieties. The prepotency of the native species seems in every case to determine the hardiness of the hybrids produced, while the Japan species modifies and improves the fruit.
The Chicasa or angustifolia and liortulana species of the South have given us by selection and crossing some valuable varieties, such as Forest Rose, Maquoketa, and Golden Beauty, and some fine crosses with the Americana and triflora species.