The native species (Diospyros Virginiana) is indigenous to all parts of the Southern States known to the writer, and along the streams it, in some cases, extends north to the 40th parallel. The fruit of the best varieties is small as compared with the Japan varieties, which often weigh half a pound, and large specimens often weigh from ten to twelve ounces. The largest of the native varieties tested by the writer has been less than two inches in diameter and well loaded with seeds. Yet prior to the advent of the Japan varieties some of the best native sorts were locally prized in the South and propagated by nurserymen.
No horticultural work would prove more interesting and possibly valuable than crossing the seedless varieties of the South, with fruit one inch in diameter, with the seedless Japan (Tanenashi), with fruit three and one half inches in diameter. Such hybrids would be apt to follow the natives in hardiness, as our native is nearest to Nature (104. Advance Planning of the Work), and the probable seedless fruit may be of medium size and improved flavor. Such a variety might become specially valuable for drying.
As yet, drying the best ripe Japan persimmons has been experimental, but the decision of experts has been in its favor.
A testing committee in several instances has decided that the dried persimmons were far better in quality and more nutritious and healthful than the best Smyrna figs.
Another line of improvement would be in the way of importing hardier varieties from northern Japan and from central Asia. The writer does not know the extent of persimmon-growing in central Asia, but at the Nishni Novgorod fair we were told that the fruit attained large size and was dried for commerce and home use in great quantity. Regel says: "The date plum in the warmer district of Darvas becomes a large tree." This would indicate it to be a different species from that of the varieties we have from Japan. As Darvas is on the 40th parallel and far into the interior of the continent, we may safely believe that their cultivated varieties would prove much hardier than those from the Japan island in the Gulf stream on about the same latitude. It would now be easy to secure the varieties grown in central Asia and it would prove interesting if not profitable to cross them with the Japan varieties.
The native persimmon is easily propagated for stocks from the seeds planted early in the South or later, if the seeds are stratified. Select native varieties and the Japan sorts are collar-grafted upon the seedlings. But it is best to transplant the seedlings to nursery rows before collar-grafting is done, as it gives a better root system. Budding is also practised, but this should be on transplanted stocks. If budded or grafted where the tap-roots went down from the seed they are difficult to transplant successfully.
Top-working the native species as it stands in orchard, or growing wild, is often practised profitably. Even in the pine barrens of Florida the top-grafted Japan varieties have formed fine heads and borne heavy crops.
The native varieties are usually dioecious (34. Monoecious and Dioecious Flowers); but the best Japan sorts are monoecious, or at least most varieties have enough staminate flowers for pollination. Yet it has been proven that the best crops are obtained by intermingling varieties, with the result of varying the fruit to some extent by cross pollination. That is, the varieties with red flesh are often half red and half brown, or some other shade, on the same tree.
The continued heavy crops after the trees come into bearing dwarfs the trees so that they make small annual growth. Hence the usual distance apart is about the same as for dwarf pears, from twelve to fifteen feet each way. Yet isolated trees first planted in the Southern States we have seen from thirty-five to forty feet in height, with spread of branches like a Southern pear-tree of the Japan type. The fruit is borne on the new growth mainly, hence the pruning is in the way of taking out the dead wood and thinning the inner branches.