This section is from the book "The Gardener's Monthly And Horticulturist V26", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
I send you by this mail the tips of scions just cut from two trees of New American and Down-ing's Improved mulberry, which stand in an exposed position on the ridge near our office. The pith of these scions, you will notice, is not discolored, and it is worthy of remark, that, aside from other cold weather, we have had it 160 below zero this winter, and I think this " counts one," in favor of the hardiness of these closely allied varieties. The trees have stood in grass most of the time for fifteen years - have not been manured, and have been abused by constant close cutting for buds and scions. The New American is our favorite. It regularly produces full crops of fruit, from one to two inches long, over a bearing season of six weeks. The fruit is jet black when ripe, and is easily gathered by shaking the tree over sheets. The New American is a stronger grower than the Downing, and the young trees are better in many ways. Either one of these varieties is ornamental, has large, entire leaves, and is most satisfactory in every respect.
While I am on this subject, I wish to say that I think the Russian Mulberry (so called) is, if not a "fraud," no better in any respect than the Morus alba, a variety of which it is said to be.
We have the "Russian," growing aside the Morus alba, and can see no difference in the growth, hardiness, or in any other respect. They are not distinguishable. A friend of mine has fruited the "Russian," and in every way it corresponds exactly with a dozen famous mulberry trees which have stood for thirty years on the campus of Hobart College. Geneva, New York.
[It is worth remembering that hardiness in a mulberry, and in many other things, is not a question of temperature - it is a question of vital power to resist evaporation. When a plant loses its power to resist evaporating influences, it dies. Hence, many plants live through some winters or in some localities where the thermometer is very low, when the atmosphere is moist and cloudy, that would die under a much higher temperature when under bright light or dry atmosphere; and again, when the vital power of a plant has been weakened by long culture under unfavorable conditions, it will die under precisely the same circumstances through which a healthier stock will live. For instance, Morus multicaulis, a variety of Morus alba, was hardy enough when first introduced - but under the forcing methods to propogate enormously, its vital power weakened, and then it was it became "tender," and "diseased." It will be found just so with any other variety of silk-worm mulberry; all of which are varieties of Morus alba. They are all as " hardy as a rock," in the general sense.
We doubt whether any one can claim hardiness over another, until its power of resistance has been weakened by a succession of unfavorable influences.
The specimens sent had certainly got through this winter very well. - Ed. G. M].