Bulletin: Volume 1, Issue 3
At request of Prof. J. L. Budd an investigation has been made into the composition of certain varieties of apples, of which some are well known throughout the State, others are being introduced by Prof. B. from his Russian. stock, and still others are undergoing trial on the College grounds. All the samples analyzed were grown, in this vicinity, and the few not from the College grounds were contributed by Mr. A. Graves of Ames.
The chief value of apples and fruits in general, in man’s dietary, lies not in the nutrition which they furnish, for they are poor in nutritive elements, but rather in those constituents which gratify the senses of taste and smell, sharpen the appetite, promote digestion, and in other ways contribute to his health and pleasure. Such costituents are the vegetable acids and their salts, volatile oils and ethers (imparting flavor and odor), the “pectous substances” and gums (imparting viscosity and jelly-like consistence), sugars, including the glucoses (dextrose or grape sugar and levulose or fruit-sugar) together with sucrose or cane-sugar, and possibly other substances as yet but imperfectly known. Beside these, the water of fruits is an important constituent, imparting juiciness and serving to hold in solution the tasteful and healthful materials just named.
In treating of the following injurious fungi only such facts in regard to their manner of growth are mentioned as is necessary to enable one to apply intelligently the given remedies. A few preliminary remarks therefore concerning fungi as a class will be useful.
First, fungi are true plants which originate from spores, often of more than one kind, which answer the purpose of seeds, but which are much simpler in structure. Where no spores are present therefore no fungus or fungus disease can appear, any more than weeds can grow where no seeds have been allowed to ripen. Fungi however produce spores eyen more abundantly than weeds produce seeds, and there is hardly a locality in which fungus spores of some kind are not present. Many fungi however are limited to particular localities, and spread to other regions only when the spores are accidentally introduced, or when the plants upon which they live are introduced for cultivation. Thus the grape rot, which is common through the Eastern States, is still unknown in many parts of the country, and it has but recently been accidentally introduced from this country into France, where it threatened, until checked by artificial remedies, to seriously interfere with grape culture in that country. Many similar examples could be given.
The winter of 1884 and 5 and the remarkable drouth of 1887, destroyed all of the apple orchards in Iowa, except in a few localities, where natural drainage and a very porous condition of soils, favored constant growth during the summer seasons. All of our American apples, as well as all of the apples from western Europe, have proved much too tender on ordinary prairie soils. But the Duchess of Oldenburg, Tetofsky and a few other varieties of the apple from Russia, have endured the most trying tests in all parts of the state without being harmed. As Iowa farmers are anxious to plant new orchards again, as soon as they shall be assured that their late losses will not be repeated, I will give the results of my observations and experiments in Northern Iowa since 1866; which may be of much value to many who have given but little attention to the nature and wants of different kinds of trees. If apples had not been disseminated over many degrees of latitude and longitude in Europe, Asia and America; it is probable that there would have been but few varieties, now. But they were scattered widely over the face of the earth, and as they were taken farther and farther north, they acquired new characteristics which enabled them to endure more degrees of cold. And when they were moved to places where the climate was much dryer and hotter, or moister than the one to which they were adapted, changes were effected in them after several generations, which adapted them to the unfavorable conditions which surrounded them. That I may be clearly understood, while describing the effects of unfavorable climatic conditions upon trees, I will explain the structure of trees and the principles of plant growth very briefly. All of the differents parts of trees and herbaceous plants are composed of cells. A living cell is a very small, porous and elastic sack like a bladder; which contains a semi-fluid substance called protoplasm and assimilated cell sap. After growing for a short time, each cell is divided into two parts or two new cells, each of which again divides and thus growth proceeds, forming webs of cells, which are spread one upon another during the growing season. As the webs of cells become covered w7ith webs of newer cells, their walls grow thicker; they lose their protoplasm, their ends become perforated and unite, and they are converted into tubes. Of indefinite numbers of such tubes bundles are formed, causing ducts or air passages between them. Through such ducts in the sap wood of trees, the crude sap is taken from the roots to the leaves. The pith and medulary rays are used as store rooms for reserve food materials, from which new leaves will be formed during the following spring; or they may be used to support growth when the regular supplies of assimilated sap are cut off by drouth or other causes. The wood cells of a tree which have been formed in a single season, constitute the sap-wood. The protoplasm not only constructs sap-wood during the growing season, but it forms a new inner bark, by a process similar to that which was used in the formation of sap-wood. At the same time, the old inner bark is converted into new green bark and the old green bark is changed into corky bark. The lives of cells are of very short duration. In fact, the only living cells in the limbs, body or roots of a tree, are those which contain protoplasm. Except at the tender terminal points of growth, they are formed only on the outside of the sap wood and on the inside of the inner bark, and constitute what is called the cambium layer. Therefore, all the cells of a former season’s growth are dead and worthless, for all purposes, except conducting-fluids, and supporting more elevated parts of the tree. Then it is not difficult to understand, that the seat of life is in the very thin cambium layer, between the sapwood and bark of trees; that life is really in the semi-fluid protoplasm of the billions of working cells in this layer, and that all growth takes place here. When the atmosphere becomes sufficiently warm in the spring, the protoplasm becomes active at all points between the sap wood and the inner bark of trees, and new leaves are formed from reserve food materials, which were stored up in the medulary rays and pith, near the close of the previous seasons’ growth. As soon as the leaves become sufficiently developed, a green substance called chlorophyll is formed in them by rays of light, which is always combined with particles of protoplasm.
In this state where corn is king other productions are apt to be neglected, or looked upon as of minor importance when compared with the great staple. Twenty years ago wheat was Iowa’s most paying product. In course of time it has given way to corn. Will the soil continue to produce corn indefinitely? Taking this question into consideration every thoughtful farmer will realize the important position which the grasses hold in agriculture, and the importance of selecting the best varieties for green manuring pasturage, and hay. On turning to our present list of grasses we find it very limited in variety. Again all the best ones are of eastern or European origin, introduced from different places and called tame grasses as soon as put under cultivation, though they were once wild grasses and are still such in their native homes. It might be said that the general list of grasses is not a limited one; but the question of local adaptation coming in sifts out so many that it makes the list comparatively limited for particular localities; even our standards clover and timothy do not show perfect adaptation, fall pasturing injuring the former, while the latter is often unprofitable when sown alone and is frequently affected with fungus diseases. The question then arises can we not select from the native grasses of this state, or from the states and territories west and north of our boundaries, the richest pasture lauds of America, varieties which will increase the number of our hay and pasture plants.
To obtain improved varieties of fruits which shall be hardy in Iowa, several thousand successful crosses were made during the past season, mostly upon apples. About one thousand seeds of these crosses, representing nearly fifty varieties, are now preserved in damp sand to be planted next spring. The crosses were mainly of the best American winter apples upon Russian varieties growing at the College. In this work I was aided by the Director’s assistant, Mr. John Craig, and by the following students of the Agricultural College: Mr. F. W. Mally, Mr. J. G. Abraham, Mr. E. A. Sheafe, Mr. Albert McClelland, and Mr. Fred L. Lightner. The selection of the varieties to be crossed was made by the Director and Prof. J. L. Budd. Thanks are due to G. B. Brackett, Denmark, Iowa, N. K. Fluke, Davenport, Iowa, John Saul, Washington D. C., O. R. L. Crozier of Ann Arbor, Michigan, and others, for" pollen which they kindly furnished.
It is not expected that all the crossed varieties will prove worthy of propagation, but it is believed that a much larger percentage will possess the desired qualities than with chance seedlings. The young trees will be carefully studied, and those found sufficiently hardy and vigorous will be grafted on older stocks to bring them into bearing at an early date.