CHAPTER VI.

FILBERT OR HAZELNUT.

Corylus, _Tournefort_. Name from _korys_, a hood, helmet or bonnet, in reference to the form of the calyx or husk enclosing the nut. Order, _Corylaceæ_. Deciduous trees or low shrubs. Male flowers appearing in the autumn in pendulous cylindrical catkins two inches or more in length, with a two-cleft calyx partly united with the bracts or scales. These catkins remain on the plants all winter, becoming fully developed, and shedding their pollen early the following spring. Female flowers minute, entirely hidden within the buds during the winter, but early in spring their bright red, thread-like stigmas push out from the tips of the lateral or terminal buds. Ovary two-celled, with one ovule in each. Nut globular, ovoid or oblong, often in clusters, but each enclosed in a leafy, two- or three-valved husk, fringed or deeply notched at the upper end. Leaves broadly heart-shaped, serrate, with sturdy, short leaf-stalks. The filbert and hazel always bloom before the leaves appear in spring, and the male catkins usually open and begin to scatter their pollen in this latitude during warm days in March, the females soon following, their bright-red stigmas pushing out from the ends of the buds, but as soon as fertilization has been consummated they shrivel and disappear. The trees may then remain leafless for weeks following, and yet produce a heavy crop of fruit.

The common English name, filbert, is from "full-beard." All the varieties with husks extending beyond the nut, and with fringed edges, are filberts (Fig. 37); while those with husks shorter than the nuts (Fig. 38) are hazels, from the old Anglo-Saxon word, _hæsel_, a hood or bonnet. The parentage, size, form or quality of the nut, is not to be considered in this classification, for when the nuts are ripe and fallen from the husks, there is nothing left to distinguish the hazelnuts from filberts, unless a person is sufficiently familiar with a variety to know to which group it belongs. In France these nuts are known under the general name of _Noysette_; while in Germany it is _Haselnuss_; in Holland _Hazelnoot_; and in Italy _Avellana_, from Avellana, a city of Naples, near which there is a valley where these nuts have been extensively cultivated for many centuries.

=History of the Filbert.=--It is claimed that the filbert was first known to the Romans as _Nux Pontica_, because introduced from Pontus; but it must have become naturalized throughout southern Europe in very early times. But the Italian name of _Avellana_ appears to have been applied to the wild hazel of Britain, long before Linnæus adopted it as the specific name of the indigenous species. John Evelyn, one of the most careful and learned of English arboriculturists of his time, in referring to these nuts, in his "Sylva," 1664, says: "I do not confound the filbert Pontic, distinguished by its beard, with our foresters or bald hazelnuts, which, doubtless, we had from abroad, bearing the names of _Avelan_ or _Avelin_, as I find in some ancient records and deeds in my custody, where my ancestors' names were written Avelan, _alias_ Evelin."

The filbert has been celebrated in prose and poetry from ancient times, as we may infer from a remark of Virgil, who says that it has been more honored "than the vine, the myrtle, or even the bay itself" (Eclogue vii).

The supposed occult power of a forked twig of the hazel as a divining-rod (_virgula divinatoria_) for finding hidden treasures, veins of metals, subterranean streams of water, and even pointing out criminals, is, of course, purely mythical, although so solemnly attested by many learned men in the past; and I would not consider this myth worthy of a notice here were it not for the fact that it was early imported into this country, and is still firmly believed by many persons among our rural population. It is true that the supposed attributes of the European hazel have been transferred to different plants in this country, mainly to the peach and our indigenous witch-hazel (_Hamamelis Virginiana_), but the myth still lives, a legitimate descendant of an Old World nut tree.

There is little to be said in regard to the history of the filbert and hazelnut in this country, but it is quite likely that both of the European species, and many varieties, were brought here and planted by the early settlers in the Eastern States, and bushes of the same could have been seen in many gardens a hundred years ago; but I have been unable to find any account of extensive plantings of these nuts, although nurserymen, all along, have been offering choice varieties to their customers. In the main, our pomologists have either remained silent in regard to these nuts, or, at most, referred to them very briefly in their published works.

William Prince, of Flushing, N. Y., in a "Short Treatise on Horticulture," published in 1828, refers to the filbert as follows:

"This shrub or, in some cases, tree, accommodates itself to every exposition, and to every variety of soil, but prefers a moist loam on a sandy bottom, with a northern exposure. It is easily multiplied by seeds, layers or inoculation. In fact, these nuts, which are vended in large quantities in our markets, grow as well in our climate as the common hazelnut, and produce very abundantly. Such being the case, it is hoped, ere long, sufficient will be produced from our soil to supersede the necessity of importation, as plantations of this tree would amply remunerate the possessor; or if planted as a hedge, would be found to be very productive. A single bush of the Spanish filbert in my garden has produced a half-bushel annually."

Mr. Prince then names a few of the best varieties, which are about the same as those recommended at the present time, and he was, no doubt, honest in recommending filbert culture to his countrymen, for his own limited experience proved that the trees would grow here and fruit abundantly.

A. J. Downing, in the first edition of his "Fruits and Fruit Trees of America," 1845, says: "The Spanish filbert, common in many of our gardens, is a worthless, nearly barren variety; but we have found the better English sorts productive and excellent in this climate (Newburg, N. Y.), and at least a few plants of these should have a place in all our gardens." If a few plants will succeed in a garden, then we might reasonably suppose that the number might be safely increased, and this was the idea of Mr. Prince, and many other writers on the subject since his time, but I fail to find any record of extended experiments with these nuts in this country, and as there must be some good reason for this neglect, perhaps my own experience in the cultivation of the filbert and hazel, to be given in succeeding pages, may throw some light on this question.

=Propagation.=--Filberts are readily propagated by almost all the modes employed in the multiplication of ordinary fruit trees and shrubs. The nuts are not at all delicate, and may be planted in the fall, or stored in a cool place, mixed with sand or sphagnum, and then put out in spring, always selecting a rather light and rich soil for a seed bed, and in such beds plants from one to three feet high may be obtained the first season. The seedlings produce such a mass of fine roots that they are readily transplanted without danger of loss. Varieties are perpetuated and multiplied by budding, grafting, suckers, layers, and some grow quite readily from cuttings made of the young, vigorous shoots, cut up into proper lengths in the fall, and then buried in the ground until the following spring, then planted out in trenches, as usually practiced with currants, grapes and similar plants. The method of propagation most generally practiced in Europe and this country is by suckers, and as the cultivated varieties of the filbert usually produce these from the base of their stems in profusion, there is no lack of material; besides, they make as strong, healthy and productive plants as can be procured in any other way. To secure an extra number of roots on these suckers, they should be banked up with a few inches in depth of good rich soil, or old manure, about midsummer, and then late in the autumn dig down to the base and remove with knife or chisel, after which they may be headed down to about fifteen or eighteen inches, and heeled-in for the winter, to be planted out in nursery rows early in spring. If a greater number of sprouts are wanted than the plants naturally produce, the main stem may be cut down; but this will seldom be necessary, because the young transplanted suckers will usually produce more or less new ones the first season, all of which can be utilized for multiplying the stock if they are wanted.

=Soil, Location and Climate.=--European varieties of the filbert thrive best in what may be termed a rich loam, with a dry subsoil. If the soil is too moist, the trees are inclined to run too much to wood, producing less fruit. In the famous nut orchards of Kent, England, the soil is loam upon a dry, sandy rock. The trees in these orchards are manured at least once in two years, especially after they reach the full bearing age. Almost any good soil that is rich enough to produce a good crop of corn, and is not submerged in winter, will answer for the filbert in this country.

In selecting a location for a filbert orchard, an open, airy one would probably be preferable to a spot so sheltered as to cause the flowers to appear so early as to be injured by frosts. Furthermore, I would warn cultivators to keep as far away as possible from any hedgerows or plantation of the wild native hazel bushes, for these are always loaded with disease germs that are fatal to the foreign species. We might reasonably suppose that filberts would succeed better in the Southern than in the Northern States, but if the experience of those who have tried them there count for anything, then these nuts are not adapted to the South, owing to the fact that the flowers almost invariably push out during warm days in winter, and these are destroyed later by frosts. In the more elevated regions of the northern border of the Southern, and in similar locations in the Middle States, these nuts will doubtless thrive, or at least the climate will prove congenial. The more equable the climate and free from extremes in temperature, the better; but the most important element in this country is moisture, especially in summer, when the nuts are filling out; and the best way to supply this, where irrigation cannot be practiced, is to keep the ground around the trees continually covered with a mulch of leaves or other coarse vegetable matter.

=Planting and Pruning.=--The space to be allowed between the plants, when set out for bearing, will, of course, depend very much upon the size they are expected to attain. Those varieties which assume and remain in the bush form may be planted very close together, or not more than six to eight feet between the plants; but those which become small trees must be given more room. The larger European sorts, which are at present the only ones worth cultivating for their nuts, should be set ten or twelve feet apart, and the rows fifteen to sixteen feet, then if properly pruned they will shade the ground and be in a convenient form for gathering the crop. The trees may be planted in the orchard when quite small, and some kind of vegetable crop grown among them for the first two or three years, but I would prefer keeping the plants in nursery rows until they were four or five feet high, and then transplant to the orchard, and set a short, stout stake by the side of each, to keep the main stem in an upright position until the tree is well established.

The first pruning,--except removing suckers from those in the nursery rows,--will be the heading back of the main or central stem to a hight of two or three feet, for the purpose of laying the foundation, as it were, of the head of the future tree. Three or four of the larger branches, which will push out from near the top of the severed main stem, are to be selected to form the top, and all others removed. Small lateral branches or twigs will spring out from the larger or main ones, and in this way the head of a bearing tree is formed. But before attempting to prune a mature or fruitful tree, we must consider the mode of fructification, for the filbert does not bear nuts on the young growth of the season, as in the chestnut, but on the small branchlets or spur-like twigs of the preceding season, or, as we may say, on the one-year-old twigs. The small fruiting twigs are seldom more than four to six inches long, and sometimes almost every well-developed bud on these contain pistillate flowers and embryo nuts, either singly or in clusters. In pruning the bearing trees, the main point to be observed is to head back the strong leading shoots, to prevent the trees growing too tall, as well as to force out the side or lateral twigs as fruiting wood for the ensuing year. If the heads of the trees become too much crowded to admit light and air to the center, some of the larger branches must be removed entire. The best time to prune is in early spring, when the trees are in bloom, for at this season we can readily determine the injured from the sound male catkins, and preserve enough of these to insure perfect fertilization. It is not necessary, however, that there should be healthy pollen-bearing catkins on every tree in an orchard, for if one in a dozen is well supplied, there will be sufficient to fertilize the flowers of all growing near by. It often happens, in our rather severe climate, that the catkins of some trees or varieties are winterkilled, while the pistillate flowers enclosed in the buds escape injury, and when this occurs it is well to have some hardy variety at hand, from which pollen can be obtained when needed. The inferior varieties are usually the most hardy, and the wild European hazel or our northern beaked hazel, will usually escape injury where all the large improved sorts fail, and it requires but a few minutes' labor to cut branches bearing sound catkins, and scatter these about through the heads of trees requiring such assistance to make them fruitful.

SPECIES OF AMERICAN HAZELS.

CORYLUS AMERICANA (Walters). Common hazel bush.--Leaves roundish, heart-shaped, pointed, coarsely serrate; husk somewhat downy, with a wide, flattened, fringed border extending beyond the roundish nut. Shell rather thick and brittle; kernel sweet and good, but the nut is too small to be considered of much value. A low shrub, with many stems springing from the roots. Young shoots and twigs downy and glandular-hairy. Common in woods and old fields from Canada to Florida.

CORYLUS ROSTRATA (Aiton). Beaked hazel.--Leaves ovate or oblong, somewhat heart-shaped, pointed, doubly serrate; husk extending an inch or more beyond the round or ovoid nut, forming before it opens a long tubular beak, hence the name. The husk is densely covered with nettle-like bristles, which are quite irritating to tender hands. The nuts are small, usually growing in clusters at the ends of the twigs, only a few coming to maturity. A low shrub or small tree, usually growing in a dense clump, not spreading from subterranean stems, as in the last species. Common on rather firm and rich soil along the borders of streams, in the northern border States, and southward on the Alleghanies, but most abundant in the north through Canada, and westward to the Pacific in Washington and Oregon, where, in the mountains, it often assumes the tree form, growing to a hight of twenty-five to thirty feet, with a stem from four to six inches in diameter. The wood is light, soft, and very white to the center. It also extends southward to central California, but here it is only a small bush, this form having been described under the name of _Corylus rostrata_, var. Californica, A. de C. This species probably reaches its highest development in the Cascade range, in northern Oregon. The same or a closely allied species of the hazel extends far into northern Asia. There are no improved varieties of either of our native species of the hazel in cultivation.

EUROPEAN SPECIES OF CORYLUS.

CORYLUS AVELLANA (Linn.). Common hazelnut.--Leaves roundish, heart-shaped, pointed, coarsely and unevenly serrate; husk bell-shaped, spreading, with a fringed or deeply cut margin. The original form of this nut is supposed to have been ovate or oval, but with a plant indigenous to such a wide range of climate and country, and one that has been so long under cultivation,--running wild in many localities where it is not a native,--it would be very difficult at this time to determine its primary botanical characters. A common shrub or small tree throughout the greater part of Europe and Asia.

CORYLUS COLURNA (Linn.).--Constantinople hazel. Leaves roundish ovate, heart-shaped; husk double, the inner one divided into three deeply cleft divisions, the outer with many long, slender, curved segments, giving to the calyx or husk a fringed appearance, but leaving the end of the nut fully exposed (Fig. 39). Nuts small, and for this reason rarely cultivated. Native of Asia Minor, where the tree attains a hight of from fifty to sixty feet. It is, however, hardy in France and England, and was introduced into the latter country some three hundred years ago, probably by Clusius, who received either nuts or plants from Constantinople, hence its present name.

There are several other hazels and filberts, so distinct from the two common European types that botanists have, in a few instances, been inclined to elevate them to the rank of species, and among these I may name _Corylus heterophylla_, or various-leaved filbert, from eastern Asia, also the _Corylus ferox_, or spiny filbert, which has a long and deeply cut or fringed husk. It is a native of the Sheopur mountain in Nepaul. But from the two common European species, _C. Avellana_ and _C. Colurna_, and their hybrids, many hundreds of varieties have been raised, and from among these we may readily select a dozen possessing all the distinct and estimable properties to be found in this genus of nut-bearing plants; to multiply names without securing anything of intrinsic value, is but a waste of time and labor on the part of the cultivator.

As we have no popular varieties of American origin, I am compelled to consult European catalogues in making a selection of those most promising for cultivation here, and this is, perhaps, an advantage, inasmuch as our transatlantic cousins have had a long experience and abundant opportunities for determining the merits of the varieties they recommend. If hardiness and adaptation to our soil and climate are to be taken into account, in making a selection, then we may fail for the want of experienced guides, as it is undeniable that very few persons in this country have ever attempted to conduct extended experiments in the cultivation of either the native or European species and varieties of the hazel.

Taking this view of the situation, I shall avail myself of the small but select list of varieties given in that standard work, "The Dictionary of Gardening," edited by Mr. George Nicholson, of the Royal Gardens, Kew, England.

SELECT LIST OF VARIETIES.

ALBA, OR WHITE FILBERT.--Considered in England one of the best varieties in cultivation. From the peculiar structure of the husk, which contracts rather than opens at the outer edge, this filbert can be kept longer in its cover than most others. As fashion demands that fresh filberts must be brought to the table in their husks, this variety deserves special attention. It is also known as Avelinier Blanche, Wrotham Park, etc.

COSFORD, OR MISS YOUNG'S THIN-SHELLED.--Nut oblong, of excellent quality; husk hairy, deeply cut, about as long as the nut. Highly valued on account of the thinness of the shell.

CRISPA, OR FRIZZLED FILBERT.--Shell thin, somewhat flattened; husk richly and curiously frizzled throughout, open wide at the mouth, and hanging about as long again as the nut. Ripens late, and one of the most productive.

DOWNTON LARGE SQUARE.--Nut very large; shell thick and well-filled; husk smooth, shorter than the nut. A peculiarly formed semi-square nut, of the best quality.

LAMBERT'S FILBERT (_Corylus tubulosa_).--Nut large, oblong; shell thick and strong, the kernel being covered with a red skin; husk long, rather smooth, serrated at the edges, longer than the nut. A fine, strong-growing, free-fruiting variety. It is quite popular in California, where it has been in cultivation for twenty years or more under the name of Red Aveline. Specimens I have received from there were not as large as those raised in England, but this can be accounted for by the difference in climate. This variety is cultivated in Europe under various local names, as, for instance, Great Cob, Kentish Cob, Filbert Cob, and Large Bond Cob.

GRANDIS, OR ROUND COB-NUT.--Nut large, short, slightly compressed, very thick and hard; husk shorter than the fruit, much frizzled and hairy. This is supposed to be the true Barcelona nut of commerce, and is one of the finest grown. This is the large round hazel or filbert so largely imported for the trade in this country. It has many synonyms, and among them we may record Downton, Dwarf Prolific, Great Cob and Round Cob.

PURPLE-LEAVED FILBERT.--Usually cultivated as an ornamental shrub in this country, but under proper treatment it is one of the most valuable for its fruit. Leaves very large, and of a deep purple color. Nuts and husk of the same color, which they retain until cut by frosts. Nuts large, an inch in length; husks much longer than the nut, and slightly hairy. The catkins are tender and become winterkilled in our Northern States, but if the pistillate flowers are fertilized by pollen from some more hardy plant, this purple-leaved filbert is exceedingly prolific. I have gathered eighty nuts from a small bush in my garden, the flowers of which had been fertilized from another variety in early spring.

RED FILBERT. Red Hazel, Avelinier Rouge.--Nut medium ovate, not long as in the _tubulosa_, or Lambert's filbert; shell thick; husk long and hispid. A very productive variety of good quality.

SPANISH FILBERT.--Nut very large, oblong; shell thick; husk smooth, longer than the nut. A very large variety, sometimes confounded with the Round cob-nut and its synonyms.

PERSONAL EXPERIENCE WITH FILBERTS.

Believing that our failures are often of far more value, in the line of education, than our successes, I shall not hesitate to place my own on record as guideposts to those who may be seeking the most direct road to success in nut culture. Having had a rather extended and expensive experience in the cultivation of filberts, I propose giving a brief account of it here, with the hope that it may save some other enthusiast from losing time and money.

My attention was first specially drawn to these nuts in 1858,--while a resident of the city of Brooklyn, N. Y.,--by a neighbor who had a moderately large garden, on three sides of which he had planted a row of English filberts. These trees, at the time, had attained a hight of about fifteen feet, with broad, open heads, and they rarely failed to produce a heavy crop of nuts, which sold readily at very remunerative prices, for as they were always gathered in the husks and sold by the pound, the amount obtained from these few trees seemed to be enormous, considering the small space they occupied in this garden. The owner of these filbert trees, being an Englishman by birth, never tired of showing his English filberts to visitors, and of descanting upon their value, as well as upon the stupid indifference of the Yankees in neglecting the cultivation of these valuable nuts. I imbibed enough of my neighbor's enthusiasm to secure a good stock of his plants, a few years later, for cultivation in my grounds here. The third year after planting, quite a number of the bushes produced a fair crop of nuts, but I noticed that an occasional shoot was affected with blight, and these were immediately cut out and burned. The next season more of the branches were affected, and from these the blight extended downward on the main stems, and when these were cut away the sprouts from below made a very vigorous and apparently healthy growth, some reaching a hight of six feet the first season, but a year or two later these were also attacked and destroyed by blight.

Finding that the filberts in my grounds were doomed, I visited my old neighbor in Brooklyn, hoping to learn something of the origin or cause of the disease; but the blight had invaded his garden, and not a tree remained. On my return from this visit I had every filbert and hazel plant on my place dug up and burned, thinking by such means to stamp out the disease. After waiting ten years, I thought it time to try filberts again, and to be certain of securing pure and healthy plants, I concluded to raise them from the nuts, and sent an order for a few pounds of the largest and best variety to be found in the celebrated filbert orchards of Kent, Eng. In due time the nuts arrived, and they were very large, and all of one variety, as ordered. They were mixed with sand and buried in the garden until the following spring, then sown thinly in shallow drills and covered with about two inches of rich soil.

At the close of the first season the plants were from one to two feet high and quite stocky, with a mass of small fibrous roots. The next spring they were transplanted into nursery rows, and set about one foot apart. The third spring I laid out about one acre for a specimen filbert orchard, and after the ground had been thoroughly prepared, the plants were set ten feet apart in the row, and twelve between the rows. No crop was planted among the trees, but the ground was kept clean and free from weeds during the summer, with cultivator and harrow. All suckers springing from the base of the stems were removed as soon as they appeared, and under such treatment the plants made a vigorous growth. Two years later quite a number of the trees came into bearing, these showing that I was likely to have nearly as many varieties in my orchard as there were trees. Some of the varieties might be better than the parent, but the greater part were certain to be inferior in size. The fourth year after planting in the orchard the trees gave me a heavy crop of nuts, and they made a fine appearance as one looked down between the long rows, as shown in Fig. 40. But this season my old enemy, the filbert blight, appeared again, and branches and main stems began to blacken and the leaves to wither. But I had bushels of nuts and in great variety, and by sending specimen baskets of the long-husk varieties to dealers in New York, learned that there was an almost unlimited demand for such nuts, at prices ranging from thirty to seventy-five cents per pound, if sent to market in their fresh, half-ripened husk; but later on, when the nuts have fallen out and become thoroughly ripened, as when imported, ten cents a pound may be considered an average price for the larger varieties. Several of these are shown in Fig. 41, of natural size and form. Another extra-large hazel is shown in Fig. 42. The fifth year after planting, my specimen filbert orchard had suffered so much from blight that it appeared as shown in Fig. 43; but a few dozen trees have been reserved, the rest being removed and reduced to ashes.

=Name and Nature of the Filbert Blight.=--The reader must not suppose that one who has spent as much time and money as the writer in experimenting with these nuts, would make no effort to discover the origin and name of such a virulent disease, and means of destroying it if these were known. For many years I had been well aware of its presence in nearly all of the nurseries of the older States, as well as in the public parks and private gardens. In the meantime I had diligently examined the reports of the Division of Vegetable Pathology of the U. S. Department of Agriculture, as well as the hundreds of bulletins of the various State experiment stations, treating of the fungous diseases of plants, all without finding a hint or reference to this widely distributed and destructive blight of the filbert. I also sent many specimens of the diseased twigs and branches to professional mycologists, with no better results. With the nature of the disease, its mode of multiplication and distribution, I had become somewhat familiar, but the information sought was: Had it ever been described and given a scientific name, and if so, where, and by whom? This much of its history had somehow escaped me, and, as it would appear from the following correspondence, the chances were none too good of finding it.

In reply to an inquiry directed to the U. S. Department of Agriculture, Division of Vegetable Pathology, I received the following:

WASHINGTON, D. C., Aug. 4, 1894.

DEAR SIR:

Your letter of Aug. 2, relating to the disease of the filbert, is at hand. In reply I have to say that we have not investigated this trouble, and are therefore unable to furnish you with any definite information upon it. Specimens of the disease, as you describe it, have never been, so far as I know, referred to the Division, nor am I able to find any record of any such disease in foreign or domestic literature. If you will send us specimens we shall be pleased to examine them and furnish you a report. We should also be pleased to have any information from you in regard to the manner in which the disease works. Very truly,

B. T. GALLOWAY, _Chief of Division_.

The specimens requested were forwarded promptly by mail, and in the absence of the Chief of Division, they fell into the hands of one of his assistants, who reported as follows:

DEAR SIR:

Your letter of Aug. 7 is received, together with the specimens. The stems of the _Corylus_ are affected with one of the Pyrenomycetes. _Cryptospora anomala_, Pk. The fungus is described in "North American Pyrenomycetes," by Ellis and Everhart, p. 531. It attacks _Corylus Americana_, but appears to be worst on the European varieties, as you say. The pustules appear first on the young branches, and later on the older ones and on the trunk. The roots are not killed.

The only remedy known is to cut out and burn the diseased stems. Whether Bordeaux mixture or any other copper solution will protect the shrub from attack, is not known. So far as I know, it has not been tried. It is probable, however, that if the stems were thoroughly sprayed with the Bordeaux mixture they would be protected from attack. The mycelium of the fungus grows into the cambium and practically girdles the stems. The black pustules contain the spores.

Very truly yours,

ALBERT F. WOODS, _Acting Chief_.

On the receipt of this note of Prof. Woods, I looked up Ellis and Everhart's work, a voluminous one of over 800 octavo pages, published by the authors at Newfield, N. J. This filbert blight is briefly described under the scientific name of _Cryptospora anomala_, Pk., but Prof. Peck writes me that "the description was made from specimens discovered near Albany, N. Y., in May, 1874. In 1882 this description was republished by Saccardo, in his "Syllage Fungorum," Vol. I, p. 470, under the name of _Cryptosporella anomala_. The original name in Report 28, p. 72, was _Diatrype anomala_. In 1892 Ellis and Everhart, in "Pyrenomycetes of North America," p. 531, changed the name again, making it _Cryptospora anomala_." So at present we have the names of this fungus in the following order:

_Diatrypes anomal_, Peck, 1876. _Cryptosporella anomala_, Sacc., 1882. _Cryptospora anomala_, E. and E., 1892.

Ellis and Everhart, after giving scientific description, add,

"On living stems of _Corylus Americana_, Albany, N. Y. (Peck), Iowa (Holoway), on _Corylus Avellana_, Newfield, N. J. The pustules appear first on the smaller branches, and are serrately arranged along one side of the branch; afterwards they appear also on the larger branches and on the trunk itself, and in the course of two or three years the part of tree above ground is entirely killed. The roots, however, still retain their vitality, and continue to send up each year a luxuriant growth of new shoots, destined to be destroyed the succeeding year by the inexorable pest. The imported trees seem to be more injuriously affected than the native species."

The observations of Ellis and Everhart and Prof. Woods accord with my own, but I may say that the infested branches often show the presence of the mycelium in the bark and alburnum,--by a slight shrinking,--weeks or months before the pustules appear, for these are merely indications of the last stage in the life of the fungus, and with the throwing off the spores from these pustules the old parasite perishes.

The pustules, when fully open, are from one-sixteenth to one-eighth of an inch in diameter, usually round, but sometimes slightly oval in form, and placed mainly in almost straight rows lengthways of the branch, as shown in Fig. 44. These pustules appear on wood of all ages, from two years upward, and in what may be termed patches, ranging from a few inches to a foot or more in length, and more frequently on the upper side than the underside of the branches.

This fungus is undoubtedly indigenous, and its host plant is the common American hazel (_C. Americana_). From a very careful search, I have not been able to find any clump of these bushes of any considerable size that was entirely free from pustulous stems. But on these wild plants it seems to do but little harm, for if a stem is killed, another soon springs up from the roots to take its place; but when this fungus invades our orchards and gardens and attacks filbert trees, we recognize it as an implacable enemy. How far the spores of this fungus are likely to be carried by the wind, transported on the clothes of a person, or the hair of domestic animals, I do not know, but it certainly is not safe to plant the susceptible species and varieties within a mile of the wild hazel bushes, unless the planter is prepared to use fungicides freely on his trees. There are certain phases of this filbert blight that are rather obscure and scarcely explainable; as, for instance, its virulence among some species and varieties, and almost if not total absence among others. So far as my observation extends, I have never found it attacking the native beaked hazel (_Corylus rostrata_), and my correspondents in the Northwest and in the Pacific States assure me that no blight on the hazel has, as yet, been found there, and its absence is probably due to the fact that the common hazel (_C. Americana_) is not an inhabitant of these regions.

In a neighbor's garden just across the highway from my own, there are, at this time, four old European hazelnut trees, fully twenty feet high and as many years old. They are of two varieties: one a small round nut, the other a long, slender nut, but neither of much value, because of their small size. The trees, however, are perfectly healthy, never having suffered from the blight, although these four are all that remain of a long row of choice European varieties all planted at the same time. Blight destroyed the better varieties, while these inferior ones continue to thrive and are exceedingly productive.

This native fungus that causes blight in the hazels is but one of a large number of similar maladies which have appeared and often worsted the horticulturist, in his endeavor to introduce and cultivate foreign species and varieties of plants, and like the tropical fevers, they may pass unnoticed among the natives, but are terribly fatal to immigrants from cooler climates. The disease so well known as the black knot (_Otthia morbosa_, Schu.), and widely destructive to the European varieties of the plum, and Morello cherries, has existed for ages among our native plums and black cherries, doing comparatively little harm; but it seems to protest, by its virulence, against the introduction of some foreign species. The same is true with various blights and rusts which attack the exotic pear, apple, quince, peach, and other of the larger fruits, and we have only to ascend the scale a few degrees from the microscopic fungi to the microscopic insects, to meet on the very threshold of this realm the minute but unconquerable grape louse (_Phylloxera vastatrix_), which for more than two centuries has prevented the successful cultivation of the European varieties of the grape in the open air everywhere east of the Rocky mountains in North America; although this minute insect has ever been present and a constant parasite of the indigenous species of the grape, but scarcely affecting the health of its host. The plum curculio, chestnut and hickory weevils, bean weevil, and many other similar species of insects appear to be ever protesting against the introduction of exotic plants, as well as the improvement of our indigenous kinds.

It is this blight, and nothing else, that has prevented the extensive cultivation of the improved varieties of the European filbert and hazelnut in this country, and not the uncongenial soil and climate, as has been so often "officially" proclaimed by men whose theories are far greater than their practical knowledge of such subjects. Men whose experience with these nuts has been limited to a few isolated bushes or trees in gardens or nurseries, where they were protected, or beyond the reach of the spores of the blight fungus, as has already been noted in the experience of Prince, Downing, Barry, and my neighbor Butler, of Brooklyn, could scarcely understand why others should remain so indifferent to such a promising industry, or why the demand for the trees remained so limited, with scarcely an attempt to plant filbert orchards anywhere in this country. Nurserymen have continued to offer the choice varieties at low prices per plant, and to advise their customers to cultivate filberts extensively, even to setting them in hedgerows; and yet home-grown filberts remain as rare in our markets as they were a hundred years ago, and all due to the simple reason that the insidious filbert blight still scatters its spores unrestrained.

With the present almost universal employment of various fungicides for the destruction of blights, mildews and rusts on cultivated fruits and vegetables, we may confidently assert that the diseases of the filbert may be readily controlled by the same means. The spraying of the trees with Bordeaux mixture and other copper solutions will certainly destroy the fungus spores, and with these out of the way filbert culture may become of as much importance and as popular here as it is in certain countries of Europe. In my own experience I have found no other nut tree (barring always the blight) that has been more satisfactory. The plants come forward rapidly, fruiting freely and abundantly when young, and if properly trained, the crop can be gathered with little labor, and as it is ready for use a month or more in advance of the arrival of fresh nuts from abroad, the home market during the time is at our command.

The number of applications of the fungicides that will be necessary during the season to rid the trees of blight, or the strength of the copper solution used, will depend somewhat upon circumstances and the condition of the subjects operated upon. If the trees are growing near hedges of wild hazels, where there is a constant or annual influx of the fungus spores, then greater care will be required to suppress them than if the trees are some distance from such sources of contagion; and it may be well for those contemplating planting filbert orchards, to examine their surroundings carefully in advance, in order to avoid local blight-breeding plants, and have these destroyed if any are found. I would also warn the cultivator against collecting branches of the wild hazel in the spring, carrying pollen-bearing catkins to be employed in fertilizing the pistillate flowers of the cultivated varieties, for by such means blight spores may be readily introduced into orchard and garden.

It will seldom be necessary to practice artificial fertilization, where any considerable number of trees are grown near together, because if ninety per cent. of the male catkins are winterkilled, the few remaining will be sufficient to supply pollen for the pistillate flowers. In my grounds filberts have never failed to produce annual crops after reaching a bearing age, although they have been subjected to great extremes of temperature in winter. One year the trees were in full bloom the last week in February, and although cold weather followed, the protected pistillate flowers were not injured. The winters of 1894 and 1895 were among the severest, in the way of continuous low temperature, I have ever experienced here, and while the filberts did not bloom until the first week in April, the crop proved to be abundant.

=Insects Injurious to Filberts.=--My personal observations lead me to believe that the filberts and hazels are, in this country, remarkably free from the depredations of noxious insects. Two species of nut weevils have been reported as breeding in the wild hazelnuts, viz., _Balaninus obtusus_, and _B. nasicus_, but among the many bushels of the European varieties of the filbert produced in my grounds I have never found one infested by a weevil or other insect. In Europe a nut weevil (_B. nucum_) is said to be very destructive to the wild hazel, often invading the filbert orchards, and this we can readily believe, because they are not at all uncommon in the imported nuts, but fortunately have not, as yet, become naturalized in this country.

The great hazel-leaf beetle, or as more generally known, elm-leaf beetle (_Monocesta coryli_), has been known in a few instances to attack and defoliate large patches of the wild hazel bushes, but this insect seems to prefer the elm, hence is rarely found on the hazels. But should it ever invade our filbert orchards, it can be readily destroyed by dusting or spraying the trees with Paris green, London purple, or other well-known insecticides. There may be an occasional invasion of caterpillars, like the tent worms, spanworms, leaf rollers of various species, and what are called leaf miners, but as these infest almost all kinds of deciduous trees and shrubs, we cannot consider them specially injurious to the filberts and hazels.