Forestry in New England; a handbook of eastern forest management

Front matter

NEW ENjii'

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Preface

Throughout America and especially New England there has been a rapid awakening of interest in forestry during the past few years. The disappearance of old forests, together with increased prices of lumber, has made ready converts to the forestry propaganda of the federal and state governments; but up to the present time nearly the only available literature on the subject is in the form of government bulletins. There are, to be sure, a number of good books on the trees written from a botanical standpoint, and several books dealing with forestry in a general way, besides a very few advanced textbooks. There is now such widespread interest in the subject, that a book dealing with the specific forestry problems of New England will not only be of interest to the nature lover but of real assistance to the land owner who wishes to adopt approved methods of forest culture, or to the student of forestry. Books are legend dealing with specific agricultural problems, and it is intended that this work shall be for the woodland owner what these are for the agriculturist. Every year more people are moving from the cities and acquiring country places. Many owners of this class cannot afford their personal time for farm supervision, and, without this supervision of the owner, farming is apt to be too expensive. Forestry particularly appeals to this class of owners because it requires less frequent attention than any other land culture.

It is gratifying to find that the farmers themselves are taking up forestry in the same practical way in which they are accustomed to handle other problems, and the authors frequently have been asked by farmers to recommend some good book on forestry. Practical problems, such as the planting of an old hill pasture to pine, or the advisability of pruning pine and

Vi PREFACE

spruce; the proper treatment of a sugar orchard, — these and many similar questions are constantly being asked by the upto-date farmer.

Lumbermen also are becoming interested in forestry, .and, while they have not yet to any extent adopted modern methods of cutting, this is largely due to unfavorable conditions and ignorance of such methods.

In preparing this book the authors have been governed by a twofold purpose: first, by the desire to present a book which might be of practical assistance to all classes of land owners in the East; and second, to produce a textbook treating of forestry in New England. The latter is greatly needed, especially in the various agricultural colleges where courses in forestry are given, and where it is essential that thorough instruction in the forest problems of the northeastern United States be furnished. There is even a wider field for a book dealing with a definite section of the country, so arranged as to serve as a handbook for owners of woodland in the section treated. It has been the aim of the authors thoroughout to present the material in the simplest and least technical form possible, with the view of making everything clear to persons not familiar with forestry.

The book is arranged in two parts : one dealing with methods and principles of forestry in general, the second treating in detail with the forests of New England. While it is written with special reference to New England, the book has a much wider field of direct application. Forest conditions similar to those in portions of New England prevail over a large part of New York and New Jersey, in Pennsylvania, and also in southeastern Canada.

Part I is intended to furnish the woodland owner with a brief survey of the whole field of forestry, and to give him sufficient knowledge to rightly understand and be able to carry out the treatment recommended in Part II for his forest land. The subjects in Part I are too comprehensive to be fully covered in one volume. In many cases the presentation here will be

PREFACE Vii

sufficient, but if a complete discussion is needed various more technical works restricted to a single subject should be consulted. For example, two books by Graves, " Forest Mensuration " and " Principles of Handling Woodlands," cover mainly the three subjects " Silvicultural Systems," " Timber Estimating " and " The Growth of Trees and Forests," which are here included in three chapters.

As a textbook, then, for the post-graduate forest schools giving the highest grade of instruction, this book will have a greater value for its detailed discussion of New England forests, than for the portion dealing with general forestry. But it is hoped that, for numerous undergraduate forest schools giving a slightly lower grade of instruction, all portions of the book will prove useful.

The publications of the United States Forest Service relating to New England topics, as well as those issued by the Forestry Departments of the different New England States, have been freely consulted, and much of the information which they contain has been incorporated in these pages.

Free use has also been made of various books dealing with the subjects treated in these chapters. Among them are the following: " EQstory of the Lumber Industry in America" by Defebaugh; "Studies in Forestry" by Nisbet; "Principles of Handling Woodlands" and "Forest Mensuration" by Graves; "A Textbook of Botany" by Strasburger Schenck, Noli and Schimper; " Handbook of Trees of the Northern States and Canada" by Hough; and various articles in Forestry Quarterly too numerous to mention.

All the tables in the appendix, with the exception of certain log rules and several tables taken from a " Manual for Northern Woodsmen " by Prof. Austin Gary, have been secured from state or federal forest service publications. In connection with each table acknowledgment is made of the source from which it was obtained.

The sketches and a majority of the pictures are original with the authors, although a large number were secured from other

VUl PREFACE

sources. Wherever a picture was not taken by the authors its origin is stated beneath the picture.

In conclusion, the authors wish to render acknowledgment to the many friends who have assisted with helpful suggestions in the preparation of this book.

Chapter II. Silvicultural Systems 17

I. Systems depending on Reproduction by Seed 17

Selection System ' 17

Clear Cutting Systems 20

Clear Cutting with Artificial Reproduction 21

Clear Cutting with Natural Reproduction 22

Clear Cutting the Whole Stand 22

Reserving Blocks of Trees 22

Reserving Scattered Seed Trees 24

Reserving Thrifty Standards 25

Clear Cutting in Strips 26

Clear Cutting in Patches 27

The Shelterwood System 27

n. Systems depending on Reproduction Wholly or Partly from

Simple Coppice 32

Coppice with Standards 33

Pole-wood Coppice 35

Chapter III. Silvicultural Characteristics of the Important New England Trees 37

Wb'te Pine 37

Red Pine 41

Pitch Pine 42

Scotch Pine 43

Red Spruce 45

Norway Spruce 47

ix

CONTENTS

PAGE

Balsam or Fir 48

Hemlock ^g

Tamarack 50

European Larch ^ i

Arborvitae.

Juniper 52

Sugar Maple 53

Soft Maple 54

Yellow Birch ,

Paper Birch ^^

Gray Birch e6

Beech

White Ash 58

Basswood 58

Poplar 59

Chestnut 60

White and Red Oaks 62

Tulip Tree 63

Chapter VII. Forest Insects and Fungi loi Insects loi

White Pine Weevil loi

Pine Bark Aphid 103

Spruce Destroying Beetle 105

Spruce Budworm 106

Gipsy Moth 108

Brown-tail Moth no

Larch Sawfly m

Elm Leaf Beetle .

Forest Tent Caterpillar 114

June Bug 116

Fungi 118

Chestnut Bark Disease 118

Trametes pini 122

CONTENTS XI

PAGE

Polyporus schweinitzii 123

White Pine Blister Rust 124

White Heart Rot 126

White Pine BHght 129

Chapter XIII. The Spruce Region 2cx) Spruce Flat 206

Spruce Slope 209

Xll CONTENTS

PAGE

Birch and Poplar 2 1 r

Spruce Slope 217

Spruce Flat 220

Old Field Spruce 226

Planting 231

Avoiding Waste in the Woods 232

Logging Methods 235

Market Conditions 242

Pulpwood 243

Lumber Industry . . 245

Special Woodworking Industries 248

Summer Resort Business 249

Character of the Land and Timber Ownership 251

Forest Fires .

253 254

Methods of Fire Protection 257

Fighting Fires 261

Protection against Grazing Animals 262

Protection against Insects 262

Protection against Fungi 263

Watershed Protection 263

Chapter XIV. The Northern Hardwoods Region 265 Old Field Hardwoods 273

Old Field Conifers 274

Old Field Hardwoods 284

Old Field Conifers 285

Logging Methods 285

Market Conditions 287

CONTENTS Xlll

PAGE

Lumber Industry 288

Maple Sugar Industry 289

Character of the Land and Timber Ownership 290

Methods of Fire Protection 292

Protection against Grazing Animals 293

Protection against Insects and Fungi 295

Watershed Protection 295

Chapter XV. The White Pine Region 296 Pitch Pine 30i

White Cedar Swamp 301

Pure White Pine 303

Pine and Inferior Hardwoods 3°^

Soft Maple Swamp 312

Waste Land 312

Hemlock 3 H

White Cedar Swamp 3^6

Pitch Pine 316

Pure White Pine 318

Pine and Inferior Hardwoods 323

Soft Maple Swamp 325

Waste Land 325

Logging Methods 327

Market Conditions 328

Ownership of Woodlands 332

Methods of Fire Protection 335

Methods of Fighting Fires 339

Protection against Grazing Animals 339

Protection against Insects and Fungi 34°

Watershed Protection 34i

Summary 34i

Chapter XVI. The Sprout Hardwoods Region 342 CONTENTS

PAGE

Hardwood Swamp 350

Cedar Swamp 351

White Pine 351

Hardwood Swamp 360

Cedar Swamp and White Pine 36 1

Logging Methods 362

Market Conditions 364

Ownership of Woodlands 366

Methods of Fire Frotection 369

Methods of Fighting Pires 371

Protection against Grazing Animals 371

Protection against Insects and Fungi 372

Watershed Protection 372

Chapter XVII. The Progress of Forestry in New England . . . 374 Forest Administration 379

Connecticut , 379

Forest Taxation 386

Control of Gipsy and Brown-tail Moths 388

Rhode Island 389

CONTENTS XV

PAGE

State Forests 39i

Control of the Gipsy and Brown-tail Moths 391

Vermont 39^

Maine 399

Insects 403

Forestry Practice 403

Lands under State Ownership 403

Lands under Corporate and Private Ownership 404

Chapter XVIII. The Yield to be Expected from New England Forests under Proper Management 408

Appendix 417

Forest Fire Statistics 417

Log Rules 427

Volume Tables 438

Growth of Individual Trees 464

Yield Tables 466

Index 475

PART I.

GENERAL FORESTRY.

Chapter I. Silvics

In any study of forests over a wide range of country, as a whole continent, it must be apparent that climate determines the character of the forest just as it affects the growth of agricultural crops in certain regions or belts. In a small region, such as New England, the climatic factors are less noticeable, but cannot be overlooked.

The average temperature of a region is of less importance in determining the range of different trees than the lowest and highest extremes of temperature. In these extremes we have an explanation of the inability of the eucalyptus of southern Cahfornia to live in New England, and of the fact that the canoe birch, although growing from the Atlantic to the Pacific, does not extend as far south as Long Island Sound. In a less noticeable way it is probably the extreme cold of winter which limits the chestnut to southern New England and the region farther south. Aside from this matter of extremes it is not so much the winter's cold that is injurious to species, as the late frosts in spring when the young leaves and shoots are still tender, and the early frosts of the autumn before the summer's growth has sufficiently hardened to withstand the cold. The late frosts of the spring of 1910 killed back the new growth of pine and fir in northern Vermont.

Besides temperature there are other chmatic factors influencing tree growth. It has been found, for example, that the southern limits of forest trees are mainly determined by the quantity and the regularity of the rainfall during summer. Taken as a whole, broadleaf trees consume on the average about ten times as much water as conifers, and, owing to the light foliage of pine, this species requires much less soil moisture than spruce or fir. The lack of rain for even two or three days may be fatal to young seedlings. White pine plantations established two years previously were badly killed out by the prolonged drought and hot weather of 191 1. With age and development of the root system the ability of the tree to resist drought increases. A mature tree with the assistance of its reserve supplies of water can withstand a drought of several months' duration. Precipitation outside of the growing season is also valuable, in thoroughly wetting the soil, because during the growing season when the trees are in foliage the soil is seldom thoroughly wet.

Aside from these climatic factors, heat and rainfall, which influence the general distribution of forests, the factors most important to individual tree growth are light and soil moisture, and to a lesser extent the physical and chemical character of the soil. Each genus, and in some respects each species, reaches its best development under a certain set of conditions of soil, climate, etc., called its optimum, and varies whenever found under different conditions. Since topography, exposure, and altitude affect these factors, they must also be taken into account. Near their northern limits of distribution all trees ascend the mountains to a greater height on the southern than on the northern sides, because of warmth requirements.

Trees derive most of their nourishment from the carbonic acid of the atmosphere, but they depend upon the soil for water and mineral supplies; these can only be taken up when held in solution by the soil. Water is a chief essential of tree growth, part of it being retained in the wood. Greenwood often contains as much as 50 per cent by weight of water. Water in the plant serves as a carrier for the minerals (the salts, oxides, etc.), which, being non-volatile, remain in the plant after the water is given off. The process of taking up minerals in solution through the roots, of depositing these minerals, and of giving off water from the leaves is called transpiration; this is one of the leading features of plant life. Trees of normal size lose by this process from lo to 25 gallons of water daily, and it has been estimated that a large oak with 700,000 leaves gives off 244,000 pounds of water in the five months from June to November, or an average of 25 tons a month — nearly one ton a day. Transpiration is greater in the daytime than in the night, and leaves exposed to the sun transpire from three to ten times as much water as those that are shaded. There has not yet been developed any very satisfactory theory explaining the movement of water to the top of a high tree. It is known that the minute root hairs at the ends of the roots fasten themselves to the soil particles and withdraw water from them even when they appear dry; and it is probable that the transpiration current, which flows through the wood to the leaves, is forced up by a combination of atmospheric and root pressure aided by osmotic force ^ and capillarity. As has been said, the conifers are more moderate in their demands on water than the broad-leaved genera. This is the reason why sand plains, such as those of Cape Cod, can support the pine. The water table is always found to be farther removed from the surface of the ground under forest than outside it or under a cut-over forest; under old forests it is lower than under young stands. Seedhngs spring up in a forest when the roots of the adjoining trees are cut through, thus allowing the water table to come nearer the surface. From the illustration of the oak mentioned above it will be readily realized, in dry seasons especially, that the amount of water available per tree might well be the controlling factor influencing growth or life itself. Forests transpire more moisture than other vegetation under the same conditions. Any deficit caused by excess of transpiration over precipitation is necessarily made up by water from the

1 See "A Text Book of Botany," Part I, Sect. II, by Strasburger, Schenck, Noll, and Schimper.

open. Other things being equal and leaving the surface out of account, the soil under a mature forest is drier than in the open. Thus seedlings grown in the open get more moisture in a dry season than under large trees, but. on the other hand, the intense heat in the open may more than counterbalance the greater supply of water.

The chief element of dry wood is carbon, which forms about one-half the dry weight of plants. This element is entirely absorbed from the carbon dioxide of the atmosphere through the process called assimilation. As there are only two grams of carbon in 10,000 Hters of air, one tree with a dry weight of 5000 kilograms requires about 1 2 million cubic yards of air to furnish the carbon. But for the fact that the air is being constantly resupplied with carbon exhaled by animals and poured forth from factories and chimneys these figures would seem startling. The process of assimilation, or the taking of carbon from the carbon dioxide, can only be carried on by the chlorophyll or green bodies in the leaves, by the action of sunlight, and a definite amount of heat. The first products of assimilation are carbohydrates, either in solution or as starch grains. The process ceases at night and the starch grains are dissolved and pass out of the cell. The surplus products that are not needed at once are stored. This surplus is greatest at the end of the growing season, and upon its amount depends all growth of the next year either of mother-plant or offspring in germinating seed. This material is stored in the form of starch or sugars in the embryo of the seed, in tubers, bulbs, roots, and medullary rays of the wood.

All trees require a certain amount of light in order to carry out this work of assimilation. With regard to their ability to bear shade, marked differences occur among the various species of trees, so that they may be classed as: light-demanding or intolerant trees, such as larch, red cedar, and gray birch; and shade-enduring or tolerant species, such as beech, spruce, hemlock. Between these is a class of intermediate trees, including white pine and chestnut. The demands of various species for light may be gauged by the general density of the foliage of the crown and the capacity of overshadowed twigs to retain life.

Until very recently it was thought by foresters that the amount of light to which a tree has access determines its growth more than any other factor. Recent investigations of soil moisture indicate that this is an even more important factor, so that while it was customary formerly to attribute increased growth, after thinning a forest, to more light, it now appears that it is due as much to the increased supply of water available for the roots.

The physical qualities of soil especially as related to ability to retain moisture, are more important than the chemical constitutents, for almost all soils are chemically able to bear trees. The root systems of various species vary greatly with regard to shape and the depth to which they reach; but even shallowrooting kinds derive advantage when the soil over which they grow is deep, owing to the greater fertility within easy reach of their roots. Some species, like the oak, have a strong tap root; others, such as beech and birch, develop strong side roots, but no tap root; and still others, like spruce, have a pronounced shallow-root system. Spruce and birch require least depth of soil, oak most. Whether the soil is loose or binding is a matter of great importance for tree growth. As a rule, the broadleaf trees do better than the conifers on the stiff er classes of land, although soils of average tenacity are on the whole most suitable for all kinds of trees. The chief constituents of soil are clay, lime, and sand; and as clay yields the most valuable materials for plants, the qualities of soil are often determinable to some extent by the quantity of clay in them. Clay soils are hard and interfere with the movement of moisture; sands are too porous; limes too easily heated; loamy soil, therefore, is usually best.

The chief chemical constituents of wood are carbon, hydrogen, oxygen, and nitrogen, but the ashes of wood also contain sulphur, phosphorus, chlorine, silicon, potassium, sodium, calcium, magnesium, and iron. The carbon is obtained solely from the carbonic acid of the air; the hydrogen and oxygen are derived chiefly from the water in the soil; and the nitrogen from the ammonia of the soil formed by nitrifying bacteria from organic decaying matter. These other chemicals taken from the soil in salts and oxides are contained in very small quantities. Thus iron, though very important for the formation of chlorophyll in the leaves, is present only in very small quantities, so the old remedy of driving nails into a dying tree was of no value.

The percentage of pure ash in the dry leaves of trees varies from 2.3 per cent in white pine to 7.6 per cent in the ash tree, and dry leaves have a higher percentage of minerals than wood. This indicates the well-known fact that conifers are less demanding as regards chemicals than broadleafs. For this reason the soil improves under coniferous crops if a good canopy is maintained, as the minerals accumulate. It also illustrates the way in which a forest soil is annually renewed by the return of the leaves rich in minerals.

Of all the elements taken from the soil nitrogen is the most important. The chief source of nitrogen is the raw humus composed of decayed leaves and wood. It has been found that dead leaves mixed with soil absorb nitrogen from the atmosphere in large quantities, probably through the assistance of bacteria, mosses, and lichens. This capacity of the bacteria is reduced by frost, so the supply of nitrogen is less in the open in places exposed to frost. Some plants take in nitrogen from the air through their leaves. About 10 pounds of nitrogen are carried to the ground per acre annually by rain, and the litter of leaves and twigs carries to the ground in a beech forest 40 pounds, in spruce 28 pounds, and in pine 26 pounds of nitrogen per acre. On the other hand, the annual consumption of nitrogen for wood production is 9 pounds for beech per acre; 12 pounds for spruce and fir; and 6| pounds for birch. An investigation in a plantation of maritime pine on a sand dune 56 years after planting produced, from a layer of soil 6 inches deep, 7 tons of organic matter per acre with nitrogen 1.5 per cent, or 248 pounds of nitrogen per acre. This is an annual accumulation of 4.5 pounds per acre. In another plantation the average accumulation was 7.2 pounds per year.^

As regards the chemical composition of soil, sour, marshy soils are unsuited to most species except Scotch and white pine and spruce. These are about the only species that will thrive on pure peat. Ash, maple, beech, and elm require a moderate amount of lime in the soil, and oak, locust, European larch, and Austrian pine thrive best on soils which contain some lime, while chestnut seems to do better in a soil containing very little lime. Some recent investigations in soil seem to show the commanding importance of lime as a controlling factor in tree growth. Most trees are lime-loving to a certain extent, but an overabundance of lime in all cases is unfavorable. The hardwoods — oak, ash, maple, chestnut, beech — seem to demand the presence of a considerable quantity of potash; spruce, fir, pine, and birch thrive on soils rich neither in lime nor potash. For the production of wood only, the demands vary as follows in high forests: from 4 to 20 pounds of lime; from 2 to 10 pounds of potash, and from ^ to 4I pounds of phosphoric acid per acre per year. The combined influence of all these factors dependent on soil and situation is shown in the amount of timber produced per acre and in the quality of the timber.

When the trees of a wood are tall and straight, free from branches, and tapering but little, it is the best possible indication that the soil and situation are eminently suited to the woodland crops growing on them.

These factors of climate, soil, etc., have influenced the distribution of trees in such a way as to form forest "types." In crossing a mountain ridge we find one type of forest in the swamp at its base, which is quite distinct in its composition and appearance from that on the drier, rolling land just beyond. On the steeper slopes another forest type is substituted, just as the human type raised in the wild mountains differs from that of the fertile valleys below. Scientific forestry largely deals with the causes for: these varied types, while applied

^ See Forestry Quarterly, Vol. VI, p. 290, and Vol. VII, p. 192.

forestry, based on this knowledge, tries to develop in every locality the type which is best fitted to exist there.

The term "stand" is the unit of description applied to any definite portion of a forest having a definite distinguishing characteristic. Thus in a certain type we may have a stand of young growth; a stand of diseased and damaged trees; a stand of exceptionally tall specimens, etc. These stands may be extensive, covering many acres or they may be confined each to a small part of an acre.

Fig. I. — Two stands uf white pine of dififerent age classes. The one at the right is 40 years, that on the left 70 years of age.

Forest Types.

In every forest the ceaseless struggle going on gradually brings about many changes unseen by the casual observer. In the small openings of the forest, caused by windfall, snow breakage, or other causes, seeds of trees germinate and begin to grow. The kind of trees that come up here depends, as has already been shown, on many factors — the kinds of seed trees near, the covering of the soil and moisture content, the light available, etc. On the burned-over and freely-exposed mineral soils, poplar, bird cherry, and birch spring up freely; on the abandoned fields, pine and spruce are especially apt to appear; and on the moss-covered decaying logs of the northern woods, little hemlocks, fir, and spruce seedlings start. In a few years the growth and very existence of these seedlings are influenced and other changes take place. The tops of the old trees may spread out and shade the openings, so that only the tolerant seedlings can endure; or the remaining old stand may be felled and an unlimited amount of light admitted. Under this impetus certain rapid-growing species may push up to the entire exclusion of the others, or these others if they are tolerant of shade may be relegated to an understory of secondary importance. On an acre of forest soil thousands of such seedlings may start, but in the course of their various struggles and under innumerable external influences their ranks are so thinned that only a few hundred grow into fair-sized trees. A stand of looo trees per acre 20 feet high by the time it- is 80 feet high and correspondingly large will seldom contain over 400 trees to the acre. The trees that are killed in this constant strife fall to the ground after a few years, decay, and add to the humus of the soil. As the forest grows old gaps are caused by these deaths and reproduction again takes place. Whether the same kind of trees will come in depends upon the conditions at that time.

In every region certain combinations of forest trees and underbrush are characteristic of different sites. As already explained, this community of tree life is called a ''type," and is influenced by soil, exposure, elevation, moisture, and other factors. As examples of types, we may mention the ''spruce slope type," characteristic of the steep mountain slopes of northern New England, and "chestnut oak type," of the trap ridges of Connecticut. Under natural conditions such a forest type maintains itself century after century on the site to which it has become adapted. Accordingly it is known as the permanent type of that particular site. Circumstances not in the regular course of nature may entirely change the conditions and cause the lO FORESTRY IN NEW ENGLAND

appearance of a different forest type. Such influences are windfall, extensive damage by heavy snows, by insects or fungi, by fires, and by lumbering or clearing for farming. The type following any change of this sort is a temporary type, as, for example, the "poplar type" on burns, or the "old-field type" on abandoned cleared lands. Gradually this temporary type, if left to itself, will change into the permanent type and after perhaps fifty or one hundred years the forest will have the form and composition that it had before the change. Such is nature's way of asserting her rights.

Every forest type will be found under a considerable variety of condition of soil, moisture, etc., and, of course, will make its best development where the sum total of conditions is most favorable. Foresters recognize this situation as Quality I for the type, and usually speak of Qualities II and III as designating respectively poorer sites.

Pure and Mixed Stands.

One of the first things to notice in the study of a forest is the kind of trees that are present and the proportion of the more important ones. In the virgin forests of northern New England, for example, we find spruce, hemlock, birch, maple, beech, probably basswood, and several other species. The hardwood forests of Connecticut and Rhode Island, on the other hand, consist of chestnut, oak, hickory, maple, birch, elm, hornbeam, etc. Both of these are termed "mixed forests." But in the former region, especially in Maine, there are extensive areas that have been burned over which are now covered with canoe birch. There are old pastures in northern Vermont now overgrown with impenetrable thickets of arborvitae; and further south, with white pine. These are "pure forests," being composed of but one species. As used in this country a stand is called "pure" if 80 per cent of the main crop is composed of one species.