paris Scaghes Senco ne UNIVERSITY LIBRARY au ie 3 1924 086 576 92 Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924086576927 The Rural Manuals Epirep sy L. H. BAILEY MANUAL OF TREE DISEASES The Rural Manuals Epitep spy L. H. BAILEY ° & Manuva or Garpenine — Bailey Manvat or Farm Animas — Harper Farm anp GarpEn Ruie-Boox — Bailey Manvat or Fruit Insects — Slingerland and Crosby Manuat or WEEDS — Georgia , Tue Pruninc-ManvuaL — Bailey Manvat or Fruit Diszases — Hesler and Whetzel Manuva or Mitx Propucts — Stocking Manvau oF VEGETABLE-GARDEN InsEcts — Crosby and Leonard Manvuat or Tree Diszases — Rankin Manvat or Homse-Maxtne —Van Rensselaer, Rose, and Canon MANUAL OF TREE DISEASES BY W. HOWARD RANKIN, A.B., Pa.D. ASSISTANT PROFESSOR OF PLANT PATHOLOGY NEW YORK STATE COLLEGE OF AGRICULTURE AT CORNELL UNIVERSITY New Work THE MACMILLAN COMPANY 1918 All rights reserved CoryrieaT, 1918, By THE MACMILLAN COMPANY. Set up and electrotyped. Published Ni ovember, 1918. Norwood Press J. 8. Cushing Co. — Berwick & Smith Co. Norwood, Mass., U.S.A. PREFACE THE steadily accumulating knowledge of the diseases of trees in the United States has never been brought together and made available to the general public. The intention of this Manual is to describe and suggest means of control for the tree diseases that have been most studied. Much remains to be learned about many of these diseases, and still many more have never been investigated. Therefore, in the treatment of this subject there are many unavoidable limitations which the trained reader will perceive. The diseases of fruit-trees, and of field and vegetable crops, have received the attention of plant pathologists in most parts of the country for many years. The results of these investigations have been made available to the growers of these crops in various ways. On the other hand, the diseases of forest; shade, and ornamental trees have been largely neglected until very recently. Tree diseases cause enormous losses in the large tracts of forests on which we depend for timber. The timber owner has been slow to adopt the. fundamentals of scientific forest practice, and so far methods for the control of forest-tree diseases have not begun to operate in reducing losses. The owners of shade and ornamental trees are constantly con- fronted with diseases which they wish to control. They have become accustomed to controlling insects, but the funda- mentals involved in the appearance of a disease and the meas- ures necessary to protect trees from further damage are largely puzzling to them. An understanding of the cause of disease is essential to the undertaking of adequate control measures. That the tree is Vv vi PREFACE a living organism which requires water, food, air and sunlight is often overlooked. Many of the diseases outside the forest are due to the failure to recognize the importance of main- taining suitable conditions for tree growth. The soil must contain the proper supply of food materials, and be of a texture which will conserve the water and air that are necessary for healthy root development. Pavements and sod are frequently never considered as the cause of the decline and death of trees. Likewise, it is seldom appreciated that the smoke and poisonous gases in the atmosphere in cities kill many trees. Also the appearance of leaf-spots, cankers, wood-rots and root-rots in no way explain themselves unless it is understood that in- visible parasitic plants are growing in the living tissues of the tree and causing their death. The technical facts regarding the relation between a tree and its environment are more easily comprehended than the life history of the parasites which cause diseases. Nevertheless, the tree owner must understand the nature of these organisms, the appearance of the symptoms they produce, and many other facts regarding diseases before he can intelligently attempt their control. It is hoped that the details concerning the diseases discussed in this book will assist to that end. The treatment has been made as simple as possible, and only the essentials regarding the disease, which are necessary to recognize and understand it, have been in- cluded. A glossary is appended, which will assist in explain- ing the more technical terms. It has been necessary to treat the general and specific diseases separately. Those diseases which are more or less common to all kinds of trees are discussed in the first four chapters. The more specific diseases will be found in the chapters follow- ing, which are arranged alphabetically according to the com- mon name of the various groups of trees. Cross-reference has been freely made in the different chapters to more complete discussions found elsewhere. This would be unnecessary if PREFACE vii the book were to be read from cover to cover. The plan of the book is intended, however, to facilitate the diagnosis of a dis- ease of a certain kind of tree and to group the diseases of this tree in one place where comparisons may be made. Under each of the host-chapters, the diseases are arranged according to the part of the tree affected and will be found in the fol- lowing order: leaf, twig, branch, trunk and root diseases. The reader is advised to make free use of the index, which will facilitate the finding of those discussions unavoidably scattered. It is regretted that specific information is not yet available on many common tree diseases. Most of the leaf-spot diseases have not been studied. Likewise, control measures are largely limited to eradication methods, so far as definite reeommenda- tions can be made. This apparently will always be the case for the diseases of the woody parts of trees, until means of naturally or artificially immunizing trees are devised. Spray- ing and dusting for leaf diseases will be practicable when these diseases are better understood. Such methods are expensive, however, and their use will be limited for this reason. The author is indebted to Dr. F. D. Kern, who has read the discussions of the rust diseases and offered many helpful suggestions. Grateful acknowledgment is also made to Mrs. W. H. Rankin and to the following co-workers in the Department of Plant Pathology at Cornell University for many suggestions regarding the manuscript and for photographs loaned: Prof. H. H. Whetzel, Dr. L. R. Hesler, Dr. Donald Reddick, Dr. V. B. Stewart, Dr. C. T. Gregory, Dr. H. M. Fitzpatrick, and Miss Edwina Smiley. W. Howarp Rankin. Cornett University, Iraaca, New YORK, September 1, 1918. CONTENTS CHAPTER I SEEDLING DISEASES AND INJURIES . Damping-off Sun-scorch Winter-drying Freezing-to-death Smothering-disease CHAPTER II Lear DISEASES AND INJURIES Winter-drying Late frost-injury Drought-injury and aumscondls . Smoke- and gas-injury Leaf-spots ‘ Powdery mildews Leaf-cast of conifers . Sooty molds Silver-leaf . CHAPTER III Bopy AND BraNncH DISEASES AND INJURIES . Freezing-to-death of iba and bark . Frost-cracks Fi Sun-seald . . Lichen-injury . . Slime-flux . Mistletoe diseases Electrical injuries x CONTENTS Galls ‘i : 4 . Wood-rots 2 < : : CHAPTER IV Root Diseases aND INJURIES Drying and drowning Freezing-to-death Gas-injury . Shoe-string root-rot Mycorhizas Roots parasitized by flowering plants CHAPTER V ALDER DISEASES Powdery mildew of aankite Catkin-deformation Brown checked wood-rot Common white wood-rot Root-tubercles . CHAPTER VI ARBorR-VITZ DISEASES Seedling-blight . Leaf-blight Brown pocket heartwood-not Red-brown root- and butt-rot CHAPTER VII AsH DISEASES . Leaf- and twig-rust White heartwood-rot CHAPTER VIII Bap Cypress Disrases : Pecky heartwood-rot ‘ ‘i - «. 64 97 CONTENTS CHAPTER IX Basswoop DIsEAsEs Powdery mildew Leaf-spot . White sapwood-rot Southern root-rot CHAPTER X BrrecH DIsEAsES Yellowish sapwood-rot Common white wood-rot Uniform white sapwood-rot White butt-rot . Parasitized roots CHAPTER XI Birco DIsEasEs Leaf rust . Yellow leat-blister Red leaf-blister . Powdery sapwood-rot Yellowish sapwood-rot Common white wood-rot Brown heartwood-rot White butt-rot . CHAPTER XII BucKEYE DISEASES Leaf-blotch Powdery mildew : Curled leaf-blight and witches’ Shroam White sapwood-rot CHAPTER XIII ButTERNUT DISEASES 4 ‘ . Leaf-spot . : eg. ff = cs 123 123 xil CONTENTS Common white wood-rot Brown checked wood-rot CHAPTER XIV CaTALPA DISEASES Yellowish wood-rot Brown butt-rot . CHAPTER XV CEDAR DISEASES Eastern leaf-rust Western leaf-rust Brown felt-blight Eastern witches’-broom . Western twig-blight and witches’ Serban Branch-swellings : Pecky heartwood-rot CHAPTER XVI CHESTNUT DISEASES Large leaf-spot . Twig-blight Endothia canker Strumella canker : Brown checked wood-rot . Straw-colored heartwood-rot White piped butt-rot CHAPTER XVII Em DIstases Leaf-spot Powdery mildews Brown wood-rot CHAPTER XVIII Fir DIsgases . . ‘ Leaf blister-rusts ‘ : CONTENTS xill PAGE Leaf-rusts . ‘ ' é é ‘ : F i : . 159 Leaf-cast . , * j 3 ; ‘ ‘ 3 : . 159 Rust witches’-broom . . : ; : 3 Fi i . 160 Gray mold twig-blight =. F ‘ . A ; : . 161 Mistletoe burl and witches’-broom . : . : : . 163 Pecky wood-rot . : : ‘ : : : : ‘ . 168 Red-brown sapwood-rot . : 3 ; F 5 F . 165 Stringy red-brown heartwood-rot ‘ F ‘ F . 166 Brown pocket heartwood-rot_.. F s F “ ‘ . 168 Brown heartwood-rot ‘ : + : 3 ‘ ; . 169 Brown root- and butt-rot . : : : ‘ : ‘ . 169 Red-brown root- and butt-rot . ° 3 ‘ ‘ ‘ . 170 Yellow root-rot . F : i ‘ . - 5 . 170 CHAPTER XIX Hackserry DISEASES k Z 3 : : . : . 173 Powdery mildews. : ‘ : : , : < . 178 Witches’-broom ‘ é ; , : ‘ R F . 174 CHAPTER XX Hemtock DISEASES : : J 3 . : s ‘ . 177 Seedling root-rot = 3 ‘ ‘ e 3 F . . 177 Leaf-blight . ; ‘ ‘ ‘ ‘ ‘ ; . 179 Brown-mold leaf-blight ; : . F ‘i ; ‘ . 180 Leaf and cone blister-rusts : , m ‘ 4 : . 180 Leaf-, cone- and twig-rusts 4 & F ‘ F . . 182 Red-brown sapwood-rot_ . : - . ies th ‘ . 184 Stringy red-brown heartwood-rot . - + + - . 184 Brown pocket heartwood-rot_. ‘ ‘ ; ; ‘ . 184 Cuboidal wood-rot_. 5 . eo. % " : ‘ . 185 Red-brown root- and butt-rot_ . : 5 , $ ‘ . 187 CHAPTER XXI Hickory DISEASES . ‘ : ‘ ‘ E J : . 188 Leaf-mildew and witches’ i . ‘ ‘ s 4 . 188 Common white wood-rot . ‘ 5 ; F : : . 189 xiv CONTENTS CHAPTER XXII PAGE JUNIPER DISEASES . : . : : 3 . ‘ : . 190 Seedling twig-blight . : : ‘ B 5 ‘i , - 190 Leaf- and stem-rusts (general) . . . ‘ : . . 192 Leaf- and twig-rusts . . : ; ; : 3 . . 196 ‘Cedar-apples : : : ‘ : F : : . 197 Rust witches’-brooms : : é ‘ F ‘ - . 200 Branch-galls «© ; . 7 : 3 : . 200 Fusiform branding. : ‘ . : 3 5 . 202 White bark % : 4 ‘ ‘ F ‘ ‘ . 204 Brown pocket hearewaodetnt ‘ 2 . ‘ é i . 204 White pocket heartwood-rot_ .. ‘i ‘ ‘ ‘ : . 206 Yellow wood-rot . ‘i ‘ 3 : ‘ ‘ , . 208 Stringy brown wood-rot . : : : : : . . 209 Basal heartwood-rot . ‘ a s : ‘ ‘ 5 . 210 CHAPTER XXIII Larca DIsEAsEs. z 3 . ‘ “ 3 % . 212 Seedling root-rot ; : : ; mace A 3 . 212 Leaf-rusts . ‘ ; A F ‘ 5 . 212 Mistletoe burl and witches’ Pemoon ‘ : 2 F 5 . 214 Pecky wood-rot ‘ : . ‘ - a - ‘ . 215 Red-brown sapwood-rot_ . : : 3 . ‘ . 215 Brown heartwood-rot - a ; F ¢ ‘ ‘ . 216 Brown pocket heartwood-rot . : ‘ 5 F , . 217 Red-brown root- and butt-rot . ‘ x : 3 : . 217 Yellow root-rot . ‘é ; ‘ ‘ ‘ P 5 3 . 218 CHAPTER XXIV Locust DisEasEs . . : 3 : : A : : . 219 Yellow wood-rot : : : ‘ ; a ‘ : . 219 Brown checked wood-rot . - - : : : ' . 221 Root-tubercles . ; ‘ ‘ ‘ a F . ¢ . 222 CHAPTER XXV Map te DISEASES. A ‘ < - : . ‘ ‘ » 223 Tar leaf-spot ‘ 5 : . 228 CONTENTS xv PAGE Black-specked sata . ‘ ‘ : : i i . 225 Leaf-spots . i . , : i ‘ F 4 . 226 Powdery mildews. . A 7 F ‘ ‘ P . 227 Leaf-blight ‘ ‘ ‘ : é 3 ; < . 228 Canker. ‘ z : 3 F : : , . 229 Wilt . . - ‘ : , : . ‘ . 231 Common white srood-rot : ; : . . : ‘: «282 Brown checked wood-rot . P : : ; 2 « 232 White strand wood-rot : : ; ‘ ‘ s : . 233 Uniform white sapwood-rot 5 é : 3 ‘ : . 234 White streaked aaa ‘ 2 : ‘ : ‘ . 235 White butt-rot . . 4 . F ‘ A : . 236 CHAPTER XXVI Oak DISEASES . ‘ ‘ , ; 3 5 z : . 237 Leaf-blight i ‘ é ; . f . : : . 237 Leaf-blister é : , : r : ¢ F ‘ . 239 Powdery mildews. . : : : ‘ : . 241 Brown mildew . 2 : . . : . i . . 248 Large leaf-spot . : é . ' . - ‘ : . 243 Twig-blight . F : 7 : ‘ ° ‘ ‘ . 244 Strumella canker : . : F i ‘ é "i . 245 Brown checked wood-rot_ . < . ‘ - A ‘ . 247 Common white wood-rot . j é ; : , 5 . 250 White pocket heartwood-rot_ .. ; : : : ; . 250 String and ray butt-rot_.. ‘ : : : ‘ : . 252 Wet heartwood-rot_ . . : é é ‘ ‘ i . 254 Honeycomb heartwood-rot - : . - : - . 255 Soft heartwood-rot . , : ; : : F 2 og 257 White piped butt-rot . F ‘ : 7 ‘ a : . 258 Straw-colored butt-rot é : 2 F : 3 ‘ . 259 White wood-rot . r ‘ : : F : : 5 260 White butt-rot . 3 ‘ “ i . ‘ 3 3 . 260 White root-rot . . , : : : ‘ . . . 261 CHAPTER NXVII Pine DISEASES 5 ‘9 ‘ . ‘ : : . 264 Seedling root-rot i : : : f ‘ i : . 264 Xvl CONTENTS PACE Leaf blister-rusts é . = ‘ é . ‘ Ne 265 Leaf-rust . . . ‘ ‘ ‘ 7 is . 270 Leaf-cast of white pine . . . : . ‘ : - 270 Brown felt-blight . 5 . 271 Leaf-cast and witches’ vee of qitern igellow ce ‘ - 271 Twig-blight . 4 3 ‘ ‘ ‘ z . 272 Mistletoe burls and witdlies Lifosnis : ‘ ‘ 5 « 273 Blister-rust of five-needle pines . : : . “i . 274 Sweet-fern rust . : ; : s 3 ‘ - . 281 Comandra’ : js ‘ ‘ < : ‘ i . 283 Castillejarust . . : - ‘ a : 2 ‘ - 285 Oak rust . 5 7 x ‘ 7 ‘ 2 : . . 287 Pifion blister-rust : : d F - F : ‘ . 290 Basal canker. - z ; F . r p ‘ . 290 Pecky wood-rot F f : : ‘ : = d . 291 Red-brown sapwood-rot_ . : : Z : j 5 . 292 Brown heartwood-rot 3 : ; F . 3 : . 292 Brown pocket heartwood-rot.. . : : : ‘ . 293 Red-ray wood-rot_ . : : : 3 : 2 . 293 Red-brown root- and buttrot ‘ - : : : i . 294 Yellow root-rot . 7 : ‘ : ‘ : ‘: # . 296 Brown root- and butt-rot . . - , : Fs 7 . 296 CHAPTER XXVIII PoptarR DISEASES . : , ‘ ‘ : é 3 : . 298 Leaf-rusts . GP ins ‘ : ; : 3 : : . 298 Powdery mildew F ‘ 5 : : . ‘ < . 800 Yellow leaf-blister . A ‘ e 5 ‘ 5 ‘ . 3800 Catkin-deformation . e ‘ : ‘ : : -* . 3801 Canker. : : 7 : : s ‘ j . . 3801 Limb-gall . ‘ : é : ; ‘ : i : . 304 Common white wood-rot . : : _ : . . 3804 White pocket heartwood-rot .. : ‘ : : A . 310 White butt-rot . F : . : ‘ P - A . 310 CHAPTER XXIX Spruce Diseases. j : : 3 . . : é . 313 Seedling twig-blight . ‘ F . i ‘ 5 3 . 313 CONTENTS Leaf blister-rusts Leaf-rust . : Brown felt-blight Leaf- and twig-blight Cone-rust . Rust witches’ cbnesnis. Mistletoe witches’-broom . Pecky wood-rot Red-brown sapwood-rot Stringy red-brown heartwood-r et Brown pocket heartwood-rot Cuboidal wood-rot ‘ Brown root- and butt-rot . Red-brown root- and butt-rot Yellow root-rot . CHAPTER XXX SycaMORE oR PLANE TREE DISEASES Leaf- and twig-blight CHAPTER XXXI WALNUT DISEASES . Leaf-spot . Common white woud-rot Brown checked wood-rot CHAPTER XXXII WILLOW DISEASES Powdery mildews Leaf-rusts . Tar leaf-spot Common white wood-rot White wood-rot CHAPTER XXXII TREE SURGERY Pruning XVIii PAGE 315 316 317 319 320 320 321 324 327 328 328 329 329 331 3381 333 333 339 339 339 340 341 341 341 343 343 344 345 346 XVili CONTENTS Disinfecting wounds . Wound dressings Lesion excision . Cavity treatments CHAPTER XXXIV SPRAYING AND DusTING For LEAF DISEASES APPENDIX Common names of trees Synonymy of polypore names Glossary . ‘ : - : : General bibliography of tree diseases . INDEX PAGE 348 348 351 353 357 361 361 364 365 367 371 $2: COS Oe Or BOs on ILLUSTRATIONS Frost-crack in a maple Frost-crack healed over in summer Mistletoe growing on white fir . Galls on branch of oak Polypore fruiting-body showing spores Shoe-string root-rot on pine : Young toadstools of Armillaria wth : Mature fruiting-body of phi root-rot fungus . Ashrust . Leaf-spot of basswood, (by v. B. ‘Steven . Fruiting-body of Fomes fomentarius Beech wood decayed by Fomes applanatus Fruiting-body of Polyporus betulinus Leaf-blotch of horse chestnut . Leaf-spot of butternut . Brown felt-blight Endothia canker of chestnut Mycelial fans between bark and wood Spore-horns of chestnut canker fungus . Perithecial stage of chestnut canker fungus . Leaf-spot of elm (by H.,.M. aaa . Powdery mildew of elm . Pecky wood-rot, early stage . Pecky wood-rot in Douglas fir . Fruiting-body of Echinodontium tinctorium . Brown heartwood-rot of Douglas fir . ‘ . Fruiting-bodies of Rhizina undulata (after Fitzpatrick) . Cuboidal wood-rot of hemlock (by G. F. Atkinson) . Cedar-apple fungus on wild apple leaves (after Weimer) . Cedar-apple fungus on haw leaf - . Cedar-apples,— early stages of development (after Wehner . Cedar-apples in late autumn (after Weimer) . Cedar-apple in spring with spore-horns (after Woiuues) xix XX ILLUSTRATIONS PAGE 34, Fruiting-bodies of Fomes roseus . F é . 3 - 205 35. Fruiting-body of Fomes rimosus F ; ‘ F : - 220 36. Tar leaf-spot of maple ; . 7 . 224 37. Leaf-spot of maple caused by Phillosiein x minima. 226 38. Leaf-spot of maple caused by ink a aka H. M. Fitzpatrick) e 8 = 227 39. Leaf-blight of maple . ; ls : : ‘ _ é . 228 40. Nectria canker on maple . . : : > . 229 41. Sections through Nectria canker on maple: ‘ : . . 230 42. Sections through trunk of maple affected by wilt : : . 231 43. Section through fruiting-body of Hydnum septentrionale . . 235 44. Leaf-blight of oak ; ‘ 2 3 . 238 45. Leaf-blister of oak (by H. H. Whetzel) ; & of <« 239 46. Powdery mildew on oak leaf (by G. F. Aiistison) F F . 242 47. Twig-canker on oak . F . 244 48. Brown checked wood-rot in Scale ‘Oy G. F. ‘AMiioseib: ‘ . 248 49. Fruiting-bodies of Polyporus sulphureus F : : . 249 50. Fruiting-body of Polyporus Berkeleyi : Z : : . 258 51. Fruiting-body of Polyporus dryadeus : 262 52. Blister-rust on twig of white pine (after Hédler andl Whetzel) 276 53. Blister-rust on trunk of white pine . " 277 54. Uredinial stage of Cronartium ribicola on currant (after Hedler ad Whetzel) .. 278 55. Telial stage of Conant Gis on Gan (after Hele: orl Whetzel) . : : : ‘ ‘ ‘ a . 278 56. Blister-rust on lodgepole ae ‘ ‘ : : . ‘i . 286 57. Limb-galls on poplar : : . 3804 58. Common ‘white wood-rot (after Heder and. Whetzel) ; . 3806 59. Fruiting-body of Fomes i agniarius ‘ 307 60. Fruiting-body of Fomes igniarius (form galled Foie ner 308 61. Section through fruiting-body of Fomes igniarius . ‘ . 309 62. Witches’-broom on black spruce , - : ‘ . 3822 63. Mistletoe witches’-brooms on black spriiée: ‘ ‘ ‘ . 323 64. Pecky wood-rot in spruce . : ‘ 5 é , : . 825 65. Pecky wood-rot, advanced stage Fi A : 7 . 3826 66. Leaf-blight of sycamore. 334 67. Sycamore tree defoliated by leaf- blight fungus wey M. FE. Barnus) 325 68. Cankers on small sycamore twigs : 336 69. Cankers on limbs of sycamore . : . 337° 70. Powdery mildew on willow leaves (by G. F. Aitleingon), é . 3842 MANUAL OF TREE DISEASES MANUAL OF TREE DISEASES CHAPTER I SEEDLING DISEASES AND INJURIES From the very beginning of the life of a tree, the seedling is subject to many more or less serious diseases. Damping-off may cause death, even before the tiny plant has grown above the surface of the soil. Later, if damping-off is avoided, va- rious blights are common in the seed- and transplant-bed. Although many pathogenes are known to cause seedling dis- eases, it is very difficult for the layman to identify the trouble any more accurately than by the general symptoms of damping- off or blight. Damping-off symptoms are mostly due to the activities of specific soil-harbored fungi. Blight symptoms may be produced by various rapidly spreading fungi, or by adverse moisture and temperature conditions. After a careful comparison of the blight symptoms produced by environmental conditions, with the usual symptoms caused by parasites, the layman should be able to distinguish between these two general types of seedling blights. In some cases, the seedlings of certain kinds of trees are affected by well-known specific leaf-, stem- or root-parasites which cause blight. These dis- eases are described in the chapter on the diseases of the species of tree affected. Otherwise, the damping-off and blights such as sun-scorch, winter-drying and freezing-to-death of seedlings of both coniferous and deciduous trees, are treated below. B 1 2 MANUAL OF TREE DISEASES Dampinc-OFF Caused by various species of fungi The damping-off diseases have commanded serious atten- tion from all persons who have attempted to grow seedlings, especially of conifers. Schreger, in an early compilation of the facts known about tree diseases, published in 1795, writes about the damping-off of beech seedlings. Since the growing of large quantities of seedlings for forest planting was first attempted in Europe, the earlier literature on damping-off appeared mostly in foreign languages. American nurserymen have grown small quantities for ornamental and shade tree stock for many years. The increasing demands for large quantities for forest planting were not supplied, however, by the production of the commer- cial nurserymen. It is thought that the small quantity pro- duced and high prices demanded for the stock were due mainly to the difficulties of handling the damping-off diseases. To-day the growing of coniferous seedlings in federal and state nurseries has developed until millions of trees are produced yearly. It was during the development of these specialized nurseries that the damping-off diseases in this country were studied, and methods evolved for their control. Damping-off is a universal seedling trouble. The fungi causing the disease are common soil-harbored organisms asso- ciated with decaying plant material. Seedlings grown in new soil may suffer from damping-off as severely as those in beds which produced diseased plants the previous year. The seed- lings of coniferous trees in general show marked susceptibility, while those of deciduous trees are less often attacked. Beech and maple seedlings, however, often suffer. When no pre- cautions are taken, damping-off may kill practically the entire stand of seedlings, especially when large numbers are grown under crowded conditions. SEEDLING DISEASES AND INJURIES 3 Symptoms. The critical period in the development of tree seedlings, so far as damping-off is concerned, extends from the time of the gerimination of the seed until the stem-tissues become woody, . —a period of one or two months. Usually the first indication of damping-off is a water-soaked or brown area of decaying tissue in the stem, near the surface of the ground. If the dis- ease occurs very early in the development of the plants, the stems may be killed before their tips emerge from the ground. Often, also, the lesion originates just below the surface of the soil after the plant has pushed out, and wilting of the plant is the first sign of the trouble. Wherever the lesion may occur, the diseased stem-tissue soon collapses and allows the plant to fall over, while further disintegration of the tissue results in the death of the seedling. Root-rot may accompany damping- off and often is only another indication of the work of the same fungus. In the case of deciduous trees, especially the beech, the first lesions may show as cotyledon-spots. These lesions soon enlarge, however, so that the stem is involved and damping- off follows. Under conditions favorable for the development of damping-off fungi, large circular areas of dead plants appear and only a few days are sufficient for the spread of the patho- gene from a few centers to all parts of the seed-bed. Cause of damping-off. Numerous species of fungi have been found to cause damp- ing-off. In general these fungi have no restricted host-range, and are so prevalént and omnivorous that seedling crops uni- versally suffer. In this country most of the work on these diseases has been done with conifers. Numerous species and forms of fungi belonging to the genus Fusarium have been found to be the most common cause. Pythium debaryanum Hesse and species of Rhizoctonia have also been found to be important damping-off pathogenes in certain cases. In Europe, 4 MANUAL OF TREE DISEASES Phytophthora omnivora de Bary is the most common on both coniferous and deciduous tree seedlings. This latter fungus is widely distributed in this country and may be found to be of importance with further investigations on deciduous seedlings. - It is to be assumed that many other species of fungi may also at times produce damping-off in tree seedlings, since Thielavia basicola (B. and Br.) Zopf and species of Botrytis, Colle- totrichum, Volutella and other fungi have been discovered producing this disease in seedlings of other crops. Numerous inoculation experiments by various workers have established the power of the above mentioned pathogenes to cause this . type of disease. The causal fungi represent many widely different types of life history. The parasitism of these fungi is of a very primi- tive sort. This is evidenced by their usual saprophytic char- acter, extreme destructiveness to the host-plant, wide host- range and the fact that they are limited in their activities to very young seedlings, which have not developed the more com- plex physical and chemical nature of older plants. These fungi exist ordinarily as common saprophytes on decaying vegetable matter in the soil and -thus their mycelium is the main infective material. Various types of spores are formed by the different species of fungi concerned in damping-off, but they are rarely instrumental in the inoculation of healthy plants. These spores, however, are mainly useful in carrying the fungus over winter and through other conditions detrimental to vegetative growth. The entire life history of these fungi then, so far as explaining the appearance and development of damping-off in seedling-beds, is confined largely to the growth of the mycelium through or on the surface of the soil, from one plant to another. This manner of spreading is often well il- lustrated when all the plants in a single row are destroyed and only occasional plants in the adjacent rows are affected. Al- though some one or several of the damping-off fungi are generally SEEDLING DISEASES AND INJURIES 5 present in all soils, their presence may not become evident if conditions are adverse to their development. All damping-off pathogenes are markedly influenced by temperature, soil moisture and the humidity of the atmosphere. A relatively high temperature, moist and compact soil and a humid at- mosphere furnish ideal conditions for these fungi, while lower temperatures and drier conditions of soil and atmosphere may check successfully a destructive development of these organisms after some damage has already been accomplished. Control. Since damping-off may be caused by any one of numerous species of fungi and may occur under such variable conditions, no general rules for treatment can be prescribed which will apply in all cases. The control of damping-off may be effected by one of two general methods: (1) protection of the seedlings by maintaining conditions of temperature and moisture which interfere with the destructive development of the pathogenes ; (2) eradication of the pathogenes from the soil of the seed-bed by means of disinfectants. (1) Protection. Every investigator agrees that much can be accomplished in the control of damping-off by giving careful attention to the manipulation of soil moisture, temperature and atmospheric humidity. At the same time, it is realized that one may find it difficult, in regulating the amount of moisture and other factors, to preserve the equilibrium necessary to grow seedlings, and at the same time to prevent the growth of the fungi. The following method of procedure is advised : Each seed-bed should be provided with upright frame, with wire-mesh sides and removable top, which can be made into half-shade or full-shade by laying on laths. The seed should be sown on the surface of the prepared soil and covered to the desired depth with clean dry sand 6 MANUAL OF TREE DISEASES obtained by digging three or four feet below the surface. This furnishes a surfacing for the bed which is sterile and easy to keep relatively dry. The beds should be covered and kept moist enough to pro- mote germination. After the seeds have germinated, partial shade should be furnished on bright days but should be removed in cloudy weather, in order to allow as much evaporation as possible from the surface of the soil. These precautions are especially important if it is warm and rainy. If the surface of the soil does not dry sufficiently, more clean coarse sand may be scattered over it. (2) Eradication. Two general eradication methods are recommended for the control of damping-off: (1) disinfection of the soil before planting, usually with formaldehyde; and, (2) for coniferous seedlings only, disinfection at the time of planting with sulfuric acid. If damping-off has previously occurred in a bed, the best practice is to remove the top-soil and substitute new soil. This is desirable since a large accumulation of the resting spores of the causal pathogene is to be expected after a severe outbreak. The following steps are essential for thorough disinfection : A solution of formalin should be made by adding one gallon of formalin (which should contain forty per cent formaldehyde by volume) to fifty gallons of water. The soil should be prepared by forking or raking. The formalin solution may then be applied to the bed with a sprin- kling-can, using about two quarts for every square foot of soil to be treated. If the nature of the soil is such that this amount cannot be put on in one application, as much as possible should be applied without making the soil muddy and the remainder added a few hours later. The bed should be covered as securely as possible with heavy paper or other impervious material for forty-eight hours. SEEDLING DISEASES AND INJURIES 7 The active substance in the formalin solution is liberated as a gas (formaldehyde). The cover is necessary in order to retain this gas in the soil for a period sufficient to kill the pathogenes. Three or four days after the cover is removed, the soil should be thoroughly forked and allowed to stand in a loosened con- dition for another day or two, after which the bed may be prepared for sowing the seed. It is important to time the application of the formalin so that the seed may be sown as soon as the operations above described are completed, since the soil may become contaminated again from surrounding soil. Experience shows that beds contaminated after dis- infection may exhibit greater loss than those not disinfected. The increased virulence of damping-off fungi in disinfected beds is thought to be due to the lack of competition with other soil organisms which have been killed by the disin- fectant. With ordinary care, however, under most condi- tions a clean crop of seedlings is assured if the disinfection is thorough. Even after carefully disinfecting the soil, all the measures advised above under Protection should be ob- served (see page 5). The application of sulfuric acid to the soil at the time of seeding has given good results in controlling damping-off in coniferous seed-beds. Sulfuric acid should never be used on deciduous seedlings. The amount of acid used with safety will necessarily vary with the natural acidity or alkalinity of the soil. A too heavy application of sulfuric acid will cause injury to the seedlings. This method is more difficult to handle than the formalin treatment because in loose sandy soils the capillary movement of the water will bring the ‘acid to the surface and produce there a concentrated solution, which must be counteracted by daily watering. With heavier soils, no wa- tering seems necessary from the experiments so far reported. With the two uncertain factors in mind, the natural acidity or alkalinity and the physical nature of the soil to be treated, 8 MANUAL OF TREE DISEASES the grower must experiment under his own conditions before applying this method generally, else the chemical injury by the acid to the seedlings may be greater than the losses due to damping-off if no treatment were used. If this method can be handled without damaging the seedlings, two special ad- vantages are gained over the other two methods given above. In the first place, dicotyledonous weeds rarely grow in the acid soil and the saving of the expense of weeding will often pay for the treatment. Secondly, the disinfectant is present in the soil throughout the critical damping-off period. This assures complete control sincé contamination of the beds from neigh- boring soil is not possible and, moreover, conditions of tempera- ture and moisture favorable to seedling growth can be provided without danger. The average amount of sulfuric acid is three-sixteenths of a fluid ounce of clear commercial sulfuric acid to each square foot of soil to be treated. A solution is made by adding three- sixteenths of an ounce of the sulfuric acid to each quart of water (this is at the rate of one part of acid to 170 parts of water). This solution should then be applied when the seed is sown at the rate of one quart to each square foot of soil. If the soil is light and sandy and conditions are favorable for excessive evaporation, light watering once or twice a day may be neces- sary to prevent acid-injury. In heavier soils no watering may be necessary. The strength recommended above is suffi- cient to disinfect a soil which is not strongly alkaline. If the soil is naturally acid, the three-sixteenths of an ounce to each square foot may be too much. It would, therefore,-be advisable to divide a given bed into three parts, applying sulfuric acid to each part respectively in the following quantities, one-eighth, one-fourth and three-sixteenths of an ounce in a quart of water to each square foot. From this experiment it may be deter- mined which strength can be safely employed under the exist- ing soil conditions. SEEDLING DISEASES AND INJURIES 9 REFERENCES ON Dampinc-Orr Hartley, Carl, and Pierce, R. G. The control of damping-off of conif- ans seedlings. U.S. Dept. Agr. Bul. 453 : 1-32, pls. 1-2, fig. 1. Johnson, James. The control of damping-off disease in plant beds. So Agr. Exp. Sta. Research Bul. 31: 29-61, figs. 1-12. Gifford, C. M. The damping off of coniferous seedlings. Vermont Agr. Exp. Sta. Bul. 157 : 148-171, pls. 1-4, figs. 1-10. 1911. Jones, L. R. The damping off of coniferous seedlings. Vermont Agr. Exp. Sta. Ann. Rept. 20 : 342-347. 1908. Hartley, Carl. Injury by disinfectants to seeds and roots in sandy soils. U.S. Dept. Agr. Bul. 169: 1-85, pl. 1, figs. 1-2. 1915. Spaulding, Perley. The damping-off of coniférous seedlings. Phyto- pathology 4: 73-88, pl. 6, figs. 1-2. 1914. Hartley, Carl, and Merrill, F.C. Preliminary tests of disinfectants in controlling damping-off in various nursery soils. Phyto- pathology 4: 89-92. 1914. Pettis, C. R. Problems in nursery practice. Proc. Soc. Amer. Fores- ters 4: 48-44. 1909. Scott, Chas. A. » 156. Pseudotsuga, see Fir. Pteridis, Uredinopsis, 157. Puccinia fraxinata, 93. Pucciniastrum minimum, 180. myrtilli, 180. pustulatum, 157. Puck of cypress, bald cypress, 97. punctatum, Rhytisma, 225. purpureum, Stereum, 41. pusilla, Razoumofskya, 321. pustulatum, Pucciniastrum, 157. pyriforme, Peridermium = Cronartium comandre, 283. pyrole, Melampsoropsis, 320. Pythium debaryanum, 3. seedlings, gen- INDEX Q Quercus, see Oak. quinqueseptata, Herpotrichia, 317. R radicata, Sparassis, 170, 218, 296, 331. radicicola, Bacillus, 88, 222. Razoumofskya, host index to, 55. see Mistletoe diseases, general, 54. R fskya americana, 273. campylopoda, 273. Douglasti, 163. laricis, 214. pusilla, 321. Red-brown root- and butt-rot, arbor- vite, 91. fir, 170. hemlock, 187. larch, 217. pine, 294. spruce, 331. Red-brown sapwood-rot, fir, 165. hemlock, 184. larch, 215. pine, 292. spruce, 327. Red-heart, pine, 293. Red leaf-blister, birch, 112. Red-ray wood-root, pine, 293. Red-rot, fir, 163. —~ see Pecky wood-rot. see Red-ray wood-rot. Reinforced dressings, 351. Reinforcing for cavity filling, 355. Rheades, Polyporus, 250, 310. Rhizina undulata, 177, 212, 264. Rhizoctonia, see Damping-off, 2. Rhytisma acerinum, 223. punctaium, 225. salicinum, 3438. ribicola, Coleosporium, 269. Cronartium, 274. rimosus, Fomes, 219. Ring-shake, fir, 163. see Pecky wood-rot. Robinia, see Locust. Root diseases and injuries, 72. drowning, general, 73. drying, general, 73. freezing-to-death, general, 74. INDEX Root diseases and injuries — Continued gas-injury, general, 76. mycorhizas, general, 82. roots parasitized by flowering plants, general, 84. shoe-string root-rot, general, 78. Root-rot, brown, fir, 169. pine, 296. spruce, 329. red-brown, arbor-vitse, 91. fir, 170. hemlock, 187. larch, 217. pine, 294, spruce, 331. seedling, hemlock, 177. larch, 212. pine, 264. see Damping-off, 2. shoe-string, general, 78. southern, basswood, 103. ‘ linden, 103. : white, oak, 261. yellow, fir, 170. larch, 218. pine, 296. spruce, 331. Root-tubercles, alder, 88, 222. Rosellinia sp?, see Brown-mold leaf- blight, 180. roseus, Fomes, 91, 168, 184, 204, 217, 293, 328. Rust diseases. blister-rusts, blueberry, leaf, fir, 157. Castilleja, pine, 285. Comandra, pine, 283. cone-, leaf- and, hemlock, 180. fern, leaf, fir, 156. ! fireweed, leaf, fir, 157. five-needle pines, 274. leaf- and cone-, hemlock, 180. leaf, fir, 155. : pine, 265. spruce, 315. oak, pine, 287. Pifion, 290. ~ sweet-fern, pine, 281. unconnected, leaf, fir, 158. branch-swellings, cedar, 134. juniper, 202. cedar-apples, juniper, 197. 393 Rust diseases — Continwed cone- and twig-, leaf-, hemlock, 182. cone-, spruce, 320. eastern leaf-, cedar, 129. eastern witches’-broom, cedar, 131. galls, juniper, 200. leaf- and stem-, juniper (general), 192. leaf- and twig-, ash, 93. juniper, 196. leaf-, birch, 111. cone- and twig-, hemlock, 182. eastern, cedar, 129. fir, 159. larch, 212. poplar, 298. spruce, 316. western cedar, 130. willow, 341. poplar, leaf, fir, 159. stem-, leaf- and, juniper (general), 192. twig-blight and witches’-broom, western, cedar, 133. twig-, leaf- and, ash, 93. juniper, 196. twig-, leaf-, cone- and, hemlock, 182. western leaf-, cedar, 130. western twig-blight and witches’- broom, cedar, 133. willow, leaf, fir, 159. witches’-broom, eastern, cedar, 131. fir, 160. juniper, 200. spruce, 320. western twig-blight and, cedar, 133. 8 salicinum, Rhytisma, 343. | salicis, Uncinula, 300, 341. | Sapwood-rot, general, 64. powdery, birch, 113. red-brown, fir, 165. hemlock, 184. larch, 215. pine, 292. 5 spruce, 327. # uniform white, beech, 198. maple, 234. 394 Sapwood-rot — Continued white, basswood, 103. buckeye, 122. linden, 103. white streaked, maple, 235. yellowish, beech, 105. birch, 115. Schweinitzit, Polyporus, 91, 170, 187, 217, 294, 331. Sclerotinia Fuckeliana = Botrytis cine- rea, 161. Seedling-blight, arbor-vite, 89. Seedling diseases and injuries, 1. damping-off, general, 2. freezing-to-death, general, 12. root-rot, see Damping-off, 2. smothering-disease, general, 15. sun-scorch, general, 9. winter-drying, general, 11. Seedling, root-rot, hemlock, 177. larch, 212. pine, 264. twig-blight, juniper, 190. spruce, 313. septentrionale, Hydnum, 108, 234. Septoria, see Leaf-spots, general, 27. Sheet metal for cavities, 354. Shoe-string root-rot, general, 78. Silver-blight, leaves, general, 41. Silver-leaf,.general, 41. Slaters’ cement as a wound dressing, 350. Slime-flux, general, 53. Smoke- and gas-injury, leaves, gen- eral, 23. Smothering-disease, seedlings, general, 15. Soft heartwood-rot, oak, 257. solidaginis, Coleosporium, 267. sonchi-arvensis, Coleosporium, 266. Sooty molds, general, 41. Southern root-rot, basswood, 103. linden, 103. Sparassis radicata, 170, 218, 296, 331. Spheropsis malorum, 140, 244. Spheropsoidea, Phyllosticta = Guignar- dia esculi, 118. Spherotheca lanestris, 243. phytoptophila, 174. Spraying and dusting for leaf diseases, 357. INDEX Spruce diseases, 313. blister-rusts, leaf, 315. brown felt-blight, 317. brown pocket heartwood-rot, 328. brown root- and butt-rot, 329. butt-rot, brown, 329. red-brown, 331. cone-rust, 320. cuboidal wood-rot, 329. damping-off, seedlings, general, 2. drought-injury, leaves, general, 22. drowning, roots, general, 73. drying, roots, general, 73. electrical injuries, general, 60. felt-blight, brown, 317. freezing-to-death, roots, general, TA. seedlings, general, 12. twigs and bark, 47. frost-cracks, 50. galls, general, 63. gas-injury, roots, general, 76. smoke- and, leaves, general, 23. heartwood-rot, brown pocket, 328. stringy red-brown, 328. leaf- and twig-blight, 319. leaf blister-rusts, 315. , leaf-cast of conifers, general, 38. leaf-rust, 316. lightning injury, general, 60. mistletoe diseases, general, 54. witches’-broom, 321. mycorhizas, roots, general, 82. pecky wood-rot, 324. red-brown root- and butt-rot, 331. red-brown sapwood-rot, 327. root-rot, brown, 329. red-brown, 331. shoe-string, general, 78. yellow, 331. rust, leaf blister-, 315. leaf-, 316. witches’-broom, 320. sapwood-rot, red-brown, 327. seedling twig-blight, 313. shoe-string root-rot, general, 78. smoke- and gas-injury, leaves, gen- eral, 23. smothering-disease, seedlings, gen- eral, 15. sooty molds, leaves, general, 41. INDEX Spruce diseases — Continued stringy red-brown heartwood-rot, 328. sun-seald, bark, general, 52. sun-scorch, leaves, general, 22. seedlings, general, 9. twig-blight, leaf- and, 319. seedling, 313. winter-drying, leaves, general, 18. seedlings, general, 11. witches’-broom, mistletoe, 321. rust, 320. wood-rot, cuboidal, 329. pecky, 324. wood-rots, general, 64. yellow root-rot, 331. squamosus, Polyporus, 233. Stem-rusts, leaf- and, juniper (general), 192. Stereum purpureum, 41. subpileatum, 255. Straw-colored butt-rot, oak, 259. heartwood-rot, chestnut, 149. String and ray butt-rot, oak, 252. Stringy brown wood-rot, juniper, 209. red-brown heartwood-rot, fir, 166 hemlock, 184. spruce, 328. strobi, Peridermium = Cronartium ribi- cola, 274. strobicola, Hypoderma, 270. Strumella canker, chestnut, 148. oak, 245, Strumella coryneoidea, 148, 245. struthiopteridis, Uredinopsts, 156. suaveolens, Trametes, 344. subpileatum, Stereum, 255. Sulfur dust, 358. sulphureus, Polyporus, 87, 124,149, 221, 232, 247, 340. Sun-seald, bark, general, 52. Sun-scorch, leaves, general, 22. seedlings, general, 9. Surgery, see Tree-surgery, 345. Sweet-fern rust, pine, 281. Sycamore diseases, 333. damping-off, seedlings, general, 2. drought-injury, leaves, general, 22. drowning, roots, general, 73. drying, roots, general, 73. electrical injuries, general, 60. 395 Sycamore diseases — Continued freezing-to-death, roots, general, 74. seedlings, general, 12. twigs and bark, 47. frost-cracks, general, 50. galls, general, 63. gas-injury, roots, general, 76. smoke- and, leaves, general, 23. late frost-injury, leaves, general, 21. leaf- and twig-blight, 333. leaf-spots, general, 27. ‘ lichen-injury, general, 52. lightning injury, general, 60. mistletoe diseases, general, 54. mycorhizas, roots, general, 82. powdery mildews, general, 34. root-rot, shoe-string, general, 78. roots parasitized by flowering plants, general, 84. shoe-string root-rot, general, 78. silver-blight, leaves, general, 41. silver-leaf, general, 41. slime-flux, general, 53. smoke- and gas-injury, leaves, gen- eral, 23. smothering-disease, seedlings, gen- eral, 15. sooty molds, leaves, general, 41. sun-seald, bark, general, 52. sun-scorch, leaves, general, 22. seedlings, general, 9. twig-blight, leaf- and, 333. wood-rots, general, 64. T Taphrina aurea, 300. carnea, 112. cerulescens, 239. Johansonti, 301. Tar, as a wound dressing, 348. Tar leaf-spot, maple, 223. willow, 343. Taxodium, see Bald cypress. “|! Temperature injuries, drought-injury, leaves, 22. freezing-to-death, roots, 74. seedlings, 12. twigs and bark, 47. frost-cracks, 50. 396 Temperature injuries — Continued late frost-injury, leaves, 21. sun-seald, bark, 52. sun-scorch, leaves, 22. seedlings, 9. winter-drying, leaves, 18. seedlings, 11. terebinthinacee, Coleosporium, 269. texanus, Fomes, 209. Thelephora laciniata, 15. Thielavia basicola, 4. Thuja, see Arbor-vitz. thujina, Keithia, 90. Tilia, see Basswood. tilie, Cercospora, 102. Echinodontium, 166, 184, Tools for tree surgery, 346, 352, 353. Top-rot, see red-ray wood-rot. trachysorum, Gymnosporangium, Trametes, pini, 163, 215, 291, 324. suaveolens, 344. ‘ Tree names, common, 361. scientific, 361. Tree surgery, 345. cavity treatments, 353. disinfecting wounds, 348. dressings, wound, 348. lesion excision, 351. pruning, 346. publications on, 369. wound dressings, 348. wounds, disinfecting, 348. trina, Erysiphe, 241. Tsuga, see Hemlock. tsuge@, Keithia, 179. tumefaciens, Bacterium, 304. Twig-blight, chestnut, 140. oak, 244. pine, 272. plane-tree, 333. spruce, 319. sycamore, 333. Twig-blight, gray mold, fir, 161. seedling, juniper, 190. spruce, 313. western, cedar, 133. Twig-rust, leaf- and, ash, 93. leaf- and, juniper, 196. leaf-, cone- and, hemlock, 182. 201. INDEX U ulmarius, Pleurotus, 154. ulmea, Gnomonia, 152. Ulmus, see Elm. Uneinula circinata, 227. Clintonii, 101. flexuosa, 121. macrospora, 153. parvula, 173. polycheta, 173. salicis, 300, 341. Unconnected rusts, leaf, fir, 158. undulata, Rhizina, 177, 212. Uniform white sapwood-rot, beech, 108. maple, 234. Uredinopsis Atkinsonti, 156. mirabilis, 156. osmunde, 156. phegopteridis, 156. pteridis, 157. struthiopteridis, 156. Vv velutipes, Collybia, 103, 122. veneta, Gnomonia, 237, 333. vernonia, Coleosporium, 267. versicolor, Polystictus, 125. Verticillium, wilt, maple, 231. Seats ; 108. Cry 7 PEPYS Volutella, 4. WwW Walnut diseases, 339. brown checked wood-rot, 340. common white wood-rot, 339. leaf-spot, 339. see all diseases listed under Butter- nut diseases. wood-rot, brown checked, 340. common white, 339. Weirti, Chrysomyxa, 316. Poria, 210. Western leaf-rust, cedar, 130. twig-blight and witches’-broom, ce- dar, 133. Wet heartwood-rot, oak, 254. White bark, juniper, 204. INDEX White butt-rot, beech, 108. birch, 117. maple, 236. oak, 260. poplar, 310. White heartwood-rot, ash, 95. White piped butt-rot, chestnut, 150. oak, 258. White pocket heartwood-rot, juniper, oak, 250. poplar, 310. White root-rot, oak, 261. White sapwood-rot, basswood, 103. buckeye, 122. linden, 103. White strand wood-rot, maple, 233. White streaked sapwood-rot, maple, 235. White wood-rot, oak, 260. willow, 344. see common white wood-rot. Willow diseases, 341. common white wood-rot, 343. damping-off, seedlings, general, 2. drought-injury, leaves, general, 22. drowning, roots, general, 73. drying, roots, general, 73. electrical injuries, general, 60. freezing-to-death, roots, general, 74. seedlings, general, 12. twigs and bark, 47. frost-cracks, general, 50. galls, general, 63. gas-injury, roots, general, 76. smoke- and, leaves, general, 23. late frost-injury, leaves, general, 21. leaf-rusts, 341. leaf-spot, tar; 343. leaf-spots, general, 27. lichen-injury, general, 52. lightning injury, general, 60. mistletoe diseases, general, 54. mycorhizas, roots, general, 82. powdery mildews, 341. general, 34. root-rot, shoe-string, general, 78. roots parasitized by flowering plants, general, 84. trusts, leaf-, 341. shoe-string root-rot, general, 78. 397 Willow diseases — Continued silver-blight, leaves, general, 41. silver-leaf, general, 41. slime-flux, general, 53, smoke- and gas-injury, leaves, gen- eral, 23. smothering-disease, eral, 15. sooty molds, leaves, general, 41. sun-scald, bark, general, 52. sun-scorch, leaves, general, 22. seedlings, general, 9. tar leaf-spot, 343. white wood-rot, 344. wood-rot, common white, 343. white, 344. wood-rots, general, 64. seedlings, gen- Willow rust, leaf, fir, 159. Wilt, maple, 231. Winter-drying, leaves, general, 18. seedlings, general, 11. Winter-injuries, see Temperature inju- ries. Witches’-broom, curled leaf-blight and, buckeye, 121. eastern, cedar, 131. hackberry, 174. mistletoe burl and, fir, 163. larch, 214. * pine, 273. mistletoe, spruce, 321. rust, juniper, 200. spruce, 320. western, cedar, 133. western yellow pine, 271. Witches’-broom, see Leaf-cast of coni- fers, general, 38. see Mistletoe diseases, general, 54. Wood-rot, brown, elm, 154. brown checked, alder, 87. butternut, 124. chestnut, 149. locust, 221. maple, 232. oak, 247. walnut, 340. common white, alder, 87. beech, 107. birch, 115. butternut, 124. hickory, 189. 398 Wood-rot — Continued maple, 232. oak, 250. poplar, 305. walnut, 339. willow, 343. cuboidal, hemlock, 185. spruce, 329. pecky, fir, 163. larch, 215. pine, 291. spruce, 324. red-ray, pine, 293. ring-shake, see Pecky. stringy brown, juniper, 209. white, oak, 260. willow, 344. white strand, maple, 233. yellow, juniper, 208. locust, 219. yellowish, catalpa, 125. Wood-rots, cavity treatments, surgery, 353. control of, 70, 351, 353. disinfecting wounds, surgery, 348. dissemination of the spores, 69. INDEX Wood-rots — Continued general, 64. infection, modes of, 65. lesion excision, surgery, 351. see Heartwood-rot. see Sapwood-rot. tree surgery, 345. wood-decay, nature of the process, 67. wound dressings, surgery, 348. Wound, disinfecting, surgery, 348. dressings, surgery, 348. e 2 Yellow leaf-blister, birch, 112. poplar, 300. Yellow root-rot, fir, 170. larch, 218. pine, 296. spruce, 331. Yellow wood-rot, juniper, 208. locust, 219. Yellowish sapwood-rot, beech, 105, birch, 115. Yellowish wood-rot, catalpa, 125. Printed in the United States of America. HE following pages contain advertisements of a few of the Macmillan books on kindred subjects. INJURIOUS INSECTS HOW TO RECOGNIZE AND CONTROL THEM By WALTER C. O’KANE Entomologist of the New Hampshire Experiment Station, and Professor of Economic Entomology in New Hampshire College Decorated Cloth. 414 pages. Over 600 Photographic Illustrations $2.00 Written out of a large scientific knowledge, but in a popular style, this book discusses concisely and yet fully the characteristics, life histories, and means of control of our common injurious insects. The illustrations are from photographs throughout. 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What use to make of your back yard, of your window sills, of your schoolrooms, of your cellar, and your roof for raising food or for learning how to raise food is set out with great detail and with unimpeachable authorities, but in an entertaining manner in the revised “Three Acres and Liberty.” The Fat of the Land By JOHN WILLIAMS STREETER Revised edition, $1.50 At the turn of the season each year there is always an interest in farm books. The appeal of country life is a very real one to thousands of city dwellers, and even if they cannot ever realize their dream, and know that they cannot, they still like to read about those who have turned their faces _ * countryward. Mr. Streeter, in “The Fat of the Land,” tells of the development of a splendid factory farm, and of a well-paying investment out of some land that had been allowed to run down. He puts into concrete form with elaborate detail and abundant figures the practices of the most progressive farmers of to-day, and sets forth the methods of modern scientific agriculture. THE MACMILLAN COMPANY Publishers 64-66 Fifth Avenue New York THE RURAL MANUALS * Edited by L. H. BAILEY Manual of Milk Products Lilustrated, 120, $2.00 By W. A. STOCKING, Jr. Manual of Fruit Diseases Iilustrated, 12mo, $2.00 By L. R. HESSLER and H. H. WHETZEL The Pruning Manual Ilustrated, 12mo, 407 pp-, $2.00 By L. H. BAILEY Manual of Fruit Insects By MARK VERNON SLINGERLAND and CYRUS R. CROSBY Of the New York State College of Agriculture, at Cornell University Illustrated, r2nto, 503 pages, $2.00 A Manual of Weeds By ADA E. GEORGIA Assistant in the Farm Course, New York State College of Agriculture, Cornell University With 385 Illustrations by F. SCHUYLER MATHEWS Lilustrated, cloth, r2mo, 593 pages, index, $2.00 Manual of Farm Animals A PracticaL GuipE To THE CHoosING, BREEDING, AND Keep or Horses, CaTTLz, SHEEP, AND SWINE , By MERRITT W. HARPER Assistant Professor of Animal Husbandry in the New York State College of Agriculture, at Cornell University Illustrated, 12mo, 545 pages, index, $2.00 “A book deserving of close study as well as being handy for reference, and should be in the possession of every farmer interested in stock.” — Aural World, Manual of Gardening A PracticaL GuIDE TO THE MAKING oF Home GrounDs AND THE GROWING OF FLowers, FruITs, AND VEGETABLES FoR Home Use By L. H. BAILEY Mlustrated, cloth, remo, 544 pages, $2.00 This new work is a combination and revision of the main parts of two other books by the same author, “ Garden-Making” and “ Practical Garden Book,” together with much new material and the result of the experience of ten added years, The Farm and Garden Rule Book By L. H. BAILEY Revised and enlarged edition ; illustrated, cloth, r2mo, $2.00 It is essentially a small cyclopedia of ready rules and references packed full from cover to cover of condensed, meaty information and precepts on almost every leading subject connected with country life. THE MACMILLAN COMPANY Publishers 64-66 Fifth Avenue New York re a Ret 2 x arisen an tae aistpootas sha aR PUT ee rea aoe eeu srensanenodtdeeter nace eae ere pn teettee rs rr t ee : : spe par pros - Fer me : . *s ‘ nett F ence er Ee mop ea earth OS eae =a etek Bar heea ry A nreoee Pete tracts