USDA Forest Service - Northeastern Area Archive's Images
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| 304 Images of 139 Subjects | View Subject List | View Image Details | View Thumbnails |
| Image | Subject Name | Scientific Name | Description |
|---|---|---|---|
| 1407041 | human caused injury | Collecting maple syrup is a yearly ritual. Several taps a year will not harm the tree, but too many will strain its recuperative powers and cause internal injury. | |
| 1396096 | royal star magnolia | Magnolia stellata | |
| 1396030 | small pine looper | Eupithecia palpata | |
| 1395004 | skidding | ||
| 1395003 | skidding | Skidder | |
| 1396003 | spruce budworm | Choristoneura fumiferana | parasitized egg mass |
| 1396046 | red pine shoot moth | Dioryctria resinosella | |
| 1395016 | log yard | Air drying yard at sawmill | |
| 1396183 | chanterelle | Cantharellus cibarius | |
| 1398006 | Lophodermium needle casts | Lophodermium spp. | |
| 1398007 | air pollutants | ||
| 1396111 | larger pine shoot beetle | Tomicus piniperda | male and female in gallery |
| 1396004 | spruce budworm | Choristoneura fumiferana | hatched |
| 1396001 | spruce budworm | Choristoneura fumiferana | |
| 1396052 | introduced pine sawfly | Diprion similis | |
| 1396056 | yellowheaded spruce sawfly | Pikonema alaskensis | |
| 1396057 | yellowheaded spruce sawfly | Pikonema alaskensis | |
| 1396065 | red pine shoot moth | Dioryctria resinosella | |
| 1396044 | spruce budworm | Choristoneura fumiferana | |
| 1396090 | northern pine sphinx | Lapara bombycoides | |
| 1396137 | American elm | Ulmus americana | |
| 1396126 | spruce spider mite | Oligonychus ununguis | |
| 1396134 | Armillaria root rot | Armillaria mellea | |
| 1396120 | walnut shoot moth | Acrobasis demotella | |
| 1396116 | red turpentine beetle | Dendroctonus valens | |
| 1396152 | red heart of pine | Phellinus pini | |
| 1396054 | conifer sawfly | Gilpinia frutetorum | |
| 1396156 | cedar-apple rust | Gymnosporangium juniperi-virginianae | |
| 1396080 | Eriophyid mites | Eriophyes spp. | |
| 1396020 | pine spittlebug | Aphrophora cribrata | |
| 1396022 | northern pitch twig moth | Retinia albicapitana | pitch nodule maker, Ottawa Forest |
| 1396051 | red pine sawfly | Neodiprion nanulus nanulus | Chippewa National Forest |
| 1396180 | Helvella fungi | Helvella spp. | |
| 1396157 | cedar-apple rust | Gymnosporangium juniperi-virginianae | |
| 1396182 | stinkhorn mushroom | Phallus impudicus | bisected egg of the fruiting stinkhorn. Note the outer membrane of the egg is a layer of jelly, then a green dusty layer, and within the centre a white spongy mass. |
| 1396160 | porcupine | Erethizon dorsatum | |
| 1396165 | squirrel | Sciurus spp. | cone torn off |
| 1396169 | pocket gophers | pocket gopher damage | |
| 1396133 | Armillaria root rot | Armillaria mellea | |
| 1396135 | Armillaria root rot | Armillaria mellea | |
| 1396159 | porcupine | Erethizon dorsatum | |
| 1396172 | rat, vole, mouse | Coulee Experimental Forest | |
| 1396181 | Helvella fungi | Helvella spp. | |
| 1396170 | pocket gophers | mounds | |
| 1396083 | horned oak gall | Callirhytis cornigera | Shawnee National Forest |
| 1396019 | pine spittlebug | Aphrophora cribrata | fifth instar |
| 1396031 | oak lace bug | Corythucha arcuata | |
| 1396123 | pecan leaf casebearer | Acrobasis juglandis | emerging from case |
| 1396153 | red heart of pine | Phellinus pini | |
| 1396143 | butternut canker | Sirococcus clavigignenti-juglandacearum | |
| 1396144 | Eutypella canker | Eutypella parasitica | Argonne Experimental Forest |
| 1396114 | red turpentine beetle | Dendroctonus valens | in tree struck by lightning. |
| 1396104 | old house borer | Hylotrupes bajulus | |
| 1396061 | bagworm | Thyridopteryx ephemeraeformis | |
| 1396058 | eastern pine weevil | Pissodes nemorensis | |
| 1398025 | conifer seedling weevil | Steremnius carinatus | |
| 1396085 | monarch butterfly | Danaus plexippus | emerged in lab |
| 1407007 | eastern hemlock | Tsuga canadensis | Evergreens have flowers, too. Cones grow from fertilized female cells. When ripe, cones open and scatter their seeds on the forest floor, where a new tree takes root. |
| 1398005 | frost and winter injury (general) | ||
| 1398052 | Dutch elm disease | Ophiostoma ulmi | |
| 1396073 | walkingstick | Diapheromera femorata | |
| 1396074 | walkingstick | Diapheromera femorata | |
| 1396075 | eastern hemlock looper | Lambdina fiscellaria fiscellaria | |
| 1395012 | processing/manufacturing | Portable band mill | |
| 1396038 | pine tussock moth | Dasychira pinicola | |
| 1396040 | maple trumpet skeletonizer | Catastega aceriella | |
| 1395026 | poles, posts, pilings | Posts and poles | |
| 1396072 | carpenter ants | Camponotus spp. | |
| 1396070 | carpenter ants | Camponotus spp. | |
| 1396041 | gall midges | Asynapta spp. | |
| 1396148 | butternut canker | Sirococcus clavigignenti-juglandacearum | |
| 1396045 | red pine shoot moth | Dioryctria resinosella | |
| 1396036 | pine tussock moth | Dasychira pinicola | unhatched egg mass |
| 1396078 | Cynipid gall wasp | Andricus ignotus | gall on oak; agamic generation |
| 1396113 | red turpentine beetle | Dendroctonus valens | |
| 1396139 | Dutch elm disease | Ophiostoma ulmi | |
| 1396039 | maple trumpet skeletonizer | Catastega aceriella | |
| 1396136 | Dutch elm disease | Ophiostoma ulmi | |
| 1396173 | human caused injury | tapping injury | |
| 1396155 | black walnut | Juglans nigra | walnut handling, Wilson Nursery |
| 1396186 | lackluster laccaria | Laccaria laccata | |
| 1396027 | yellownecked caterpillar | Datana ministra | |
| 5050081 | decay | Decay column in red maple. | |
| 5044020 | gypsy moth | Lymantria dispar | Gypsy moth male and female |
| 5038075 | Scleroderris canker of pine and spruce | Gremmeniella abietina | Green staining of G. abietina under the bark. |
| 5052068 | Scleroderris canker of pine and spruce | Gremmeniella abietina | European strain of G. abietina symptoms on red pine. |
| 5038076 | Scleroderris canker of pine and spruce | Gremmeniella abietina | Green stain of wood caused by G. abietina |
| 5037027 | Verticillium wilts | Verticillium spp. | |
| 1409072 | Armillaria root rot | Armillaria mellea | Decay associated with Armillaria mellea in this red spruce did not spread to the center, because it was already altered. The pencil shows where wall 4 separated decayed wood from sound wood that formed after the dead area stopped developing. |
| 1409073 | Armillaria root rot | Armillaria mellea | In this beech root, decay associated with Armillaria mellea was strongly restricted by wall 3 at the red arrows. Again, fungi do not grow at will in a tree. |
| 1409075 | red heart of pine | Phellinus pini | Fomes pini associated with rot produced a wedge of tissue in the bark as indicated by the red arrows. It does not infect healthy sapwood or heartwood, but only wound-altered, resin-soaked, old sapwood and young heartwood, shown by the red dot and letter W, creating a ring pattern. |
| 1409076 | red heart of pine | Phellinus pini | Sound heartwood separates many rings of decayed wood in this pine. The center was probably infected when it was still producing resin. Fomes pini does not grow at will in heartwood must be altered to accomodate the fungus before it can spread. |
| 1409077 | red heart of pine | Phellinus pini | A varient of Fomes pini that occurs in fir on the west coast produced large wedges of infection in the bark. When these wedges coalesce, they will girdle the tree. |
| 1409079 | Strumella canker | Strumella coryneoidea | The seesaw action between this red oak and Strumella coryneoidea went on for many years. The green arrows show where the tree kept the fungus from spreading by producing a wood barrier. At the red arrows a new fungus wedge broke out and began to advance, thus enlarging the canker. |
| 1407068 | sapsucker injury | and food for many species. | |
| 1407004 | flowering dogwood | Cornus florida | or in a cluster of many small flowers, such as this dogwood blossom. |
| 1407005 | eucalyptus | Eucalyptus spp. | Flowers vary widely in their structure and appearance. This eucalypt blossom has an array of showy male parts but not petals. |
| 1407006 | oak | Quercus spp. | On many trees, male and female parts grow separately. These are catkin, the male flowers of an oak. In some species, female flowers grow on one tree and male flowers on another. |
| 1407009 | northern red oak | Quercus rubra | An acorn.... |
| 1407010 | oak | Quercus spp. | becomes an oak, drawing energy from the seed for its first spurt of growth. |
| 1407019 | sugar maple | Acer saccharum | When their work is done, they fall, |
| 1407020 | nutrient cycling | decompose and become part of the soil. | |
| 1407075 | nutrient cycling | and returns to the soil and air, | |
| 1395028 | Specialty forest products | ||
| 1395027 | birch | Betula spp. | Birch tops for specialty (decorative) markets |
| 1395023 | harvesting | whole tree chipping | |
| 1395049 | pulpwood | Unloading hardwood pulpwood at chipping plant in Illinois, 1960. | |
| 1396118 | airplane | U.S.F.S. Beaver plane, 1962 | |
| 1396119 | airplane | U.S.F.S. Beaver plane | |
| 1395059 | charcoal | ||
| 1395056 | charcoal | ||
| 1395058 | charcoal | ||
| 1395052 | charcoal | ||
| 1395053 | charcoal | ||
| 1395054 | charcoal | ||
| 1395055 | charcoal | ||
| 1407003 | yellow-poplar | Liriodendron tulipifera | Life begins for a tree when a male and a female cell meet. These cells may occur together in a single flower, |
| 1407024 | root zone | A tree's life extends beneath the ground. Here, larger roots provide a support system, | |
| 1407025 | root zone | while finer filaments absorb moisture and minerals. | |
| 1407023 | branch union | they, too, fall away.; showing action of natural pruning at the branch union. | |
| 1395062 | slashing and bucking | bucking a log; the tip of the log is elevated so that as the cut is made, the log will fall and the saw blade will not be pinched | |
| 1395064 | felling | cutting a felling notch | |
| 1408052 | Compartmentalization Of Decay In Trees (CODIT) | On these red maple samples, cambial dieback is consistent on all wounds, whether treated or control. | |
| 1407052 | Dutch elm disease | Ophiostoma ulmi | Like all living things, trees eventually die and decay, victims of many living and manmade agents. The agent here is Dutch elm disease. To ward off this widespread infection, keep elm trees well pruned. If they do become infected, cut and destroy the diseased trees as soon as possible. |
| 1409066 | Compartmentalization Of Decay In Trees (CODIT) | Holes are commonly made in trees for injections, and for tapping maple sap. The sections here are from the same maple tree. Paraformaldehyde was added to the hole in the left section, but not to the control section on the right. This shows how chemicals may reduce a tree's ability to compartmentalize, so that decay develops rapidly. | |
| 1408061 | tree injections | When injecting or implanting substances keep the wound as small and shallow as possible. Treatments can be beneficial when properly applied. | |
| 1408064 | tree injections | Never make deep wounds or apply high pressure, | |
| 1408066 | tree implants | large holes created in injections or implants may create cankered areas and may keep the wounds from closing. | |
| 1408067 | tree implants | Follow the same careful procedure with implants. | |
| 1408068 | tree implants | When implants are first inserted, they cause very little damage to healthy trees. The story changes, however, as the injury is repeated year after year. | |
| 1408070 | cabling | Cables and braces can be beneficial if properly used. Do not anchor hardware in decayed wood, which fell away after the sample was cut. Only new wood that formed around the hardware remained sound. | |
| 1408071 | bracing | The same thing happened here. Sound new wood formed around the rod. Try to keep the tree healthy after bracing. | |
| 1408072 | bracing | Don't use sharp-edged washers; they cut into the tree and obstruct closure. | |
| 1408073 | cabling | Avoid cables angles that will cause screws to move, thus inhibiting firm closure. | |
| 1408076 | root problems | Other trees look safe, but have a weak root system. Always check for root decay when making a hazard tree inspection. | |
| 1408077 | decay | Fungus fruit bodies on old branch cuts are reliable indicators of internal decay. | |
| 1408078 | risk tree | You can also use electrical methods to detect decay and determine the relative vitality of trees. | |
| 1409002 | Compartmentalization Of Decay In Trees (CODIT) | The sawyer on the left is Dr. George Hepting, a pioneer researcher on tree decay. He observed compartmentalization of decay in trees in 1935. Dissecting trees with a crosscut saw was extremely difficult. Until 1959 our view of tree decay was obtained mainly from crosscut sections. | |
| 1409010 | Compartmentalization Of Decay In Trees (CODIT) | Hollows result when microorganisms digest the wood that was present at the time of wounding. | |
| 1409011 | Compartmentalization Of Decay In Trees (CODIT) | Hollows are found in trees that have heartwood | |
| 1409012 | Compartmentalization Of Decay In Trees (CODIT) | Hollows are found in trees that have heartwood | |
| 1409013 | Compartmentalization Of Decay In Trees (CODIT) | Hollows are found in trees that have heartwood | |
| 1409014 | Compartmentalization Of Decay In Trees (CODIT) | The same patterns of compartmentalization occur in roots. | |
| 1409015 | Compartmentalization Of Decay In Trees (CODIT) | Hollows do not always develop in the center, as evidenced in this tropical hardwood. | |
| 1409016 | Compartmentalization Of Decay In Trees (CODIT) | Trees compartmentalize injured and infected wood. To aid in understanding compartmentalization, we develop a model called CODIT, and acronym for Compartmentalization Of Decay In Trees. | |
| 1409017 | Compartmentalization Of Decay In Trees (CODIT) | The CODIT model has two parts. Part I has three walls: no. 1 resists vertical spread, no. 2 resists inward spread, and no. 3 resists lateral spread. Part II has one wall, no. 4 which separates wood present at the time of injury and infection from new wood. | |
| 1409018 | Compartmentalization Of Decay In Trees (CODIT) | CODIT is a model that applies to both non-heartwood and heartwood-forming trees | |
| 1409019 | Compartmentalization Of Decay In Trees (CODIT) | CODIT is a model that applies to both non-heartwood and heartwood-forming trees | |
| 1409020 | Compartmentalization Of Decay In Trees (CODIT) | This white oak had five basal wounds. The triangular-shaped discolored and decayed wood was formed by walls 2 and 3 which resisted spread, and wall 4 which separated infected wood from healthy wood. | |
| 1409021 | Compartmentalization Of Decay In Trees (CODIT) | Decay was less advanced in this western hemlock. | |
| 1409022 | Compartmentalization Of Decay In Trees (CODIT) | The green arrows point to wall no. 1 in this red maple. In an abstract sense, each growth ring is a new tree and each tree used the same mechanisms to resist the spread of decay. | |
| 1409024 | Compartmentalization Of Decay In Trees (CODIT) | Wall 4 extended entirely around the trunk of this sweetgum tree, a common, but not inevitable, occurrance. | |
| 1409025 | Compartmentalization Of Decay In Trees (CODIT) | In this birch tree, vertical arrows show wall no. 1, while horizontal arrows point to wall no. 4. | |
| 1409026 | Compartmentalization Of Decay In Trees (CODIT) | This slice of western hemlock was taken from the top of a wounded area. The red arrows shoe wall 4 within the growth rings. Points A and B show where wall 4 ends. | |
| 1409027 | Compartmentalization Of Decay In Trees (CODIT) | Wall 4 also forms after wood is infected. This elm had Dutch elm disease; the red arrows show where recent infections were walled off. | |
| 1409028 | Compartmentalization Of Decay In Trees (CODIT) | In response to a wound, this Norway spruce developed a wall 4, indicated by the red arrows, within the growth ring. The green arrows show how far the cells that produced resin extended. | |
| 1409029 | Compartmentalization Of Decay In Trees (CODIT) | Wall 4 is a model representation of a barrier zone, which is composed of strong protective tissue. This is the barrier zone from a spruce sample. | |
| 1409030 | Compartmentalization Of Decay In Trees (CODIT) | Though strong in one sense, the barrier zone is structurally weak and may pull apart, as it did in this white pine. | |
| 1409032 | Compartmentalization Of Decay In Trees (CODIT) | Trees form barrier zones around hardware. | |
| 1409033 | Compartmentalization Of Decay In Trees (CODIT) | After a tree is wounded, a wall 4 forms, as it did in this oak. Radial shakes often develop at the edges of the wound, where the pen and pencil are pointing. When pressure occurs due to heat, cold or felling, shakes may split outward. These splits are called frost cracks. | |
| 1409034 | Compartmentalization Of Decay In Trees (CODIT) | In this oak, the red arrows show the limits of an old wound. An open crack formed where callus first closed the injury. The green arrows point to radial shakes that split outward, while the blue arrows show ring shakes associated with other wounds. The purple arrows point to internal radial shakes. | |
| 1409035 | Compartmentalization Of Decay In Trees (CODIT) | This black walnut was wounded at the green arrows when it was 1 inch in diameter. At the red arrows the calus infoll cut into the trunk and caused an internal crack. | |
| 1409036 | Compartmentalization Of Decay In Trees (CODIT) | Multiple cracks form when many radial shakes associated with old wound split outward, as in this post oak. The cracks start at the circular barrier zone. | |
| 1409037 | Compartmentalization Of Decay In Trees (CODIT) | When decay and cracks combine, as they did in this black locust, wall 2 is the tree's only defense against the spread of decay. | |
| 1409038 | Compartmentalization Of Decay In Trees (CODIT) | A decayed basal sprout on this oak was a weak spot from which a crack spread inward at the purple arrows and outward at the red arrows. "S" indicates sapwood, "H" is heartwood, and the dotted line shows the boundary between them. | |
| 1409039 | Compartmentalization Of Decay In Trees (CODIT) | This is a typical cracking pattern. The purple arrows point to where callus closed the wound. | |
| 1409040 | Compartmentalization Of Decay In Trees (CODIT) | In response to insect wounds, this maple formed wall 4. Radial cracks developed later at the blue arrows. | |
| 1409041 | Compartmentalization Of Decay In Trees (CODIT) | Wall 4 in this eucalypt separated to form a ring shake. Felling caused a radial crack at the 6 o'clock position. | |
| 1409043 | tree anatomy | For proper pruning, start with identifying the branch bark ridge. Instead of cutting behind it or leaving a stub, cut along the red line. | |
| 1409045 | Compartmentalization Of Decay In Trees (CODIT) | Decay is essential for branch shedding. If decay surmounts the tree's natural chemical boundary, it will be walled off within the stub. | |
| 1409046 | flush cut | Flush cuts wound the trunk, which responds by forming wall 4. These walls often split. Microorganisms easily enter a trunk wound. Samples from an oak tree show that callus formed after it was wounded, an indication that decay did not develop. | |
| 1409048 | flush cut | Decay developed above and below the 13-year-old flush cut on this black walnut. | |
| 1409049 | Compartmentalization Of Decay In Trees (CODIT) | The leader on this beech was killed, and a branch became a new leader. Decay developed to the width fo the old leader and spread only downward. | |
| 1409052 | Compartmentalization Of Decay In Trees (CODIT) | Wound B in this maple was well compartmentalized. Wound A weakened at wall 2, because its inner edge was too close to the central column of discolored wood. | |
| 1409053 | Compartmentalization Of Decay In Trees (CODIT) | The same drill patterns appear in this oak, showing that heartwood compartmentalizes injured and infected wood. | |
| 1409054 | Compartmentalization Of Decay In Trees (CODIT) | Decay spread to the center of the beech at left. Before it was wounded, this tree was healthy from bark to pith, while the beech on the right already had a central column of altered wood. The drill wounds reached the center of both trees, but discolored and decayed wood associated with wounds did not penetrate the central column of the altered tree. | |
| 1409056 | Compartmentalization Of Decay In Trees (CODIT) | Again, the drill holes on this aspen penetrated to the red markes, yet discolored wood stopped at the arrows. | |
| 1409058 | Compartmentalization Of Decay In Trees (CODIT) | An example of this phenomenon is seen here, where decayed wood associated with the dead branch B did not spread into A or outward into C. | |
| 1409059 | Compartmentalization Of Decay In Trees (CODIT) | The heartwood is separate from the column of decayed wood on this sample, proving that microorganisms do not grow at will in trees. | |
| 1409061 | termites | Termites quickly invade wound-altered eucalypt wood. | |
| 1409064 | fire | In a white oak severely wounded by fire, heartwood formation comes to a standstill. Wounds stop hearwood from forming, while they initiate the formation of discolored wood. | |
| 1407074 | decay | brown cubical rot | |
| 1408062 | tree implants | Wounds close rapidly on fast-growing trees. Try not to make new wounds every year, or inflict them directly above or below older wounds. | |
| 1408063 | tree implants | Don't use high doses of chemicals. Small openings can cause large problems when phytotxic chemicals are used. | |
| 1408041 | Compartmentalization Of Decay In Trees (CODIT) | These sections came from a maple tree that was wounded experimentally. A wide variety of decay resulted, but all wounds showed the same type of thick callus ring. Again, callus is associated with the growth rate of the tree, not with the decay process. | |
| 1408053 | Compartmentalization Of Decay In Trees (CODIT) | We found many decay-causing fungi in tissue taken from treated and control wounds. If a client insists on using wound dressing, apply a very thin coat but only after you've compelted all the other procedures for maintaining a healthy tree. | |
| 1408056 | Compartmentalization Of Decay In Trees (CODIT) | When healthy wood is wounded, the tree walls off the injured areas. | |
| 1408057 | Compartmentalization Of Decay In Trees (CODIT) | When new wounds are added to wood that is already discolored and decayed from older injuries, much larger columns of infected wood will result. | |
| 1408058 | Compartmentalization Of Decay In Trees (CODIT) | These two maples received similar wounds at the same time. The one on the left shows little injury, but the one on the right sustained considerable damage. | |
| 1408059 | Compartmentalization Of Decay In Trees (CODIT) | Trees can wall off wounds effectively, but as damage accumulates over time, internal columns of infected wood begin to merge. This happens even with small wounds, | |
| 1408060 | Compartmentalization Of Decay In Trees (CODIT) | wounds inflicted in the tough root flair area. | |
| 1408047 | root sprouts | Prune basal sprouts as soon as you idnetify the desired dominant stems. Choose those that grow lowest on the old stump. Don't worry that decay may spread from a cut sprout or into a growing dominant sprout; it won't happen. | |
| 1408049 | flush cut | Fruit bodies of fungi often burst through wound dressings. This is a sure sign of decay, which can be stimulated by too much dressing. | |
| 1408050 | flush cut | This same tree had been cut in many places. Harsh flush-cuts and heavy coats of dressing will indeed cause the tree, as well as the people and property around it, some real problems. | |
| 1408051 | Compartmentalization Of Decay In Trees (CODIT) | We conducted research on wound dressings on hundreds of trees. After dissecting them, we found no difference between treated and control trees. These samples from the same white oak show no difference in callus formation. | |
| 1409067 | Compartmentalization Of Decay In Trees (CODIT) | Holes have helped researchers select individuals within a species that compartmentalize rapidly and effectively. All trees in Populus species, clone 42, were strong compartmentalizers, while all trees in clone 49 were not. It appears that the capacity to compartmentalize is under strong genetic control. | |
| 1409068 | annosum root disease | Heterobasidion annosum | CODIT is also applicable to root rots. A tree either rapidly stops the spread of infection, as shown in this pine infected by Fomes annosus, or it does not, letting the infection girdle and kill the root or butt. A cross-section was cut near the top of the dead area.... |
| 1409069 | Compartmentalization Of Decay In Trees (CODIT) | the fungus was walled off in the wood after being stopped in the bark. | |
| 1409071 | Compartmentalization Of Decay In Trees (CODIT) | In this spruce sample, the pencil indicates the limites of the dead bark. Fungi did not spread into new wood that formed after the infected wood was contained. | |
| 1409074 | Compartmentalization Of Decay In Trees (CODIT) | The bottoms of roots usually decay first and then connect with the wood between them at the tree butt. Decay will then be most advanced between the roots, as in this balsam fir. Trees with decay at this junction often split above the roots. | |
| 1408043 | crown reduction (pruning) | When removing a leader, slant the cut gently as shown on the left' a flat cut invited rapid decay development. | |
| 1408044 | crown reduction (pruning) | On the other hand, a severely slanted cut also encourages the spread of decay upward and downward. | |
| 1408021 | human caused injury | This oak was severely wounded when it was small. A crack later formed over the callus closure. Lawn mowers cause many injuries that later become cracks. Injured roots or roots killed during planting may also lead to cracks five or even 10 years later. | |
| 1408022 | flush cut | Cracks also start above flush-cut branches. One has started here at the pencil point on this maple which was flush-cut two years ago. | |
| 1408024 | pruning (general) | This is the right way to cut a large living branches. | |
| 1408025 | pruning (general) | Every branch has a thick bark ridge separating it from the main stem. Never cut behind the branch bark ridge. Never leave a stub, as shown here. Always cut as close as possible to the outer edge fo the branch bark ridge, as indicated by the red line. | |
| 1408026 | pruning (general) | The inner side of the sample shows the hard inner wood of the branch bark ridge. If you cut behind the ridge at the arrow you'll injure the main stem. Cut the branch, not the trunk, by following the red line. | |
| 1408027 | tree anatomy | You can easily locate the branch bark ridge on most trees | |
| 1408028 | tree anatomy | branch bark ridge on a small branch | |
| 1408029 | pruning (general) | Here is a proper cut on a small oak branch | |
| 1408030 | pruning (general) | Callus will ring proper cut on a small oak branch | |
| 1408032 | deadwood and snags | As branches wane and die, they are invaded by beneficial decay-causing fungi. These organisms spread to the base of the branch and branch collar, but rarely go beyond this point. | |
| 1408034 | deadwood and snags | According to nature's design, the branch is then shed. | |
| 1407053 | Armillaria root rots | Armillaria spp. | This is shoestring root rot. Named for the black bands that the fungus produces under dead bark, shoestring root rot often attacks weakened trees. Keep your trees healthy and vigorous through a well designed program of tree care. |
| 1407057 | root lifting, soil heaving, and windthrow | or changing the grade and moisture content of sites can cause major problems for trees. Consider the consequences before the work begins. | |
| 1407061 | wood decay | Wood products are sometimes invaded by fungi, though these organisms are different from those that attack living trees. Keep wood products dry and protect them with preservatives to discourage fungi. | |
| 1407042 | bracing | The same advice goes for inserting hardware to strengthen branches and trunks, | |
| 1407044 | Compartmentalization Of Decay In Trees (CODIT) | Trees produce a wall around injured and infected wood. You should never disturb this natural barrier. Injuries form an indelible record of a tree's life: a hollow will be equal in diameter to the diameter of the tree when it was injured. | |
| 1407049 | pruning (general) | Never prune where this saw is poised, behind the bark ridge. Cut in front of the ridge, as indicated by the red line. Never prune when the leaves are forming. As mentioned earlier, don't paint wounds except for cosmetic reasons; then use a thin coat of a commercial dessing, never a house paint | |
| 1407026 | tree anatomy | Intersection of tracheids with ray cells in the secondary xylem; Though they shed many outer parts, trees retain their wood, both healthy and decayed, in a highly ordered fashion. Viewed thorugh a microscope, this stained section of woody tissue reveals the order... | |
| 1407027 | tree anatomy | cross-section through xylem | |
| 1407028 | tree anatomy | This is a magnified section of American elm. | |
| 1407029 | Compartmentalization Of Decay In Trees (CODIT) | These microscopic units in woody tissue can be likened to rooms or compartments, which a tree can close off it they become injured or infected; illustrating walls 2, 3, and 4 | |
| 1407031 | fire | Throughout the ages, many trees have been wounded by fire, both natural and man-caused. | |
| 1407036 | ribbed crack | Many problems can be traced to wounds. The split seam in this piece of oak is called a frost crack, but the trouble actually began with an injury that occurred when the tree was one inch in diameter. As callus formed around the wound, a seam developed and later split. The tree may have been injured by a lawnmower or some type of equipment. If people knew the consequences of their actions, | |
| 1407040 | tree anatomy | The gum secreted by this peach tree is a natural dressing. All trees have similar self-healing mechanisms. | |
| 1408003 | tree grate | poor soils, severe wounding, | |
| 1408008 | Compartmentalization Of Decay In Trees (CODIT) | Cavities in trees start with wounds and dead branches or leaders. A cavity's diameter will be the same as that of the tree when it was wounded or when the branch or leader died. The leader on this birch tree died when the tree was the diameter of the cavity. | |
| 1408009 | decay | From another view you can see the dead leader beside the sound new leader. When filling cavities, do no injure the callus or break the band of hard wood around the decayed area. | |
| 1408013 | wetwood | Use metal tubes to drain wetwood fluids. This keeps wetwood fluids from spreading over the bark. | |
| 1408014 | Compartmentalization Of Decay In Trees (CODIT) | Wounds spell trouble for trees. Do everyhting you can to prevent them. Trees are able, however, to wall off wounds. | |
| 0488023 | gypsy moth | Lymantria dispar | forest types susceptible and potentially susceptible to attacks |
| 1396103 | eastern redcedar | Juniperus virginiana | male cones |
| 1396100 | eastern redcedar | Juniperus virginiana | female berries |
| 1396154 | black walnut | Juglans nigra | walnut storage in nursery |
| 1398045 | sycamore lace bug | Corythucha ciliata | |
| 1395001 | felling | ||
| 1395002 | felling | ||
| 1395061 | skidding | Skidding with small tractor | |
| 1395051 | chipping | Hickory chipping plant. 1962. | |
| 1395025 | transport | Log truck | |
| 1395017 | dry kilns | ||
| 1395022 | transport | Log truck | |
| 1395005 | loading | ||
| 1396184 | ectomycorrhizae | mycorrhizal fungi in circles around white spruce | |
| 1396168 | woodpeckers | sapsucker caused ring shakes | |
| 1396177 | ectomycorrhizae | Pisolithus tinctorius | ectomycorrhizal short roots from machine innoculated plots |
| 1396178 | ectomycorrhizae | Pisolithus tinctorius | ectomycorrhizal short roots from machine innoculated plots |
| 1396179 | ectomycorrhizae | Pisolithus tinctorius | ectomycorrhizal short roots |
| 1396176 | larch bolete | Suillus grevillei | mycorrhizal |
| 1396185 | Hebeloma mushroom | Hebeloma spp. | mycorrhizal |
| 1396158 | cedar-apple rust | Gymnosporangium juniperi-virginianae | |
| 1396128 | locust leafminer | Odontota dorsalis | |
| 1396129 | hackberry nipple gall parasitoid | Eurytoma semivenae | |
| 1396130 | hackberry nipple gall parasitoid | Eurytoma semivenae | |
| 1396131 | spruce spider mite | Oligonychus ununguis | |
| 1396132 | sapstreak disease of sugar maple | Ceratocystis coerulescens | |
| 1396149 | Nectria canker | Nectria spp. | |
| 1396151 | beech bark disease | Nectria coccinea | |
| 1396145 | Eutypella canker | Eutypella parasitica | showing yearly progression of canker |
| 1396146 | chestnut blight or canker | Cryphonectria parasitica | dead tree, picture taken 1943 |
| 1396101 | log deck | ||
| 1396102 | log deck | ||
| 1396105 | twolined chestnut borer | Agrilus bilineatus | |
| 1396106 | elm spanworm | Ennomos subsignaria | |
| 1396107 | large aspen tortrix | Choristoneura conflictana | |
| 1396108 | larger pine shoot beetle | Tomicus piniperda | typical bicolored dust associated with this species |
| 1396110 | larger pine shoot beetle | Tomicus piniperda | bluestain associated with T. piniperda attack |
| 1396121 | walnut shoot moth | Acrobasis demotella | |
| 1396122 | walnut shoot moth | Acrobasis demotella | frass |
| 1396115 | red turpentine beetle | Dendroctonus valens | |
| 1396112 | larger pine shoot beetle | Tomicus piniperda | cast shoots caused by T. piniperda maturation feeding |
| 1396079 | pales weevil | Hylobius pales | gall close-up |
| 1396082 | horned oak gall | Callirhytis cornigera | |
| 1396087 | post oak grasshopper | Dendrotettix quercus | |
| 1396089 | northern pine sphinx | Lapara bombycoides | |
| 1396084 | mourning cloak butterfly | Nymphalis antiopa | |
| 1396094 | spring cankerworm | Paleacrita vernata | |
| 1396097 | mugo pine | Pinus mugo | |
| 1396028 | yellownecked caterpillar | Datana ministra | |
| 1396029 | orangestriped oakworm | Anisota senatoria | |
| 1396023 | variable oakleaf caterpillar | Lochmaeus manteo | |
| 1396024 | variable oakleaf caterpillar | Lochmaeus manteo | |
| 1396025 | variable oakleaf caterpillar | Lochmaeus manteo | |
| 1396026 | variable oakleaf caterpillar | Lochmaeus manteo | |
| 1396042 | eastern pine seedworm | Cydia toreuta | |
| 1396043 | gall midges | Asynapta spp. | |
| 1396059 | lacewings | ||
| 1396060 | lacewings | ||
| 1396053 | European spruce sawfly | Gilpinia hercyniae | |
| 1396047 | variable oakleaf caterpillar | Lochmaeus manteo | |
| 1396049 | shieldbacked pine seed bug | Tetyra bipunctata | |
| 1396062 | bagworm | Thyridopteryx ephemeraeformis | adult emerging from bag |
| 1396064 | European pine shoot moth | Rhyacionia buoliana | |
| 1396055 | yellowheaded spruce sawfly | Pikonema alaskensis | Chippewa National Forest |
| 1396066 | basswood thrips | Neohydatothrips tiliae | |
| 1396067 | gypsy moth | Lymantria dispar | |
| 1396069 | uglynest caterpillar | Archips cerasivorana | |
| 1396002 | spruce budworm | Choristoneura fumiferana | and pupa |
| 1396010 | bronze birch borer | Agrilus anxius | exit hole |
| 1396011 | bronze birch borer | Agrilus anxius | exit hole |
| 1396012 | bronze birch borer | Agrilus anxius | |
| 1396015 | Saratoga spittlebug | Aphrophora saratogensis | flagging damaged trees |
| 1396018 | Saratoga spittlebug | Aphrophora saratogensis |
