Alders are trees that compose the genus Alnus in the birch family Betulaceae. The genus includes about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species extending into Central America, as well as the northern and southern Andes.
Fraxinus, commonly called ash, is a genus of plants in the olive and lilac family, Oleaceae, and comprises 45–65 species of usually medium-to-large trees, most of which are deciduous trees, although some subtropical species are evergreen trees. The genus is widespread throughout much of Europe, Asia, and North America.
Alnus glutinosa, the common alder, black alder, European alder, European black alder, or just alder, is a species of tree in the family Betulaceae, native to most of Europe, southwest Asia and northern Africa. It thrives in wet locations where its association with the bacterium Frankia alni enables it to grow in poor quality soils. It is a medium-sized, short-lived tree growing to a height of up to 30 metres (98 feet). It has short-stalked rounded leaves and separate male and female flowers in the form of catkins. The small, rounded fruits are cone-like and the seeds are dispersed by wind and water.
Alnus rubra, the red alder, is a deciduous broadleaf tree native to western North America.
Alnus incana, the grey alder, tag alder or speckled alder, is a species of multi-stemmed, shrubby tree in the birch family, with a wide range across the cooler parts of the Northern Hemisphere. Tolerant of wetter soils, it can slowly spread with runners and is a common sight in swamps and wetlands. It is easily distinguished by its small cones, speckled bark and broad leaves.
A plant canker is a small area of dead tissue, which grows slowly, often over years. Some cankers are of only minor consequence, but others are ultimately lethal and therefore can have major economic implications for agriculture and horticulture. Their causes include a wide range of organisms as fungi, bacteria, mycoplasmas and viruses. The majority of canker-causing organisms are bound to a unique host species or genus, but a few will attack other plants. Weather and animal damage can also cause stress to the plant resulting in cankers. Other causes of cankers is pruning when the bark is wet or using un-sterilized tools.
Diamond willow is a type of tree with wood that is transformed into diamond-shaped segments with alternating colors. Salix bebbiana, the most common, is a species of willow indigenous to Canada and the northern United States, from Alaska and Yukon south to California and Arizona and northeast to Newfoundland and New England. Among common names are beaked willow, long-beaked willow, gray willow, and Bebb's willow. This species is also called red willow by Native Americans according to The Arctic Prairies Appendix E by Ernest Tompson Seton.
In trees, heart rot is a fungal disease that causes the decay of wood at the center of the trunk and branches. Fungi enter the tree through wounds in the bark and decay the heartwood. The diseased heartwood softens, making trees structurally weaker and prone to breakage. Heart rot is a major factor in the economics of logging and the natural growth dynamic of many older forests. Heart rot is prevalent throughout the world affecting all hardwood trees and can be very difficult to prevent. A good indication of heart rot is the presence of mushrooms or fungus conks on the tree.
Fomitopsis pinicola, is a stem decay fungus common on softwood and hardwood trees. Its conk is known as the red-belted conk. The species is common throughout temperate Europe and Asia. It is a decay fungus that serves as a small-scale disturbance agent in coastal rainforest ecosystems. It influences stand structure and succession in temperate rainforests. It performs essential nutrient cycling functions in forests. As well as a key producer of brown rot residues that are stable soil components in coniferous forest ecosystems. It has been reported that mushrooms have significant antioxidant activity.
Cryptococcus gattii, formerly known as Cryptococcus neoformans var. gattii, is an encapsulated yeast found primarily in tropical and subtropical climates. Its teleomorph is Filobasidiella bacillispora, a filamentous fungus belonging to the class Tremellomycetes.
Silver leaf is a fungal disease of trees caused by the fungal plant pathogen Chondrostereum purpureum. It attacks most species of the rose family Rosaceae, particularly the genus Prunus. The disease is progressive and often fatal. The common name is taken from the progressive silvering of leaves on affected branches. It is spread by airborne spores landing on freshly exposed sapwood. For this reason cherries and plums are pruned in summer, when spores are least likely to be present and when disease is visible. Silver Leaf can also happen on poming fruits like apples and pears. Plums are especially vulnerable.
Erythricium salmonicolor is a species of fungus in the family Corticiaceae. Basidiocarps are effused, corticioid, smooth, and pinkish and grow on wood. The fungus is a commercially significant plant pathogen which has become a serious problem, especially in Brazil. Erythricium salmonicolor causes Pink Disease, most commonly in Citrus, although E. salmonicolor has a wide host range including rubber and cacao trees. Pink Disease causes branch and stem die-back due to canker formation. The cankers are recognizable by gum exudation and longitudinal splitting of the bark.
Phytophthora alni is an oomycete plant pathogen that causes lethal root and collar rot in alders. It is widespread across Europe and has recently been found in North America. This species is believed to have originated relatively recently.
Phellinus igniarius, commonly known as the willow bracket, fire sponge,false tinder polypore, or false tinder conk, is a fungus of the family Hymenochaetaceae. Like other members of the genus of Phellinus, it lives by saprotrophic nutrition, in which the lignin and cellulose of a host tree is degraded and is a cause of white rot.
Bridgeoporus is a fungal genus in the family Polyporaceae. A monotypic genus, it contains the single polypore species Bridgeoporus nobilissimus, first described to science in 1949. Commonly known both as the noble polypore and the fuzzy Sandozi, this fungus produces large fruit bodies that have been found to weigh up to 130 kilograms (290 lb). The upper surface of the fruit body has a fuzzy or fibrous texture that often supports the growth of algae, bryophytes, or vascular plants.
Cryptosporella is a genus of fungi in the family Gnomoniaceae. The genus was first circumscribed by Pier Andrea Saccardo in 1877. The genus contains 19 species.
Fomes fomentarius is a species of fungal plant pathogen found in Europe, Asia, Africa and North America. The species produces very large polypore fruit bodies which are shaped like a horse's hoof and vary in colour from a silvery grey to almost black, though they are normally brown. It grows on the side of various species of tree, which it infects through broken bark, causing rot. The species typically continues to live on trees long after they have died, changing from a parasite to a decomposer.
Alnus alnobetula is a common tree widespread across much of Europe, Asia, and North America. Many sources refer to it as Alnus viridis, the green alder, but botanically this is considered an illegitimate name synonymous with Alnus alnobetula subsp. fruticosa.
Heterobasidion occidentale is a tree root-rotting pathogenic fungus in the family Bondarzewiaceae. It is endemic in western North America west of the Rocky Mountains from Alaska to southern Mexico. While a natural agent of forest turnover, H. occidentale has become of increased concern due to forest management processes such as pre-commercial thinning, altered site density and species composition, and carbon sequestration. H. occidentale forms part of the genus that includes other species forming the important forest pest Heterobasidion annosumsensu lato that is spread across the Northern Hemisphere. H. occidentale is part of the S-type intersterility group differing from the other North American species, Heterobasidion irregulare.
Eriocampa ovata, known generally as the alder sawfly or woolly alder sawfly, is a species of common sawfly in the family Tenthredinidae. The larvae feed on the leaves of the common alder and the grey alder, sometimes causing defoliation.
