2016 Junior Envirothon Forest Trees & Shrubs Additional Information & Glossary Provided to Help Better Understand the Study Materials Silvicultural Regeneration Methods From: Wikipedia.org http://en.wikipedia.org/wiki/Silviculture Silvicultural regeneration methods combine both the harvest of the timber on the stand and re-establishment of the forest. The proper practice of sustainable forestry should mitigate the potential negative impacts, but all harvest methods will have some impacts on the land and residual stand. The practice of sustainable forestry limits the impacts such that the values of the forest are maintained in perpetuity. Following are some common methods: • Single-tree selection - The single-tree selection method is an uneven-aged regeneration method most suitable when shade tolerant species regeneration is desired. It is typical for older and diseased trees to be removed, thus thinning the stand and allowing for younger, healthy trees to grow. Single-tree selection can be very difficult to implement in dense or sensitive stands and residual stand damage can occur. This method is also disturbs the canopy layer the least out of all other methods. • Group selection - The group selection method is an uneven-aged regeneration method that can be used when mid-tolerant species regeneration is desired. The group selection method can still result in residual stand damage in dense stands, however directional falling can minimize the damage. Additionally, foresters can select across the range of diameter classes in the stand and maintain a mosaic of age and diameter classes. • Clearcutting - An even-aged regeneration method that can employ either natural or artificial regeneration. It involves the complete removal of the forest stand at one time.[12] Clearcutting can be biologically appropriate with species that typically regenerate from stand replacing fires or other major disturbances, such as lodgepole pine (Pinus contorta). Alternatively, clearcutting can change the dominating species on a stand with the introduction of non-native and invasive species as was shown at the Blodgett Experimental Forest near Georgetown California. Additionally, clearcutting can prolong slash decomposition, expose soil to erosion, impact visual appeal of a landscape and remove essential wildlife habitat. It is particularly useful in regeneration of tree species such as Douglas-fir (Pseudotsuga menziesii) which is shade intolerant. • Patch cut • Seed-tree - An even-aged regeneration method that retains widely spaced residual trees in order to provide uniform seed dispersal across a harvested area. In the seed-tree method, 2-12 seed trees per acre (5-30/ha) are left standing in order to regenerate the forest. They will be retained until regeneration has become established at which point they may be removed. It may not always be economically viable or biologically desirable to re-enter the stand to remove the remaining seed trees. Seed-tree cuts can also be viewed as a clearcut with natural regeneration and can also have all of the problems associated with clearcutting. This method is most suited for light-seeded species and those not prone to windthrow. • Shelterwood - An even-aged regeneration method that removes trees in a series of three harvests: 1) Preparatory cut; 2) Establishment cut; and 3) Removal cut. The method's objective is to establish new forest reproduction under the shelter of the retained trees. Unlike the seed-tree method, residual trees alter understory environmental conditions (i.e. sunlight, temperature, and moisture) that influence tree seedling growth. This method can also find a middle ground with the light ambiance by having less light accessible to competitors while still being able to provide enough light for tree regeneration.[13] • Coppicing - A regeneration method which depends on the sprouting of cut trees. Most hardwoods, the coast redwood, and certain pines naturally sprout from stumps and can be managed through coppicing. Coppicing is generally used to produce fuelwood, pulpwood, and other products dependent on small trees. A close relative of coppicing is pollarding. • In Compound coppicing or coppicing with standards, some trees of the highest quality trees are retained for multiple rotations in order to obtain larger trees for different purposes. • Variable retention - A harvesting and regeneration method which is a relatively new silvicultural system that retains forest structural elements (stumps, logs, snags, trees, understory spieces and undisturbed layers of forest floor) for at least one rotation in order to preserve environmental values associated with structurally complex forests. "Uneven-aged and even-aged methods differ in the scale and intensity of disturbance. Uneven-aged methods maintain a mix of tree sizes or ages within a habitat patch by periodically harvesting individual or small groups of trees, Even-aged methods harvest most or all of the overstory and create a fairly uniform habitat patch dominated by trees of the same age". Even-aged management systems have been the prime methods to use when studying the effects on birds. Layers in a Deciduous Forest Ground Layer – leaf litter, fallen branches, lichens, clubmosses, and true mosses Herb Layer – short plants like ferns and trillium Shrub Layer – shrubs like rhododendrons, azaleas, mountain laurels, and huckleberries Understory (sapling on small tree layer) – short tree species (dogwood, sassafras) and young trees Canopy (tree layer) – the tallest layer, 60 -100 feet high, with large oak, maple, beech, hickory, elm, basswood, linden, walnut, white pine, hemlock, cedar GLOSSARY achene A small, dry, indehiscent one-seeded fruit with a thin wall, as in the sunflower. adventive Not native to and/or not fully established in a new habitat or environment; locally or temporarily naturalized. alternate The arrangement of leaves along a stem where consecutive leaves alternate along different sides of the stem. Taken together, all of the leaves plus the stem lie in roughly the same geometric plane. In winter (after leaf drop for deciduous plants), the arrangement can be determined by looking at the leaf scars or buds on the dormant twigs. annual A plant that completes its entire life cycle in a single growing season. appressed Lying flat or pressed closely against something, as hairs on certain plant stems axil The area between a leaf and stem, where an axillary bud forms. The axillary bud can be a floral bud that becomes a flower, or a vegetative bud that may produce a lateral stem (or remain dormant). biennial A plant that normally requires two seasons to complete its life cycle, growing usually as a rosette in the first season and producing flowers and fruits and then dying in the second season. basal Located at or near the base of a plant stem, or at the base of any other plant part: bole Another term for the trunk of a tree bolting To flower or produce seeds prematurely or develop a flowering stem from a rosette. bract A leaf-like or scale-like plant part, usually small, sometimes showy or brightly colored, and located just below a flower, a flower stalk, or an inflorescence. bud The tightly wrapped structure that contains miniaturized forms of leaves and stems (vegetative bud) which may open at a later date or remain dormant forever, or flowers (floral bud) which open the following spring. bundle The grouping together of needles on a pine tree into a unified cluster, bound by a sheath (or fascicle) at the base, and attached at a single point to the twig. Individual species of pine trees are known by the number of needles in a bundle; for example, White Pine has five, Loblolly Pine has three, and Scotch Pine has two. bundle scar Any small mark left on the leaf scar from the vascular tissue, where the leaf was once attached to the stem cambium The growth layer of a woody plant. A meristem that gives rise to radial rows of cells in stem and root, increasing them in girth; commonly applied to the vascular cambium which produces wood and phloem and cork cambium, which produces bark GLOSSARY catkin Elongated cluster of single-sex flowers bearing scaly bracts and usually lacking petals conifer A plant that has cones, rather than fruits, as its method of dispersing seeds. Most conifers are needle-foliaged (evergreens such as the Spruces and Pines, or deciduous versions such as Larch) that have relatively large cones that spread open at maturity. However, others have a miniature berry-like cone (such as the Junipers) or a ball-like cone (such as Bald Cypress, a deciduous conifer) instead. cultivar Literally meaning a "cultivated variety", a cultivar is a form of a species that is propagated in mass production at nurseries, for sale as a landscape plant. Since most cultivars are clones, they are genetically identical to one another and display uniformity in all features, such as fall foliage color. deciduous A woody plant that drops its leaves in autumn. Most deciduous trees are broad-leaved, but several are "deciduous conifers" that have needles that drop in autumn. These include Eastern Larch and Bald Cypress. decurrent Having the leaf base extending down the stem below the insertion: defoliate To strip (a tree, bush, etc.) of leaves. dioecious Plants that have male flowers (or staminate flowers) on one plant, and female flowers (or pistillate flowers) on another plant. Therefore, a pollinating male plant bears no fruits or seeds, whereas a female plant may have fruits, if pollination and favorable environmental conditions occur. Examples of dioecious trees include Green Ash and Osage Orange. An advantage of dioecious trees is that seedless males can be selected and propagated. drupe A type of fruit having a single seed enclosed in a hard layer and covered with soft, often juicy flesh, as in cherries and peaches evergreen A woody plant that retains its leaves throughout the winter. These include broad-leaved evergreens (such as most rhododendrons and bayberries) and the more common needle evergreens (the pines, spruces, firs, and hemlocks).