GLOSSARY OF TERMS USED THROUGHOUT THE TREE ID WEBSITE

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ALIEN:  Refers to the geographical origin of a species beyond the region considered.  For example, a species whose origin is from Europe or Asia would be considered an "alien" in North America.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

ALTERNATE BRANCHING:  A branching pattern where side branches, leaves, and leaf scars do not grow directly across from each other.  The more common branching pattern in the U.P.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

BARK LAYERS:  In elms, the bark forms distinct layers as the tree trunk grows outward.  If you break off a thick piece of bark and look at the cross-section, you will clearly see layers.  With American elm, the layers are white/cream and red/brown.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

BLUNT:  The opposite of sharp.   Usually refers to the shape of terminal bud.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

BRACT:  A leaf-like structure associated with flowers and fruits.   [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

BROAD-LEAFED:    Trees and shrubs with flat leaves are called "broad-leafed".   This is different from the conifers, which have needles or scales.  So, a "broad-leaved" tree is a non-conifer, which includes most of our species.   "Broad-leafed" trees are also called "deciduous" trees or "hardwoods".  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

BUDS:   Both leaves and flowers begin as buds.  Leaves form as either "terminal" buds at the ends of twigs or "lateral" buds along the sides of twigs.  Most buds have protective scales that enclose the leaf tissue.  Buds without scales are called "naked".    Flower buds form in various places and are often much larger than leaf buds.   [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

BUNDLES:  Members of pine family (not other evergreens!) have groups of needles held together at the base by a small papery wrap called a "fascicle."  In Michigan, white pine has five needles per bundle, and other pine species have two.  Tamarack and larch appear to have many needles in bundles, but they are really clusters of needles at the end of short stubby twig.

CATKINS:  A cluster of flowers that forms a long, skinny, caterpillar-like shape is called a "catkin".   Catkins are typical of aspens, willows, oaks, birches, butternuts, and walnuts.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

CHAMBERED PITH:  The "pith" is the inside core of a twig, the youngest wood.  In butternuts and walnuts, the pith is formed by a series of tiny chambers which can be seen if the twig is sliced open.    [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

CLONES:  Individuals that are genetically identical are called clones.  This is the result of reproduction without flowers and seeds.  Aspen is a great example of a tree species that occurs in clones.   [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

COMPOUND LEAVES:  A single leaf with numerous leaflets.  A leaf begins where the leaf stem connects to the wood tissue of the twig.  Sometimes, the leaf stem supports these leaflets that look like individuals leaves but the leaf stem is not woody.  Ashes, boxelder, and butternuts display this characteristic.  Double-compound is when each leaflet is also made up of secondary leaflets.  Honeylocust is the only U.P. tree that is double-compound.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

CONIFER:  A "conifer" can also be called an "evergreen" or "softwood" tree.  However, it is inaccurate to call all conifers "pines"!  There are only three native pine tree species in the U.P. (white, red & jack) and seven species of non-pine conifers (balsam fir, hemlock, cedar, black & spruce, tamarack, and yew).  True pines (genus Pinus) make up only 15% of the number of conifers in the U.P.    [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

CORDUROY ROAD:  Where roads crossed wetland, small diameter logs were placed across the road to support hay wagons and other traffic.  Cedar was often the log of choice due to its rot-resistant character.  Some of these old corduroy roads can still be found, decades after they were constructed.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

CROWN:  All the branches that hold the leaves are collectively called a "crown".  It's the "lollipop" portion of the tree.  Sometimes crown size and shape help identify a tree, as with balsam fir or basswood.   [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

DECIDUOUS:  Trees and shrubs that lose their leaves or needles in the fall are called "deciduous".   Leaves and needles that remain on the tree through the winter, are part of the way into winter, are called "persistent".  Except for tamarack, deciduous trees can also be called "broad-leafed" trees or "hardwoods".  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

FISSURED:   A bark characteristic describing grooves and ridges.  Usually the grooves (or fissures) or fairly deep.  Sometimes looks like cracks or splits.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

FLOWERS:  All trees have flowers but not all are showy.  Some flowers have both male and female parts.   Other flowers may be only male or only female.  Sometimes, male and female flowers occur on separate trees.  The female parts consist of ovaries, stigmas, and styles.  The male flowers consist of stamens and anthers.  Petals or petal-like parts, when they are present, are usually associated with flowers that have female parts.  Ovaries occur at the base of a flower and have a tube, called a style, with a sticky end, called a stigma.  It is sticky to help catch pollen grains.  Fertilized ovaries will grow into fruits.   The anthers produce pollen, usually at the end of thin stalk called the stamen.   [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

GENUS:  "Genus" is the next to the lowest level of plant classification.  The lowest level is "species".  All known living organisms are organized into a classification system.  This is part of the science called "taxonomy".    Scientists refer to living things by a combined "genus" and "species" name, using Latin terms.  For example, people are called "Homo sapiens".  A white pine would be called "Pinus strobus".   A scientist anywhere in the world can look up information about any living organism by knowing the Latin or scientific name.  The genus name is always capitalized.   The species name is usually not capitalized.  The plural form of "genus" is "genera".  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

EVERGREEN:  An "evergreen" can also be called a "conifer" or "softwood" tree.  However, it is inaccurate to call all conifers "pines"!  There are only three native pine tree species in the U.P. (white, red & jack) and seven species of non-pine conifers (balsam fir, hemlock, cedar, black & spruce, tamarack, and yew).  True pines (genus Pinus) make up only 15% of the number of conifers in the U.P.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

FLOODPLAIN:   The flat land along a stream or river that floods on a regular basis, sometimes every year.  The soils are often quite rich with new nutrients brought in by floodwater.  Trees that grow in floodplains must be adapted to saturated soils that occur on the site.  Floodplains are part of the "riparian" habitat, which is the general zone along lakes and rivers.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

FOLIAGE:  A word that means "leaves in general", such a a group of leaves or all the leaves on a branch.  Usually it's better to simply say leaves or needles, but in the case of cedar the "foliage" does not fit into one of those categories as people normally think about them.  Technically, however, leaves include needles and all other plant structures with the primary job of photosynthesis. However, we usually associate "leaves" with just hardwoods.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

FOREST TYPE:  An association of particular group of tree species, named for the dominant tree species.   From the Society of American Forester it is "a category of forest usually defined by its vegetation, particularly its dominant vegetation as based on a percentage cover of trees, ... "   [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

HARDWOOD:  Trees and shrubs with broad-leaves (not needles or scales) that drop in the fall are called "hardwoods".    Hardwood trees can also be called "broad-leafed" trees or "deciduous" trees.   [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

LATERAL:  A word referring to the "side of" something.  Lateral branches are those growing out of the sides of other branches.  Lateral veins would be those coming from the mid-vein of a leaf.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

LAYERING:  A reproductive method used by few tree species where roots sprout from live branches or trunks that have come into permanent contact with the soil.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

LEAF BASE:  The bottom of the leaf at the stem.  The angle at which the leaf base joins the stem is helpful in tree identification.  Sometimes the base is "flat", other times it may be angled away from the twig (most leaves), or back to the twig (i.e. cottonwood & basswood).  An "unequal leaf base" is when the two sides of the leaf base may not join with the leaf stem in the same place, as with American elm.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

LEAF SCAR:  The mark left on a twig after the leaf drops in the Fall.  Each leave scar has a particular pattern of "bundle scars", which is where the leaf vessels passed into the twig.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

LEAFLETS:  Compound leaves are composed of several "leaflets".  These leaflets look like individual leaves but are not.   The leaf starts where the woody twig tissue ends.  This is not always easy to see.  Ashes and boxelder are common U.P. trees that have compound leaves with leaflets.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

LENTICLES:  Small bumps or spots on twigs that serve and "breathing" holes for the twigs.   Often used as an identifying characteristic in tag alder and birches.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

LOBES:  Lobes are "fingers" or "peninsulas" that make an irregular leaf shape.   Maples and oaks are best known for their lobed characteristic.  The indentations between lobes are called "sinuses".   Margins can smooth or toothed.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

MARGINS:  The leaf "margin" refers to the edge of the leaf.  The edge may be toothed or smooth, lobed or entire, or of other sorts of descriptions.  "Serrated" refers to a pattern resembling that of a hand saw.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

MONOTYPIC:  A taxonomic classification containing a single genus and single species.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

MORPHOLOGY:  The study of structures in living things.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

NATIVE:  A species which developed and evolved in a particular area and was present prior to European settlement.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

NATURALIZED:  Species which are not native, have been introduced, and now widely reproduces in our area.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

NODE:   The "joint" or place on a twig where there is a slight swelling and leaves, flowers, or twigs originate.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location

OPPOSITE BRANCHING:  A branching pattern where side branches, leaves, and leaf scars grow from the stem directly across from each other.   For U.P. trees, that identifies either a maple or ash.  Many shrubs, however, also have opposite branching, such as dogwoods and viburnums.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

PALMATE:  A particular shape of leaf where the main leaf veins begin at the same place near the leaf stem.   Named after the shape of a hand with the fingers spread wide.  Maple is the classic example of "palmate-shaped" leaves.   [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

PITH:   The center or inside of a twig, branch, or stem is called the "pith".  The kind of wood in the pith is often different than the kind of wood around the outside.  In some species, the pith has some really weird properties.  It might be a different color, or be really soft, or even have chambers.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

PHOTOSYNTHESIS:   The chemical process that green plants use to produce sugars (and oxygen) from carbon dioxide and water, thereby capturing solar energy for use in other chemical processes and tissue building activities of the plant.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

CO2 + H20 -----------------> SUGAR (C6H1206) + O2

PHYSIOLOGY:  The study of functions and processes in living things.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

RACEME:   A particular arrangement of flowers that is long and narrow.  Short flower stems branch off of a single (usually) main stem.  A common flower arrangement in some of the cherries.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SAMARA:  A kind of fruit.   Thin "wings" are attached to the seed.  Maples have "helicopters", the most commonly known samara.  However, ashes and elms also have samaras.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SCALY: Evergreen "needles" that are flattened and overlapping are called "scaly."  They look sort of like scales on a fish.  Northern white cedar is the only evergreen with scaly "needles."

SHRUB: "A woody, perennial plant differing from a perennial herb in its persistent and woody stem, and less definitely from a tree in its lower stature [size] and the general absence of a well-defined stem" [Society of American Foresters, 1998].  The problem is that some species can grow as trees or shrubs depending on climate and site conditions.  Species we might usually consider a shrub can sometimes grow to tree size.   A good example is juneberry.  Usually a shrub, it can grow to heights of 50 feet and over a foot in diameter under the right conditions.   [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SILHOUETTE:   The outline of a tree as seen from a distance.  The overall form and shape of a tree.  Many tree species have easy to recognize silhouettes, such as American elm, balsam fir, white pine, and sugar maple.   [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SIMPLE LEAVES:  A single leave stem is the same as the midrib.  Most of our U.P. tree species have simple leaves.  The leaf margins, however, have a wide variety of shapes that help identify trees.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SINUSES:  Leaf sinuses are the area between lobes.  Maples and oaks are typical examples of trees with "lobes" and "sinuses".  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SOFTWOOD:   A "softwood" can also be called an "evergreen" or "conifer" tree.  However, it is inaccurate to call all conifers "pines"!  There are only three native pine tree species in the U.P. (white, red & jack) and seven species of non-pine conifers (balsam fir, hemlock, cedar, black & spruce, tamarack, and yew).  True pines (genus Pinus) make up only 15% of the number of conifers in the U.P.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SPECIES:  A "species" is generally accepted as a group of individuals that look the same and can breed with each other but not usually with individuals of another species.  "Species" is the the lowest level of plant classification.  This is part of the science called "taxonomy".   Scientists refer to living things by a combined "genus" and "species" name, using Latin terms.  For example, people are called "Homo sapiens".  A white pine would be called "Pinus strobus".  A scientist anywhere in the world can look up information about any living organism by knowing the Latin or scientific name.   The genus name is always capitalized.  The species name is usually not capitalized.  Incidentally, the word "specie" is incorrect.  "Species" is the correct singular and plural form of the word.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SPROUTS:  One of methods some trees use to reproduce is to sprout from dormant buds.  Usually these buds are located around the root collar, near the ground.  If the parent tree should weaken or die, these dormant buds will often grow into sprouts.  This is common with species such as oak and birch.  Sprouts which grow from dormant buds on the root system are called suckers.  This is typical of aspens.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SPUR BRANCH:  Stubby portion of tamarack and larch twig that support clusters of needles.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

STIPULES:  Bumps or growths at the bottom of a leaf stalk.  Sometimes leafy-looking.  Common in members of the rose family.  Also helps separate black willow from peachleaf willow.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

STOUT:  Twigs come in various thicknesses.  "Stout" twigs that tend to be rather thick or chunky.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SUCKERS:    One of methods some trees use to reproduce is to sprout from old root systems.  If the parent tree should weaken or die, these dormant buds will often grow into suckers.   This is typical of aspens.  If suckers grow from stumps or around the bottom of the trunk, they are called stump sprouts.  This is common with species such as oak and birch.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

SWEEP:  Refers to gradual bends in the trunk of a tree leaving the trunk less than straight.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

TANNIN:   A brown-colored chemical found in plants.  Tannin can be used to soften animal hides for use as leather.  Hemlock and oak bark was an important source of tannin during the settlement of the Lake States.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

TEMPERATE CLIMATE or ZONE:   There are a number of global climate descriptions, one of which is "temperate".  This climate is the one in U.P.  and extends across much of the USA.  Temperate forests are dominated by hardwood species, have warm summers, cold winters, and rainfalls in the 20-60 inch range.  On the north is the boreal zone, to the south is the subtropical zone.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

TIGHT:  A bark characteristic meaning firm, not peeling, not loose, not peeling.   "Tight" bark on older trees may become furrowed or split, but does not rub off or peel off easily.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

TOOTHED MARGINS:   Some trees have leaf margins with variously sized and shaped "teeth" that help identify the species.  "Single-toothed" means all teeth are about the same size and shape.  "Double-toothed" means a fewer number of larger teeth and many smaller teeth on them and sometimes in-between the larger teeth.  "Serrated" refers to a pattern resembling that of a hand saw.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

TREE:  It might seem silly, at first, to define a tree.  Everyone knows what a tree is . . . don't they?  The difference between and tree and shrub can be defined without difficulty.  A tree is "a woody perennial plant, typically large and with a well-defined stem or stems carrying a more or less definite crown --- note sometimes defined as attaining a minimum diameter of 5 inches and a minimum height of 15 feet at maturity, with no branches within 3 feet of the ground" [Society of American Foresters, 1998].  The problem is that some species can grow as trees or shrubs depending on climate and site conditions.  A good example is black cherry.  Throughout most of its range, it grows as a tree.  But put on a poor site or along the northern edge of its range and it grows as a shrub.  Species that are obviously trees further south will sometimes occur only as shrubs in the far north.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

UNDERSTORY:   Forest vegetation is usually arranged in "layers", from the ground to the top of the forest canopy.  The biggest trees are called dominants or codominants.  The next layers are shorter trees either pushing their way into the canopy or suppressed (sickly) by the shade.   Sapling trees and shrubs for the "understory".   Below the understory are the small plants, herbs, grasses, ferns, etc.  [To return to previous page, click your browser's BACK button then scroll through the page to your last location]

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This site created and maintained by Bill Cook, MSU Extension Forester for the Upper Peninsula of Michigan.   Editing and modification is ongoing.  Submit suggestions, questions, and corrections to cookwi@msu.edu or call 906-786-1575.