Leaf Identification Topic 2014A and 2014 D Amanda Trutsch

Characteristics of: Monocot Dicots Embryo with single cotyledon Flower parts in multiples of three Major leaf veins parallel Dicots Embryo with two cotyledons Flower parts in multiples of four or five Major leaf veins reticulated (net venation)

Monocot http://www.ipm.iastate.edu/images/plantpath/corn/grayleafspot/0093.8grayleafspot.gif http://www.emc.maricopa.edu/faculty/farabee/BIOBK/monocot_flower.gif http://www.birdhybrids.com/resources/cornSeed.jpg

Dicot http://gecko.gc.maricopa.edu/~lsola/Flower/hibisc.jpg http://web.vet.cornell.edu/ http://www.harcourtschool.com/glossary/science/images/gr6/dicot6.jpg

Types of Leaves Broadleaf Conifer Broad, flat leaf Also called hardwoods Many are decidious Ex: maple, oak, birch Conifer Needle-shaped or scale-like leaves Also called softwood Ex: White pine, juniper, yew

Conifer Broadleaf http://www.istockphoto.com http://ridge.icu.ac.jp/gen-ed/lower-plants-gifs/23f-conifer-parts.JPG

Broadleaves

Leaf Parts to Look At: (apex)

Characteristics to look for: Leaf arrangement Leaf composition Overall shape Leaf tip Leaf margin Leaf base

Leaf Arrangement on Stem Alternate Opposite Whorled Three or more leaves attached to a single node Two leaves attached to the same node One leaf attached to a node http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Leaf Composition Simple Compound A leaf with only one leaf blade area A leaf with more than one leaf blade area http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Types of Compound Leaves Pinnate Compound Palmate Compound Leaflets arranged along a central axis like a feather A leaf with multiple leaf blade areas where the leaflets are attached to a common point http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Types of Compound Leaves, cont. Bipinnate Compound Trifoliate A compound pinnate leaf. The leaflets of a pinnate leaf are themselves compound. Three leaflets. The leaflets of a trifoliate leaf appear to be attached to a single location but maybe a reduced pinnate compound leaf. http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Some Leaf Shapes: Ovate: egg-shaped, about twice as long as it is wide, with the widest part below the center Elliptical: a narrow oval with the widest part in the middle of the leaf Linear: very long and narrow, slightly wider at the lower half Obovate: egg-shaped, with the widest part of the leaf above the center Obcordate: heart-shaped leaf attached at the narrow end (the opposite of cordate) http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Leaf Margins Entire: not toothed or notched Doubly Serrate: forward-facing teeth that have smaller teeth Serrulate: margins with small forward-facing teeth Serrate: forward-facing teeth Crenate: rounded teeth perpendicular to the margin http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Leaf Margins, cont. Incised: cut by sharp, irregular incisions Dentate: teeth pointing perpendicular to the margin of the leaf Sinuate: with a strongly wavy margin Lobed: margins with rounded teeth nearly halfway to the midrib Undulate: margins wavy, up and down http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Leaf Tips Acuminate: Terminating into a long drawn out point. Acute: Tip with sides having an angle of less than 90 degrees. Truncate: Cut off flat at the tip, may sometimes be slightly indented. Obcordate: Heart-shaped tip. http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Leaf Tips, cont. Emarginate: With a small notch at the apex. Mucronate: Tipped with a short, sharp point. Obtuse: Sides with an angle greater than 90 degrees Rounded: Apex rounded. http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Leaf Bases Cuneate: narrow wedge shaped Auriculate: ear lobe like base Rounded: round base http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Leaf Bases, cont. Cordate: heart shaped Truncate: cut off at the base Oblique: unequal base sides http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Conifers

Needle Types Needles in bundles or clusters Two or more needles joined at base Ex. White pine, jack pine, larch http://www.isaontario.com/media/news_letter/spec_focus/JackPine.jpg http://www-saps.plantsci.cam.ac.uk/trees/images/leaves/28.jpg

Needle Types Needles in Singles Each needle growing singly on a twig Ex. Douglas fur, hemlock, blue spruce http://ridge.icu.ac.jp/gen-ed/lower-plants-gifs/23f-conifer-parts.JPG

Needle Types Overlapping scales Leaves shaped like overlapping plates (like fish scales) Ex. Juniper, cedar, cypress http://preservedgardens.com/images/pressed-foliage/Juniper.JPG http://www.buenavistatownship.org/Photos/Atlantic%20white%20cedar%20leaf.jpg