Leaf Identification

Topic 2014A and 2014 D

Amanda Trutsch

Characteristics of:

MonocotEmbryo with single

cotyledon Flower parts in

multiples of three Major leaf veins

parallel

DicotsEmbryo with two

cotyledons Flower parts in

multiples of four or five

Major leaf veins reticulated (net venation)

http://www.emc.maricopa.edu/faculty/farabee/BIOBK/monocot_flower.gifhttp://www.ipm.iastate.edu/images/plantpath/corn/grayleafspot/0093.8grayleafspot.gif

Monocot

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 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

Broadleaf Conifer

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

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

One leaf attached to a node Two leaves attached to the same node

Three or more leaves attached to a single 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 LeavesPinnate Compound Palmate

Compound

A leaf with multiple leaf blade areas where the leafletsare attached to a common point

Leaflets arranged along a central axis like a feather

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:

Linear:very long and narrow, slightly

wider at the lower half

Ovate:egg-shaped, about twice as long as it is wide, with the widest part below the center

Obcordate:heart-shaped leaf attachedat the narrow end (the opposite of cordate)

Elliptical:a narrow oval with the widest part in the middle of the leaf

Obovate:egg-shaped, with the widest part of the leaf above the center

http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Leaf Margins

Entire:not toothed or notched

Serrulate:margins with small forward-facing teeth

Serrate:forward-facing teeth

Doubly Serrate:forward-facing teeth that have smaller teeth

Crenate:rounded teeth perpendicular to the margin

http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Leaf Margins, cont.

Dentate:teeth pointing perpendicular to the margin of the leaf

Sinuate:with a strongly wavy margin

Incised:cut by sharp, irregular incisions

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 beslightly indented.

Obcordate:Heart-shaped tip.

http://users.scc.spokane.edu/PShaw/morph/tippick.htm

Leaf Tips, cont.

Mucronate:Tipped with a short, sharp point.

Obtuse:Sides with an angle greater than 90 degrees

Rounded:Apex rounded.

Emarginate:With a small notch at the apex.

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