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Home , Achene, Caryopsis, Pome

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Bio 320 - Ethnobotany April 16, 2015 Basic Plant Identification

I. Terminology and vocabulary It is important that we develop a good working knowledge of botanical terminology and vocabulary - thus we will spend today working on developing that knowledge.

This handout lists many terms that are necessary for identifying plants via a key. Don’t worry about memorizing them all, but you should feel comfortable with them. I am also giving you a copy of a key to families of plants native to Illinois. You should use that key to work some through the demonstration plants. Also be sure to examine the herbarium sheets for examples of interesting local plants. Handle the herbarium sheets very carefully. They are fragile.

A. Habit - extremely important in identifying plants grossly - trees, shrubs, herbs woody - trees - large, 1 main stem - shrubs - smaller, several main stems herbs - no well developed woody layer suffrutescent - only slightly woody, can be large - often upper parts of stems are herbaceous suffruticose - diminutive shrub - very woody

habit - stems acaulescent - no stem - a dandelion caulescent - have stem cespitose - in little tufts or dense clumps - used for small plants growing in turf

B. Plant parts Vegetative parts - roots, stems, leaves Reproductive parts - flowers and

Roots - often ignored in identifying plants, though can be important taproot - more or less fleshy, goes straight into ground - many dicots fibrous roots - bushy, thin fibers - all monocots

Stems can also be important in identification - herbaceous vs. woody nodes - where leave or branches are attached internodes - between nodes cauline - of the stem - leaves on stem

Shape - cross-sectional terete - round stem angled - ridged or angled stem winged stem - winged outgrowths on stem 2

Stolon - prostrate stem on ground, reproduces at node or tip, capable of vegetative reproduction - slender one is runner

Underground plant parts that are technically stems rhizomes - underground stolon, skinny, sprouts at nodes corm - fleshy stem - underground part has solid center - gladiolus bulb - a bud underground with fleshy scales, no solid center - onion tuber - underground stem with many buds or nodes - potato

Leaves DICOT LEAF AND PARTS

Rosaceae - have stipules Saxifragaceae - lack stipules

MONOCOT LEAF AND PARTS long blade attached to stem, sheath at base of leaf, surrounds stem, hold stem to leaf; ligule - upper surface of leaf where it attaches to sheath, not always present have petioles

Disposition of leaves Alternate - one leaf per node

3 opposite - 2 leaves at node whorled (verticillate) - 3 or more leaves at node

Fascicled - leaves in tight bundle, all seeming to come from one point - like pines

Basal leaves - from leaves at base of plant, nodes have elongated; also radical - leaves seeming to grow from root - dandelion cauline - on stem simple - petiole attaches to stem compound - leaf appears to be highly subdivided PINNATE AND PALMATE

bud at apex - simple leaf on stem axiallary bud - bud where petiole joins stem - axillary bud on almost all leaves, but not on leaflets

Shape of leaves – orbicular - round leaf elliptic - flattened circle, even at both ends - 2x longer than wide oval - same width both ends - less than 2x longer than wide ovate - egg shaped lanceolate - long narrow, lance shaped linear - long narrow leaves - parallel sides filiform - hair-like or thread like 4

spatulate - spoon shaped

Leaf bases cuneate - wedge shaped cordate - heart shaped, with petiole attached at notch

Leaf apex obtuse acute acuminate attenuate

Pubesence - plant hairs trichomes - hair-like or triangular projections from plant surface

Other surface terms glandular - protuberance or outgrowths that put out secretions glaucous - grayish blush or bloom like a grape papillate - has minute processes punctate - pitted, translucent glands scabrous - scaly trichomes sticking out of plant glabrous - lack hairs or trichomes

II. Flower terminology The business of flowers is reproduction generalized flowers - 2 outer sets of sterile parts, 2 inner sets of fertile parts

flower is homologous to vegetative branch - arose from leaves

outer sterile part - , collectively the calyx - may do photosynthesis, protect flower, like leaves in texture, protect bud - form outer covering of bud

next sterile part - petals - not like leaves in texture, usually not green, collectively called corolla - petalloid - petal like in appearance

both sepals and petals can be fused - so sepals joined together, petals joined together

perianth - calyx and corolla together - used when the two cannot be distinguised - sometimes sepals and petals are called tepals for perianth - not well differentiated

If only one set of sterile parts, they are always called sepals; sometimes whole perianth is missing

First fertile parts - - male - androecium

innermost fertile parts - pistils, female - 5

flowering plants always have enclosed - nonflowering plants don't Carpel is highly modified leaf - a simple pistil of one ovary Pistil may be made up of one carpel or several fused carpels

Flower shapes regular/ radially symmetrical/actinmorphic - mirror images irregular/bilaterally symmetrical/zygomorphic - only one mirror image - peas, mints

Plant sexuality monoecious - separate flowers for male and female both on one plant - corn dioecious - male and female plants are separate - separate sexes - gingko

Basic flower terms connate - like parts grow together to form one structure - petals fuse to form bell - morning glories adnate - unlike parts grow together - sometimes stamens adnate to petals and appear to start half way up petal - some inferior ovaries have arisen by petals and sepals becoming adnate around ovary - more or less expanded end of flower stalk (pedicel) that bears the organs of the flower; or the collected flowers of a head as in disk - enlargement of receptacle around pistil - an enlargement or elongation of floral axis below calyx hypogynous - all floral parts insert below ovary - superior ovary epigynous - all floral parts borne above ovary - inferior ovary perigynous - floral parts borne around ovary - often in hypanthium or floral tube

B. Inflorescence terms - more or less modified leaf that subtends flower or flower groups - bract can look like normal leaf bract can also look like petal - petalous - dogwoods have big white "petals" that are really petaloid - flowers in clusters involucre - whorl of bracts subtending flower - flowers in cluster or separate peduncle - stalk of cluster of flowers pedicel - stalk of individual flower 6 petiole - leaf stalk scape - leafless peduncle of acaulescent plant - may have leaf-like bracts sessile flower is inserted on axis with no stalk

Types of inflorescence 1. indeterminant - youngest flower at apex - in theory could produce flowers forever - some may by fruiting while apex still flowering include - racemes, panicle, spike, corymb, head, umbel, catkin

2. determinant - oldest flowers at apex - moving down younger flowers - cyme, scorpiod cyme raceme - simple indeterminant flower stalk - with single axis off rachis panicle - compound raceme spike - sessile flowers, often crowded - axis elongate corymb - raceme with lower pedicels longer than top, so looks flat topped - can have compound corymbs umbel - all branch from 1 point - can be compound head - dense sessile flower - no elongation catkin - spike-like inflorescence with reduced unisexual flowers - oaks, birches cyme - general term for determinant inflorescence - can be of any shape scorpiod cyme - has coiled shape - typical of Boraginaceae, forget-me-nots flowers can be solitary - don't have to be in inflorescence - can be terminal or axillary

D. types Defined by anatomy - flowers have ovaries that enclose ovules - if a reproductive structure has ovary tissue it is a fruit - are fruit - if it has ovary tissue and more than , it is a fruit - ovule develops into seed dehiscent - fruit splits open on its own - often has split on fruit - fruits are dry, not fleshy indehiscent - fruit won't split on its own - can be fleshy locule - chamber in a fruit 7 valve - segment of dehiscent fruit after it splits

Dehiscent - , , follicle - develops from one carpel, has 1 line of - milkweed capsule - dry dehiscent fruit from compound ovary - more than one carpel - poppy legume - dry, 1 celled, 1 carpellate fruit that splits down two sides - 2 valves - typical of

Indehiscent - , , pepo, , akene (), , , drupe - fleshy, 1 sided indehiscent fruit with stony endocarp - peach, cherry, avocado berry - fleshy fruit formed from compound ovary containing few to many - tomato, grape, orange

Pepo - from inferior ovary - outer wall of fruit becomes rather tough - cucumber, squash, pumpkin pome - calyx tube becomes fleshy along with ovary - typical of apple subfamily of achene - dry indehiscent single seeded fruit - seed attached to pericarp at one point - sunflower - pericarp is surrounding protective cover caryopsis - singled seeded dry fruit - seed attached to pericarp at all points - grasses samara - single seeded winged dry fruit - nut - single seeded dry fruit with hard outer covering