Complete Reproductive Structure Documentation

Lab 4: Complete Reproductive Structure Documentation

Objectives

By the end of this lab, you will:

• Identify all flower parts (sepals, petals, stamens, carpels)

• Write floral formulas using botanical notation

• Classify ovary positions (critical for plant identification!)

• Match flower features to their pollinators

• Classify fruit types

• Identify seed dispersal mechanisms

• Calculate reproductive success and investment

Background Information

Flower Structure - The Basics

Simple explanation: A flower is a plant's reproductive structure. It has four main parts arranged in circles (whorls) from outside to inside:

![Diagram: Cross-section of generalized flower showing all four whorls]

1. SEPALS (Calyx) - Outermost whorl

• What they are: Usually green, leaf-like protective covers

• Function: Protect the flower bud before it opens

• In desert plants: Often hairy or waxy to reduce water loss

• May be colorful and look like petals in some flowers

2. PETALS (Corolla) - Second whorl

• What they are: Usually colorful, showy parts

• Function: Attract pollinators (bees, birds, bats, etc.)

• Features: Colors, patterns, scents, nectar guides

• In Mohave County: Often UV-reflective patterns visible to insects
  
  
  

3. STAMENS (Androecium) - Third whorl - MALE parts

• What they are: Pollen-producing structures

• Parts:

  • Filament: Thin stalk (like a stem)

  • Anther: Pollen sac at tip (where pollen is made)

• Function: Produce and release pollen (male gametes)

4. CARPELS (Gynoecium/Pistil) - Center whorl - FEMALE parts

• What they are: Seed-producing structures

• Parts:

  • Stigma: Sticky top that catches pollen

  • Style: Tube connecting stigma to ovary

  • Ovary: Base containing ovules (future seeds)

• Function: Receive pollen, produce seeds, develop into fruit

Ovary Position - VERY IMPORTANT!

Why it matters: Ovary position is critical for plant identification and shows evolutionary relationships.

Three types:

1. Superior Ovary (Hypogynous)

• Position: Ovary sits ABOVE where other parts attach

• Looks like: Flower parts attach below the ovary

• Common in: Buttercups, mustards, legumes, most desert wildflowers

• Drawing: [Simple side-view showing ovary on top]

2. Inferior Ovary (Epigynous)

• Position: Ovary sits BELOW where other parts attach

• Looks like: Flower parts appear to grow from top of ovary

• Common in: Sunflower family, cactus, evening primrose

• Drawing: [Simple side-view showing ovary at bottom]

3. Intermediate/Half-Inferior (Perigynous)

• Position: Ovary partially embedded in cup-like structure

• Looks like: Parts attach around middle of ovary

• Common in: Roses, cherries, plums

• Drawing: [Simple side-view showing ovary half-embedded]

Pollination Syndromes

Simple explanation: Flowers evolve features that attract specific pollinators. You can predict pollinators by looking at flower traits!

Fruit Types -

What is a fruit? A mature ovary containing seeds. The ovary wall becomes the fruit wall.

Two main categories:

DRY FRUITS (wall dries out when mature)

• Dehiscent (splits open to release seeds)

  • Legume: bean pod (splits along 2 seams)

  • Capsule: poppy (opens by pores/slits)

  • Follicle: milkweed (splits along 1 seam)

• Indehiscent (doesn't split open)

  • Achene: sunflower "seed" (one seed, thin wall)

  • Nut: acorn (one seed, hard shell)

  • Grain: grass seed (seed fused to fruit wall)

  • Samara: maple "helicopter" (winged achene)

FLESHY FRUITS (wall stays soft/juicy)

• Berry: Tomato, grape (entire wall fleshy, multiple seeds)

• Drupe: Peach, cherry (outer fleshy, inner stony pit, one seed)

• Pome: Apple (fleshy tissue from receptacle, not ovary)

Seed Dispersal Mechanisms

How seeds travel away from parent plant:

1. Wind (Anemochory)

• Adaptations: Wings, plumes, small/light

• Examples: Dandelion, cottonwood, maple

• Distance: Can travel kilometers

2. Animals - External (Epizoochory)

• Adaptations: Hooks, barbs, sticky coatings

• Examples: Bur-sage, puncture vine, tick trefoil

• Distance: Wherever animal travels

3. Animals - Internal (Endozoochory)

• Adaptations: Fleshy, colorful, edible fruits

• Examples: Juniper berries, cactus fruits, wolfberry

• Distance: Wherever animal defecates

4. Water (Hydrochory)

• Adaptations: Buoyant, waterproof

• Examples: Coconut, sedges near water

• Distance: Along waterways

5. Mechanical/Explosive (Autochory)

• Adaptations: Spring-loaded pods, explosive dehiscence

• Examples: Lupine, violet, touch-me-not

• Distance: Usually <5 meters

6. Gravity (Barochory)

• Adaptations: Heavy, no special structures

• Examples: Acorns, walnuts

• Distance: Just falls down

Materials

• Pruning shears or scissors

• Plastic bags (ziplock, various sizes)

• Permanent markers for labeling

• Field notebook and pencil

• Camera

• Paper towels (to keep flowers moist)

• Metric ruler (mm markings)

• Digital scale

• Plant press

Mohave County Plant Selection Guide

Target: 8-10 flowering species for Part 1, 5 species with fruits for Part 2

Category 1: Easy Spring Wildflowers (Collect 3-4 species)

Desert Annuals:

• Desert marigold (Baileya multiradiata) - yellow, composite, easy to find

• Desert chicory (Rafinesquia neomexicana) - white, dandelion-like

• Lupine (Lupinus sparsiflorus) - purple/blue, pea-shaped

• Desert dandelion (Malacothrix glabrata) - yellow, composite

• Chia (Salvia columbariae) - purple, whorled spikes

• Scorpion weed (Phacelia spp.) - purple/blue, coiled clusters

• Desert paintbrush (Castilleja spp.) - red bracts (modified leaves)

Good for: Clear flower parts, easy dissection, diverse structures

Category 2: Shrubs & Perennials (Collect 2-3 species)

Common Mohave Shrubs:

• Brittlebush (Encelia farinosa) - yellow daisies, composite

• Chuparosa (Justicia californica) - red tubular, hummingbird-pollinated

• Desert willow (Chilopsis linearis) - pink/purple, orchid-like, showy

• Creosote bush (Larrea tridentata) - small yellow, 5 petals

• Apache plume (Fallugia paradoxa) - white, rose family, feathery fruits

Cacti (if blooming - be careful of spines!):

• Prickly pear (Opuntia spp.) - large, many petals and stamens

• Hedgehog cactus (Echinocereus spp.) - red/pink, showy

• Barrel cactus (Ferocactus spp.) - yellow/red, waxy

Good for: Variety in pollination syndromes, interesting ovary positions

Category 3: Trees (if available) (Collect 1-2 species)

Riparian/Wash Species:

• Fremont cottonwood (Populus fremontii) - catkins (clusters of tiny flowers)

• Desert willow (Chilopsis linearis) - showy pink flowers

• Catclaw acacia (Senegalia greggii) - yellow puffball clusters

Introduced/Landscape:

• Olive (Olea europaea) - small white flowers

• Mulberry (Morus spp.) - tiny, wind-pollinated

• Fruit trees (if in bloom) - showy, insect-pollinated

Good for: Tree flower structures, economic plants

Category 4: Grasses & Monocots (Collect 1 species)

Grasses (spring green-up):

• Any grass species - tiny flowers but instructive!

• Big galleta, Indian ricegrass, or lawn grasses

Other Monocots:

• Yucca (Yucca spp.) - large white bells (if blooming - spring)

• Desert lily (Hesperocallis undulata) - rare but spectacular if you find it!

• Mariposa lily (Calochortus spp.) - 3 petals, beautiful

Good for: Monocot characteristics (parts in 3s), comparison to eudicots

Category 5: Weeds & Opportunistic Species (Collect 1-2 species)

Common Weeds (disturbed areas, roadsides):

• Russian thistle/Tumbleweed (Salsola tragus) - tiny flowers

• Puncture vine (Tribulus terrestris) - yellow, 5 petals, spiny fruits

• London rocket (Sisymbrium irio) - yellow, mustard family, long seed pods

• Filaree (Erodium cicutarium) - pink/purple, stork's-bill fruits

• Pigweed (Amaranthus spp.) - tiny green flowers in spikes

Good for: Always available, diverse structures, interesting fruits

Part 1: Floral Structure Documentation

Overview: You'll systematically dissect 8-10 flower species, working from outside to inside, documenting each whorl of parts.

Step 1: Specimen Collection

Timing considerations:

Collect early in day:

• Flowers fully open (usually mid-morning)

• Plants well-hydrated

• Before extreme heat (Mohave County!)

Flower longevity:

• Long-lasting (collect days ahead): Cactus, brittlebush, penstemon, desert marigold

• Short-lived (collect same day): Evening primrose (fades by noon), sacred datura, morning glory

Collection protocol:

1. Choose healthy, fully open flowers

2. Collect 2-3 flowers per species (in case of damage)

3. Include some unopened buds (for comparison)

4. Cut with clean shears

5. Place immediately in labeled plastic bag

6. Add damp paper towel to bag

7. Keep cool (in cooler if hot day)

Label immediately:

• Species name (or number if unknown)

• Location

• Date and time

• Habitat notes

Step 2: Initial Whole-Flower Documentation

Do this BEFORE any dissection! You can't "undissect" a flower.

For each of your 8-10 species:

a. Basic Information

• Species name (scientific): _____

• Species name (common): _____

• Family (if known): _____

• Collection location: _____ (be specific: "rocky slope near Hualapai Peak" not just "Kingman")

• Collection date & time: _____

• Number of flowers examined: _____ (examine 2-3, use best for dissection)

• Reproductive stage: / Bud / Opening / Full bloom / Fading / Fruit developing

b. Whole-Flower Measurements

Use metric ruler, measure to nearest mm:

For radially symmetric (circular) flowers:

• Flower diameter (widest point across): _____ mm

• Flower length/depth (base to tip if 3D): _____ mm

For bilaterally symmetric flowers:

• Width (side to side): _____ mm

• Height (top to bottom): _____ mm

• Depth (front to back): _____ mm

Flower stalk:

• Pedicel length (stalk from stem to flower base): _____ mm

• Pedicel diameter: _____ mm

c. Visual Characteristics

Color pattern:

• Primary color(s): _____

• Secondary colors: _____

• Distribution: / Uniform (all one color) / Gradient (fades from one color to another) / Spots / Stripes/streaks / Bulls-eye pattern / Other: _____

Nectar guides (markings pointing to nectar/pollen):

• Present? / Yes / No

• If yes, describe: / UV-visible lines (use UV flashlight if available) / Color change at center (darker or lighter) / Spots leading inward / Textured ridges / Other: _____

Surface texture: / Smooth/glabrous / Waxy / Hairy/pubescent / Papillose (tiny bumps - feels rough) / Velvety / Other: _____

Overall shape: / Cup-shaped (open bowl) / Bell-shaped (hanging bell) / Tubular (long narrow tube) / Flat/open (daisy-like) / Irregular (orchid-like, snapdragon-like) / Spherical (globe-shaped) / Other: _____

Symmetry (IMPORTANT for classification): / Radial (actinomorphic) - can be divided into equal halves multiple ways, like a pie / Bilateral (zygomorphic) - can only be divided into mirror halves one way, like a face / Asymmetric (no symmetry - rare)

![Diagram showing examples of radial vs. bilateral symmetry]

d. Scent Assessment

Best time to check: Fresh flowers in morning

Scent present? / Yes / No

If yes:

• Intensity: / None (had to crush to smell) / Faint (need to get close) / Moderate (noticeable when near) / Strong (fills the air) / Overpowering (very intense)

• Quality (describe in your own words, but consider): / Sweet (like honey, vanilla) / Spicy (like cloves, cinnamon) / Fruity (like lemon, apple, peach) / Floral (rose-like, jasmine-like) / Musty/fermenting (yeasty, beer-like) / Unpleasant (foul, rotting - fly-pollinated!) / Other: _____

• Time of strongest scent: / Morning/day / Evening / Night (moth/bat flowers!) / Constant (all day)

Mohave County note: Many night-blooming flowers (sacred datura, evening primrose, some cacti) release scent at dusk!

e. Photography - Intact Flower

Take multiple photos BEFORE dissecting:

Required shots:

1. Face-on view (looking directly into flower)

   • Shows petal arrangement

   • Shows center (stamens/stigma)

   • 2-3 shots at different exposures

2. Side profile

   • Shows ovary position (critical!)

   • Shows flower shape

   • Shows how parts attach

3. Back view

   • Shows calyx (sepals)

   • Shows pedicel attachment

   • May show ovary if inferior

4. Close-up of center

   • Shows stigma clearly

   • Shows anther arrangement

   • Use macro mode if available

Photography tips:

• Include scale bar (ruler) in ALL images

• Use appropriate background:

  • White for dark flowers

  • Black/dark for light flowers

• Natural light is best (avoid flash if possible)

• Get close - fill the frame

• Keep camera level with flower

Step 3: Systematic Dissection

CRITICAL PRINCIPLE: Work from outside to inside!

Remove parts in order: Sepals → Petals → Stamens → Carpels

Setup:

• Clear workspace

• White paper or poster board

• Tweezers, razor blade, ruler ready

• Camera ready (photograph each step)

a. SEPALS (Calyx) - First Whorl

Simple explanation: Sepals are the outermost protective layer, usually green, but can be colorful.

Procedure:

1. Carefully detach each sepal at its base using tweezers

   • Pull gently outward and twist slightly

   • Try not to tear

2. Arrange on white paper in natural position (as they appeared on flower)

   • Keep them in order (clock face pattern)

3. Count total sepals: _____

4. Fusion state (are they connected?): / Free (separate pieces - easy to remove individually) / Partially fused (joined at base, free at tips) / Completely fused (all grown together into tube)

5. If fused, measure:

   • Fused tube length: _____ mm (the connected part)

   • Free lobe length: _____ mm (the separated tips)

   • Tube diameter at opening: _____ mm

6. Individual sepal measurements (measure 2-3):

   • Length: _____ mm (base to tip)

   • Width: _____ mm (widest point)

   • Shape: / Linear (very narrow) / Lanceolate (lance-shaped) / Ovate (egg-shaped) / Round / Other: _____

7. Color: _____ (may be green, or colored like petals)

8. Texture: / Herbaceous (leaf-like, green) / Petaloid (petal-like, colorful) / Scarious (dry, papery, often brown) / Other: _____

9. Special features: / Spurs (backward-pointing projections) / Glands (nectar-producing spots) / Hairs/trichomes / None

Photograph arranged sepals with scale bar 

b. PETALS (Corolla) - Second Whorl

Simple explanation: Petals are usually the colorful, showy parts that attract pollinators.

Procedure:

1. Detach each petal at base with tweezers

   • Be gentle - petals are delicate!

   • May need to cut if fused

2. Arrange in natural position on paper (below sepals)

3. Count total petals: _____

4. Fusion state: / Free (separate petals) / Partially fused (joined at base into tube, free lobes) / Completely fused (all grown together)

5. If fused, measure:

   • Tube length: _____ mm

   • Lobe length: _____ mm (free tips)

   • Tube diameter at opening: _____ mm

   • Tube diameter at base: _____ mm

6. Individual petal measurements (measure 2-3):

   • Length: _____ mm (base to tip along midline)

   • Width at widest point: _____ mm

7. Petal shape: / Rounded / Oblong (rectangle-ish) / Linear (very narrow) / Spatulate (spoon-shaped - narrow base, wide tip) / Ovate (egg-shaped) / Other: _____

8. Apex (petal tip): / Entire (smooth edge) / Notched (shallow V-cut) / Fringed (many tiny cuts) / Pointed / Other: _____

9. Color gradients or patterns:

   • Describe any color changes from base to tip

   • Note spots, stripes, or other patterns

   • 
     

10. Check for nectar:

    • Nectar present? / Yes / No

    • Location: / Base of petal / Inside tube / Spur (backward projection) / Nectary disk (at flower base)

    • Amount: / None visible / Tiny droplet / Small pool / Abundant

11. Photograph arranged petals with scale

c. STAMENS (Androecium) - Third Whorl - MALE PARTS

Simple explanation: Stamens make pollen. Each stamen has a stalk (filament) and a pollen sac (anther).

Procedure:

1. Carefully remove each stamen

   • Grasp filament with tweezers

   • Pull gently from base

   • Try not to damage anthers

2. Arrange in order around edge of paper (below petals)

3. Count total stamens: _____

   • If numerous (>20), estimate count and describe: "Many stamens in multiple whorls"

4. Fusion state: / Free (all separate) / Filaments fused: / Monadelphous (all filaments fused into one group/tube) / Diadelphous (filaments in two groups) / Anthers fused (filaments free but anthers stuck together) / No fusion

5. Arrangement: / Single whorl (one ring) / Multiple whorls (2+ rings) / Spiral pattern / Clustered / Other: _____

Measure 3-5 representative stamens:

Additional stamen characteristics:

• Filament color: _____

• Anther color (before opening): _____

• Anther color (after pollen release): _____

Examine pollen:

1. Anther dehiscence (how anthers open): / Longitudinal (splits length-wise - most common) / Poricidal (opens by small pores at tip) / Valvular (opens by flaps) / Not yet dehisced (still closed)

2. Pollen characteristics:

   • Color: _____ (yellow, white, orange, purple, etc.)

   • Abundance: / Sparse (little pollen) / Moderate / Copious (lots of pollen!)

   • Texture: / Powdery (dusty, dry) / Sticky (clumps together) / Granular (grainy feel)

   • Shape (if visible with hand lens): / Round/spherical / Oval / Triangular / Other: _____

3. Stamen attachment:

   • Attached to: / Receptacle (flower base) / Corolla tube (on petals) / Other: _____

   • Position relative to stigma: / Same height / Shorter than stigma / Longer than stigma (anthers stick out)

4. Photograph:

   • Arranged stamens with scale

   • Close-up of single anther showing dehiscence

   • Pollen grains (if microscope available)

Pollination clue: Sticky pollen = animal-pollinated; Powdery pollen = wind-pollinated or loose-pollen flowers

d. CARPELS (Gynoecium/Pistil) - Center Whorl - FEMALE PARTS

Simple explanation: Carpels produce seeds. The bottom (ovary) contains eggs (ovules). After fertilization, the ovary becomes a fruit.

CRITICAL: Determine ovary position BEFORE removing carpel!

Step 1: Ovary Position Determination (VERY IMPORTANT!)

Why it matters: This is one of the most important features for plant identification.

Procedure:

1. Make longitudinal cut through flower center

   • Use sharp razor blade

   • Cut from top to bottom, through middle

   • Cut through calyx, petals, stamens, AND carpel

   • Be careful - steady hand!

2. Examine where parts attach relative to ovary

3. Determine ovary position:

 SUPERIOR (Hypogynous)

• Ovary sits on top

• Other parts attach below ovary

• Ovary is highest point in center

• Drawing: [Side view showing ovary above attachments]

 INFERIOR (Epigynous)

• Ovary at bottom

• Other parts appear to grow from top of ovary

• Ovary below attachment points

• Drawing: [Side view showing ovary below attachments]

 INTERMEDIATE/HALF-INFERIOR (Perigynous)

• Ovary partially embedded in cup-like structure

• Parts attach around middle of ovary

• Drawing: [Side view showing ovary half-embedded]

4. Sketch the cross-section showing ovary position

5. Photograph longitudinal section with ruler

Mohave County examples:

• Superior: Lupine, penstemon, mustards, most wildflowers

• Inferior: Sunflower family (brittlebush, desert marigold), cacti, evening primrose

• Perigynous: Rose family (Apache plume if available)

Step 2: Remove and Measure Carpel

Now carefully remove the entire carpel structure:

1. Count visible carpels (may be fused): _____

   • If fused, count stigma lobes to estimate

   • Unfused carpels are rare in common flowers

2. Number of locules (chambers) visible: _____

   • Will confirm when you cut cross-section

STIGMA (top part - receives pollen)

• Total pistil/carpel length: _____ mm (base to stigma tip)

• Stigma type: / Capitate (round knob at top - like a ball on stick) / Lobed (divided into sections) / Feathery/plumose (branched like feather - grass flowers!) / Linear (elongated) / Other: _____

• Stigma width/diameter: _____ mm

• Number of stigma lobes: _____ (Often equals number of fused carpels)
  
  
  

• Stigma surface: / Smooth / Papillate (covered with tiny bumps - feels rough) / Sticky/moist (has adhesive coating) / Dry (pollen just sticks mechanically)

• Stigma color: _____

Pollination clue: Feathery stigmas = wind pollinated (grasses); Sticky stigmas = animal pollinated

STYLE (middle part - connects stigma to ovary)

• Style length: _____ mm (base of stigma to top of ovary)

• Style diameter: _____ mm

• Number of styles: _____

  • Usually 1, but some flowers have multiple

• Style characteristics: / Straight / Curved / Branched / Hairy / Smooth

OVARY (bottom part - contains ovules/future seeds)

• Ovary length: _____ mm

• Ovary width: _____ mm

• Ovary shape: / Globose (round/spherical) / Ovoid (egg-shaped) / Cylindrical (tube-shaped) / Compressed (flattened) / Other: _____

• Ovary surface: / Smooth / Hairy / Ridged / Spiny / Warty

Step 3: Make Transverse (Cross) Section of Ovary

This reveals internal structure!

1. Cut through middle of ovary perpendicular to its length

   • Use sharp razor blade

   • Cut straight across (not angled)

   • Make thin slice (2-3 mm thick)

2. Observe internal structure carefully

3. Number of locules (chambers): _____

   • Count separate compartments

Each usually contains ovules 

4. Count ovules per locule: _____

   • Ovules are tiny, may need hand lens

   • Count in one locule, assume others similar

   • If too many to count: estimate as "numerous"

5. Total ovules in ovary: _____ (Locules × ovules per locule)

6. Placentation type (where ovules attach): / Axile - ovules attached to central axis in multi-locular ovary (most common) / Parietal - ovules on ovary wall in one-locular ovary / Free central - ovules on central column, no partitions / Basal - single ovule at base / Apical - ovules at top

7. Individual ovule size: _____ mm (if measurable)

8. Ovule color: _____ (usually white, cream, or pale green)

9. Photograph ovary cross-section with ruler

Important: The number of ovules tells you maximum possible seeds per fruit!

e. Final Documentation - Complete Dissection Display

Create your "dissection plate" - professional documentation!

1. Arrange ALL parts on white paper or poster board:

Layout (from top to bottom):

• Top row: Sepals (arranged as they appeared)

• Second row: Petals (arranged as they appeared)

• Third row: Stamens (spread out to show detail)

• Bottom: Carpel parts (ovary cross-section, style, stigma)

• Side: Intact flower (if you collected extras) for comparison

2. Create label card including:

   • Species name (scientific and common)

   • Collection location and date

   • Your name

   • Any special notes
     
     
     

3. Add scale bar (ruler or drawn scale)

4. Photograph from directly overhead:

   • Camera parallel to surface

   • Even lighting (no shadows)

   • Fill frame with specimen

   • Take multiple shots (different exposures)

   • Close-ups of interesting parts

This creates a permanent record of your work!

Step 4: Floral Formula Construction

What is a floral formula? A shorthand code that summarizes flower structure - like a chemical formula but for flowers!

Why it matters: Allows quick comparison between species; used in plant identification keys.

Floral Formula Format:

⚥ / ♂ / ♀ K(n) C(n) A(n) G̲(n) / Ḡ(n)

Symbol Key:

Sex symbols (first position):

• ⚥ = Perfect flower (bisexual - has both stamens and carpels)

• ♂ = Staminate (male only - stamens only)

• ♀ = Pistillate (female only - carpels only)

• ⚥♂ = Andromonoecious (some perfect, some male on same plant)

• ⚥♀ = Gynomonoecious (some perfect, some female on same plant)

Part symbols:

• K = Calyx (sepals)

• C = Corolla (petals)

• A = Androecium (stamens)

• G = Gynoecium (carpels)

Number notation:

• n = actual count (e.g., 5 = five parts)

• (n) = Parentheses mean parts are fused together

• ∞ = Numerous parts (more than 15, too many to count easily)

• 0 = Part absent

Special notation:

• + = Parts in distinct whorls (e.g., 5+5 = two whorls of 5)

• : = Parts of different lengths (e.g., 4:2 = four long, two short)

• G̲ = Superior ovary (underlined)

• Ḡ = Inferior ovary (overlined)

Step-by-Step Formula Writing:

Example: Desert Marigold (Baileya multiradiata)

Step 1: Determine sex

• Has both stamens and carpels → ⚥

Step 2: Count sepals

• Modified/reduced in composite flowers, tiny bracts → Use K0 or K∞

Step 3: Count petals

• Ray flowers: 13 petals (fused at base) → C(13) or approximately C(12-15)

• For sunflower family, often written as two flower types

Step 4: Count stamens

• 5 stamens, anthers fused into tube → A(5)

Step 5: Count carpels and determine ovary position

• 2 carpels (fused), inferior ovary → Ḡ(2)

Complete formula: ⚥ K0 C(13) A(5) Ḡ(2)

Your Turn - Write Formulas for Your Flowers:

Step 5: Pollination Syndrome Analysis

Based on your flower observations, predict the pollinator!

For each species, fill out:

Predicted pollinator: _____

Confidence: / High / Medium / Low

Reasoning: _____

Mohave County Pollinator Notes:

Common pollinators:

• Bees: Most common (native bees, honeybees, bumblebees)

• Hummingbirds: Present spring-fall (Costa's, Anna's, Black-chinned)

• Moths: Active at night (especially sphinx moths)

• Butterflies: Common in spring (painted lady, whites, swallowtails)

• Bats: Lesser long-nosed bat (agave flowers) - federally protected!

• Flies: Various species (bee flies, hover flies)

• Beetles: Less common but present

Seasonal timing:

• Spring (March-May): Peak diversity, most pollinator activity

• Summer monsoon (July-Aug): Second bloom, moths more important

• Fall: Hummingbirds migrating through

• Winter: Few pollinators, few flowers

Part 2: Fruit and Seed Development

Overview: Track how flowers transform into fruits and how plants package seeds for dispersal.

Step 1: Select Species for Developmental Series

Goal: Document multiple stages from flower → mature fruit

Choose 5 species where you can find:

1. Flowers (use from Part 1)

2. Young fruits (recently fertilized, small)

3. Developing fruits (intermediate size)

4. Mature fruits (full-sized, ripe)

5. Dispersal stage (seeds releasing/dispersed)

Best Mohave County Species for This:

Easy developmental series:

1. Puncture vine (Tribulus terrestris)

   • Weed, all stages present simultaneously

   • Develops quickly (weeks)

   • Flower → spiny fruit clearly visible

2. Russian thistle/Tumbleweed (Salsola tragus)

   • Abundant, all stages present

   • Entire plant becomes dispersal unit!

3. Desert dandelion (Malacothrix)

   • Flower → puffball progression

   • Classic wind dispersal

4. London rocket/Mustards (Sisymbrium)

   • Flower → long seed pod

   • Pods clearly visible
     
     
     
     
     

5. Filaree (Erodium)

   • Flower → "stork's bill" fruit

   • Interesting mechanical dispersal

In gardens/landscaping:

• Tomatoes, squash, beans (if available)

• Sunflowers (cultivated)

• Zucchini, pumpkins

Native shrubs (if fruiting):

• Wolfberry (Lycium)

• Apache plume (feathery fruits)

• Catclaw acacia (seed pods)

Step 2: Document Each Species

For each of your 5 species:

a. Basic Information

• Species name: _____

• Flower description (from Part 1, if you examined it): _____

• Stages available: (check all present) / Flower / Young fruit / Developing fruit / Mature fruit / Dispersal stage / Post-dispersal (empty)

b. Photography

For each stage present:

1. In situ (on the plant)

   • Show fruit attached to plant

   • Include scale

   • Show spatial arrangement (clustered? single?)

   • Date and time

2. Close-up (removed from plant)

   • Clear detail of fruit structure

   • Include scale bar

   • Multiple angles if complex

3. Developmental series (if possible)

   • All stages in one photo for comparison

   • Arranged in order: flower → young → developing → mature → dispersed

   • Scale bar

Step 3: Measure Developmental Stages

Track how fruits grow over time

For each stage of each species, measure:

Dimensional Measurements

• Length (base to apex, longest axis): _____ mm

• Width (at widest point, perpendicular to length): _____ mm

• Depth/thickness (3rd dimension if relevant): _____ mm

• Circumference (if roughly spherical): _____ mm

• Mass (if scale available): _____ g

Create Development Table:

Species: _____

Observations:

• Growth rate: / Fast (days) / Moderate (weeks) / Slow (months)

• Color change pattern: _____

• Texture change: _____ → _____ → _____

• Time from flower to mature fruit (if known): _____ days/weeks

Step 4: Fruit Type Classification

For the mature fruit of each species:

a. Basic Fruit Characteristics

Origin:

• Derived from: / Single flower (simple or aggregate) / Multiple flowers (multiple fruit)

• Number of carpels involved: _____

  • Look at your flower data from Part 1

  • May be visible in fruit cross-section

• Accessory tissues present? / Yes / No

  • Accessory = tissues other than ovary (receptacle, sepals, etc.)

  • Example: Strawberry "seeds" on surface, fleshy part is receptacle

Texture: / FLESHY - soft, juicy, edible / DRY - hard, papery, woody

If FLESHY:

• Entire wall fleshy (berry-like)

•  Only outer layers fleshy (drupe-like)

•  Only inner layers fleshy

If DRY:

•  Dehiscent - splits open to release seeds

  • How does it open? _____ (along seams, by pores, explosively)

•  Indehiscent - stays closed (seed inside)

b. Internal Structure Examination

Make cuts through mature fruit:

1. Longitudinal cut (lengthwise, tip to base)

   • Shows length of seed cavity

   • Shows placentation

2. Transverse cut (crosswise, through middle)

   • Shows number of chambers

   • Shows seed arrangement

3. Photograph both sections with ruler

Record observations:

• Number of chambers (locules): _____

• Seed arrangement: / Axile (on central axis) / Parietal (on walls) / Central (on column) / Scattered throughout

• Wall layers visible (if applicable):

  • Exocarp (outer skin): _____ thickness, texture

  • Mesocarp (middle layer): _____ thickness, texture

  • Endocarp (inner layer): _____ thickness, texture

c. Classify Fruit Type

Use this decision tree:

STEP 1: Simple, Aggregate, or Multiple?

 SIMPLE - From one carpel or multiple fused carpels of ONE flower / AGGREGATE - From multiple separate carpels of ONE flower (raspberry-like) / MULTIPLE - From carpels of MULTIPLE flowers (pineapple-like)

STEP 2: Fleshy or Dry?

If SIMPLE & FLESHY:

•  Berry - entire wall fleshy, many seeds (tomato, grape, cactus fruit)

•  Drupe - outer fleshy, inner stony pit, one seed (peach, cherry, olive)

•  Pome - fleshy from accessory tissue, core with seeds (apple - rare in desert)

•  Hesperidium - berry with leathery rind (citrus)

If SIMPLE & DRY & DEHISCENT (splits open):

•  Legume - splits along 2 seams, one chamber (pea pod, bean, acacia, lupine)

•  Follicle - splits along 1 seam (milkweed, Apache plume)

•  Capsule - splits various ways, may have multiple chambers

  • Splits: / By pores / By slits / Circumscissile (lid pops off)

•  Silique - two halves split, leaving central partition (mustards)

If SIMPLE & DRY & INDEHISCENT (doesn't split):

•  Achene - one seed, thin wall, seed not fused to wall (sunflower "seed")

•  Nut - one seed, hard thick wall (acorn, but rare in Mohave)

•  Grain/Caryopsis - one seed fused to fruit wall (grass seed)

•  Samara - achene with wing (maple, ash)

•  Schizocarp - splits into separate pieces (2-5), each with one seed (puncture vine!)

If AGGREGATE:

• Collection of small drupelets (raspberry) or achenes (strawberry)

If MULTIPLE:

• Fused fruits from many flowers (fig, mulberry)

Your classification:

Species: _____

Primary type: / Simple / Aggregate / Multiple

Specific fruit type: _____ (e.g., legume, achene, capsule, berry, drupe)

Key characteristics supporting this classification:

Confidence: / High / Medium / Low / Uncertain

Common Mohave County Fruit Types:

• Legumes: Lupine, acacia, mesquite pods

• Capsules: Evening primrose, penstemon

• Achenes: Sunflower family (brittlebush, desert marigold)

• Schizocarps: Puncture vine (breaks into 5 spiny segments!)

• Follicles: Milkweed, Apache plume

• Siliques: Mustards (long skinny pods)

• Berries: Cactus fruits, wolfberry

• Drupes: Desert olive