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Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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Chapter 5 Forensic Botany
By the end of this chapter you will be able to:
5.1 Describe different forms of forensic botanical evidence.
5.2 Discuss how botanical evidence can help solve crimes
by linking a person or object to a crime scene, establishing a
postmortem interval, or aiding in the location of gravesites.
5.3 Discuss the history of forensic botany.
5.4 Explain the terms plant assemblage and pollen
fingerprint or pollen profile.
5.5 Summarize the roles of gymnosperms, angiosperms,
seedless plants, and fungi in terms of providing botanical
evidence.
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Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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Cengage/NGL/South-Western © 2016
Chapter 5 Forensic Botany
By the end of this chapter you will be able to:
5.6 Explain why botanical evidence is often overlooked.
5.7 Summarize the differences between botanical
evidence collection and habitat sampling.
5.8 Describe the correct procedures for collecting,
labeling, and documenting botanical evidence.
5.9 Explain why a forensic botanist should consult with
local individuals; meteorologists; and entomologists,
anthropologists, and wildlife specialists when
processing a crime scene.
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Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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Chapter 5
Vocabulary
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angiosperm
assemblage
forensic botany
forensic palynology
gymnosperm
palynology
pistil
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Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
pollen “fingerprint”
pollen grain
pollination
postmortem
interval (PMI)
spore
stamen
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Introduction
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Forensic botany is the application of plant science to
crime-scene analysis for use in legal cases.
Botanical evidence can help answer the following
questions:
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Where?
When?
Who?
What was eaten before death?
Was the body moved?
PMI?
Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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History of Forensic Botany
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Plato’s Phaedo
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Richard “Bruno” Hauptmann was convicted
of the kidnapping of Charles Lindbergh's son.
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Socrates’ self-administered death sentence of
poison hemlock
This was the first time that forensic botany
evidence was accepted as legal evidence during
a trial.
Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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History of Forensic Botany
(continued)
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The annual rings in a tree
are made of xylem cells.
The larger spring growth
rings are usually lighter
than the darker xylem
cells produced during the
summer.
The size of each annual
ring is affected by local
environmental conditions.
Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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How Forensic Botany is Used
to Solve Cases
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Plants grow in assemblages.
Assemblages are groups of plants usually
dominated by one species.
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Chapter 5
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Drowning Victims
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By comparing the number and proportion of
algae and diatoms in a drowned person’s
lungs and body tissues, it is possible, in
some cases, to determine where he or she
drowned.
Fewer than 20 different species of diatoms
indicate a recent drowning; more than 50
species indicate a longer postmortem
interval.
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Chapter 5
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Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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Information from Gastric
Contents
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Plant cells, with their cellulose cell walls,
can easily withstand digestion.
Dr. Jane Bock and her students created
a lab manual to assist in the identification
of plant cells in a person's last meal.
The manual was used to estimate
postmortem intervals based on the
degree of digestion.
Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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Secrets from a Grave
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In an old gravesite, the actual site sinks into
and fills the grave as the ground settles.
A new gravesite can be recognized by:
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A mound of soil
An absence of vegetation
Different plants on the gravesite than the
established dominant plants in the area
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Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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Botanical Crime-Scene
Analysis
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The crime-scene
photographer should take
images of:
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Dominant plants and other
plants
Depressed grasses indicating
possible entrances or exits
Broken branches or disturbed
plants
Plants that seem unusual for the
area
Plants in unusual locations
relative to the body, vehicle, or
object
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Searching for and Mapping
Botanical Evidence
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Botanical evidence
should be labeled with the
following information:
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Description of the plant
Height of the plant
Color and shape of flowers,
fruits, seeds, stems, and
leaves
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Botanical Evidence Collection
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At least 10 different types
of plants from the areas
assemblage, called a
habitat sample, should be
collected.
Botanical evidence is best
placed in paper.
Plants can be temporarily
stored using a plant press.
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Chapter 5
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Pollen and Spores in
Forensics
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Forensic palynology is the
study of pollen and spore
evidence to help solve
criminal cases.
Pollen and spores have
different functions, but they
have similar characteristics.
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Chapter 5
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Pollen Producers
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Plant reproduction is
either from non-seed
plants or seed plants.
Seed plants today
include:
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Gymnosperms
Angiosperms
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The basic reproductive unit of the
angiosperm is the flower.
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Types of Pollination
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Self-pollination
Cross-pollination
Some plants can both self- and crosspollinate.
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Methods of Pollination
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Pollen can be carried by wind, animals, or
water.
Wind-pollinated plants are often dominant
in the pollen profile of a crime scene.
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They may actually be overrepresented in
collection samples.
They may be less effective for determining
direct links between individuals and places.
Animals can pollinate flowering plants.
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Chapter 5
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Spore Producers
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Spores are asexually
reproductive
structures produced
by a variety of
organisms.
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Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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Pollen and Spore Identification in
Solving Crimes
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Spores are:
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Much smaller
and more
difficult to
identify than
pollen grains
Produced in far
greater
numbers than
pollen
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Chapter 5
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Pollen and Spore Evidence at
Crime Scenes
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Finding Pollen and Spores
Collecting Pollen and Spores
Analyzing Pollen and Spores
Forensic Science: Fundamentals & Investigations, 2e
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Summary
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Forensic botany and forensic palynology can provide
information about the geographic origin of a crime and the
time or season when it took place.
Knowing a crime-scene’s assemblage of plants can help
narrow down its location.
Forensic botany can help solve crimes based on plant
evidence found on or in a victim, on the suspect(s), or at the
crime scene(s).
Pollen is a reproductive structure containing male gametes
that is produced by seed plants. Spores are reproductive
cells produced by algae, fungi, and nonseed plants such as
ferns and mosses.
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Summary (continued)
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Seed plants including gymnosperms (cone-bearing plants)
and angiosperms (flowering plants) produce pollen.
Plants may disperse pollen in the wind or by the movements
of animals.
Pollen from wind-pollinated plants is more common in
forensic samples, but pollen from insect-pollinated plants
tends to provide more specific information about location.
Pollen evidence collected at a crime scene must be
compared with baseline samples from the area.
Collection of all botanical evidence must be performed
carefully to avoid contamination.
Forensic Science: Fundamentals & Investigations, 2e
Chapter 5
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