Plant taxonomy is the science that finds, identifies, describes, classifies, and names plants. It is one of the main branches of taxonomy
In this collection there will be a bunch of plants with their Identification, classification and description .
This collection is useful for agricultural engineering and health students and everyone interested in plants
TAXONOMY: THE STUDY OF IDENTIFICATION,
CLASSIFICATION, AND NOMENCLATURE
A COMBINATION OF SCIENCE AND
ART
Taxonomy or Plant Systematics, despite what people would have
you believe, really is not an exacting science in many ways
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This statement mainly applies to the identification process, so
we’ll start there.
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Identification is very different from classification, which is
even more problematic
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There are several methods for identifying plants
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Many books rely on matching a description or illustration with
the plant you have in hand
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Most people first go to books with color photos, but actually
good line drawings can show more detail
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Books with color photos or drawings often are arranged by
color, but this is imprecise because of different color
perceptions by different people, and some genera fall in many
color categories, making finding the species difficult
The vast majority of horticulture books use the color or form
method for identifying rather than discrete, consistent
characters
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Besides Bailey’s
Encyclopedia of Horticulture
and a few others,
few horticulture books cover the whole spectrum of garden
plants, leaving many possibilities out
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Few horticulture books address a
Key
for correct identification
(more about keys in a moment)
If you’re interested in a special group of garden plants like
roses, chrysanthemums, and cacti there are books covering
those subjects in fair detail, making i.d. somewhat more
practical
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Currently, the best way to id garden plants is by learning to
key to family and then consulting books on genera, if available
Identification of native plants, by contrast, is often a surer thing;
many states have floras of their native plants
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Even better for the beginner are books specializing in one
particular geographic area, such as Marin County
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The majority of these i.d. books contain not only some
illustrations, but
dichotomous keys
for making a
determination
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The inexact part of this aspect of i.d. is because keys contain
many inconsistencies and sometimes just plain mistakes
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The other inexact part is that plants vary a lot in the wild, and
no keys take all of the variation into account
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For example, the genus
Fragaria
(strawberry) has flowers with
5 petals, but occasionally an individual will display 6 petals,
instead. This could completely mislead the identifier because
number of flower parts is heavily emphasized
Dichotomous keys also require knowledge of terminology, since
many terms are more precise than using ordinary words
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With flowering plants, the starting point is usually
determining if your plant is a
monocot
or
dicot
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Those two major categories are based on several traits, but
the terms themselves refer to the number of seedling
leaves—two for dicots, one for monocots
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This trait is impractical to use in most cases, since plants lose
their seedling leaves soon after germinating
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There are also exceptions to the number of cotyledons, as
there also are for most criteria to recognize these two groups
Fortunately, there are other rules that help determine monocots
and dicots, which are easier to apply
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The two most important traits are leaf vein pattern (veination)
and numbers of petals and sepals
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Dicots usually have a network or featherlike pinnate pattern
of veins while
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Monocots have the major veins parallel to each other
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However, there are occasional exceptions
and
some leaves
don’t show an obvious vein pattern
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For petal and sepal number, dicots have 4 or 5 (except for
some early dicots that have a large number),
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Monocots have 3 or multiples of 3
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Again there are occasional exceptions
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There are other traits for the two groups but many, like pollen
details and wood anatomy are difficult to deal with
Cow parsnip,
Heracleum maximum
, has leaves with a pinnate
vein pattern and is a dicot