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Module 2 – Turfgrass Anatomy and Identification
Lesson Title - How do we identify the various turfgrass species and why is identification
important?
Overview
Turfgrass surfaces are used for a variety of recreational and aesthetic purposes.
Depending on the application, turfgrass systems have different quality requirements.
Proper turfgrass growth, development, and management are essential to achieve
healthy turfgrass areas. Turfgrasses are characterized by unique anatomical features
which are necessary for identification between the various species. Proper identification
allows turfgrass managers to choose the best suited turfgrass species for the site based
on climatic adaptations, management strategies, and user needs.
Objectives:
Consider what determines a quality stand of turfgrass
Explain turfgrass growth and development
Properly identify turfgrass anatomical features
Use anatomical features to identify turfgrass samples
Discuss why turfgrass identification is important
Classify turfgrasses according to their use
Additional Readings:
Turgeon, A. J. (2007). Turfgrass Management. Upper Saddle River, NJ: Simon &
Schuster.
Gardner, D. (2012). Turfgrass Identification. Retrieved from
http://buckeyeturf.osu.edu/pdf/01_turfgrass_identification.pdf
Landschoot, P. (2012). The Cool-Season Turfgrasses: Basic Structures, Growth, and
Development. Retrieved from http://cropsoil.psu.edu/turf/extension/factsheets/pdfs/coolseason.pdf
Turgeon, A. J. (2006). Seed Structure and Identification of Cool Season Turfgrasses.
Retrieved from
http://turfgrass.cas.psu.edu/education/turgeon/Modules/02_GrowthandDevelopment/Se
edStructure/SeedStructure_text03.html
PP Slide 12 - Do you have any type of animation that shows the stages of growth from
seed to mature plant?
Quiz:
What are some factors that determine a quality stand of turfgrass?
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density, texture, uniformity, color, elasticity, rooting, and recuperative capacity
Explain the process of turfgrass seedling germination.
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The germination process begins when water is absorbed by the seed. This helps
break down starch in the endosperm to simpler carbohydrates for nourishing the
embryo. All structural components of the seedling grass plant arise from the
embryo.
Enlargement of the coleorhizae via cell elongation, accompanied by the
emergence of root-hairlike structures from the coleorhizae anchor the embryo to
the soil and function in absorbing water.
The primary root (radical) pushes through the side of the coleorhizae and
penetrates downward through the soil.
The coleoptile, a sheath of translucent tissue surrounding the growing point,
emerges above the soil surface.
Within the emerging coleoptiles, the first leaf elongates and pushes out through a
pore at the tip of the coleoptile. Photosynthetic activity begins, and soon the
seedling becomes entirely independent of the endosperm for its food supply.
The seedling is now considered to be autotrophic. (The seedling is considered
heterotrophic when it is entirely dependent on the endosperm for food.) If seeds
are buried too deeply in the soil, food reserves in the endosperm may become
depleted before the seedling is capable of manufacturing all its complex organic
compounds through photosynthesis and associated biochemical processes.
Seedling death may result.
The growing point of the seedling is enclosed within the coleoptiles. The second
leaf also grows through the coleoptiles and within the fold of the first emerging
leaf. Eventually the coleoptile withers away, and only leaves are evident above
the soil surface. Each succeeding leaf develops from the growing point and
upward within the older enclosing leaves.
The next seedling structures that form are the roots. Adventitious roots develop
from nodes at the base of the new shoot and become the primary root system in
mature plants.
What are some features used to identify turfgrasses?
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Growth habit, vernation, ligule, collar, auricles, leaf tip, leaf surface, inflorescence
What are rhizomes and stolons on grass plants?
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horizontally growing shoots that grow outward from the parent shoot
What does vernation mean?
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orientation of a newly emerging leaf
What are the two types of vernation on grass plants?
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Rolled and folded
What are the three types of leaf tips that characterize turfgrasses?
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Pointed, rounded, boat-shaped
What is the inflorescence?
- flowering part of the grass plant that bears seeds
Why is turfgrass identification important?
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Climatic adaptation, management practices, user needs
Please name the structures.
Please name the structures – Answer Key
Seedhead
Blade
Ligule
Sheath
Auricles
Midrib
Collar
Stolon
Leaf Bud
Crown
Rhizome