Plants Around Us: Trees, Grasses, and Flowers - First Grade Science
No matter where you live on Earth, you are surrounded by an incredible variety of plant life. Plants have adapted to live in almost every environment imaginable, from city sidewalk cracks to dense wooded forests, wide open grasslands, and sunlit wildflower meadows. While all green plants share basic needs, they come in different sizes, shapes, and forms. Three of the most common and important plant types you see every day are trees, grasses, and flowering garden plants.
Trees: The Giants of the Plant World
Trees are the largest, tallest, and longest-living plants on our planet. Some giant redwood trees grow taller than thirty-story buildings and live for thousands of years!
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| ANATOMY OF A TREE |
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| {;;;;;;;;;;;;;;;} |
| {;;;;;;;;;;;;;;;;;;;} <--- CROWN |
| {;;;;;;;;;;;;;;;;;;;;;} Branches & leaves |
| {;;;;;;;;;;;;;;;;;;;} catching light. |
| {;;;;;;;;;;;;;;;} |
| ||| |
| ||| <--- TRUNK |
| ||| Thick woody stem |
| ||| with tough bark. |
| =============|||============= Ground Level |
| / | \ |
| // | \\ <--- TAP & SPREADING |
| // | \\ DEEP ROOTS |
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Trunks and Bark
Unlike small plants with soft green stems, a tree has a single thick, woody stem called a trunk. The outside of the trunk is wrapped in rough bark. Bark acts like a protective armor, defending the tree against freezing winter cold, scorching sun, forest fires, and insect damage.
Deciduous vs. Evergreen Trees
Scientists divide trees into two major groups based on what happens to their leaves during the changing seasons: Deciduous Trees: These trees have broad, flat leaves. In the autumn, their leaves change from bright green to brilliant red, orange, and yellow before dropping to the ground. During winter, deciduous trees rest with bare branches. Examples include maples, oaks, and birch trees. Evergreen Trees: These trees keep their green leaves or needles all year round, even during freezing snowy winters! Many evergreen trees have slender needle-like leaves coated with a waxy layer and produce woody pinecones. Examples include pines, spruces, and firs.
Grasses: The Resilient Ground Cover
Grass covers more than a quarter of all the land on Earth. It carpets school playgrounds, front lawns, rolling hills, and vast African savannas where zebras and antelopes graze.
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| THE GRASS PLANT |
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| \ | / <--- SEED HEAD: Holds tiny grain seeds. |
| \|/ |
| | |
| / | <--- BLADE: Narrow, flexible leaf that |
| / | bends in wind and under footsteps. |
| | | |
| ======|====== Ground Level |
| GROWTH NODE: Located at base, near ground level! |
| / / | \ \ |
| / / | \ \ <--- FIBROUS ROOTS: Dense tangled net. |
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Why Grass Can Be Mowed and Grazed
Most plants grow from the tips of their stems; if you snip the top off, the plant can be severely damaged. Grass is uniquely adapted to survive being eaten by animals or cut with a lawnmower because its growing point (node) is located right at the base of the plant near the ground. When the blade is trimmed, the grass simply grows right back from the bottom!
Dense Fibrous Root Systems
Grasses have thousands of fine, intertwined roots that form a dense sod just below the surface. This thick mat holds the topsoil together, preventing powerful rainstorms and winds from washing valuable soil away.
Wildflowers and Garden Flowers
Flowering plants come in an endless variety of shapes, sizes, and colors. Some, called annuals, sprout, bloom, make seeds, and complete their entire life cycle in a single summer season. Others, called perennials, bloom every spring and summer, die back to the ground in winter, and return faithfully every year from hardy underground roots.
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| COMPARING TREES, GRASSES, AND FLOWERS |
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| FEATURE TREES GRASSES FLOWERS |
| Stem Type Hard woody trunk Hollow, flexible Soft green |
| Height Very tall Low to medium Short to tall |
| Lifespan Decades to centuries Varies 1 to many yrs |
| Leaf Shape Broad or needle Narrow blade Wide, varied |
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Caring for Plants in Our Community
Plants give us shade on sweltering days, clean the air we breathe, prevent soil erosion, and give animals safe homes. By planting gardens, watering neighborhood trees, and respecting green spaces in parks, you help preserve the lush plant world that keeps our planet healthy.
Chapter Review Exercises
Question 1: What is the main difference between the stem of a tree and the stem of a garden daisy?
Question 2: Explain the difference between a deciduous tree and an evergreen tree.
Question 3: Why is grass able to survive being walked on and trimmed by lawnmowers without dying?
Question 4: What important role do the dense root systems of grasses play in protecting the soil?
Solutions and Explanations
Solution 1: A tree has a thick, tall, hard woody stem called a trunk covered in protective bark, whereas a garden daisy has a soft, flexible, green stem that does not contain wood.
Solution 2: A deciduous tree has broad leaves that change color and drop off every autumn, leaving the branches bare through winter. An evergreen tree keeps its green leaves or needles throughout the entire year, even in cold snowy winters.
Solution 3: Grass survives being walked on and cut because its growing point is located down at the base of the plant right against the soil, rather than at the top of the leaf blades. Cutting the tips leaves the growth base unharmed to sprout new growth.
Solution 4: The dense, tangled fibrous root systems of grasses form a thick underground net that binds soil particles tightly together, preventing heavy rainfall, rushing runoff, and strong winds from washing or blowing away fertile topsoil.