Unit B Section 1 Introduction Plants for Food and Fiber
Completion requirements
Section 1: Plant structures play specific roles in helping plants grow and thrive.
Unit B: Section 1 – Introduction
Figure B.S.1.1 – Douglas fir trees are the tallest trees in Alberta.
Figure B.S.1.2 – Giant sequoia trees can grow to 9 metres in diameter.
Giant Trees
What is the tallest tree that you have seen? The largest type of tree in Alberta is the Douglas fir. In the wet conditions of the British Columbia coast, for example, Douglas firs can grow to be 45 metres tall – about the height of a 13-storey building. However, a Douglas fir tree looks tiny compared to a giant sequoia or a redwood tree in the warmer and wetter conditions of northern California..
Currently, the tallest tree in the world is a coast redwood in California, USA. It’s name is Hyperion, and it is 115 metres tall – the height of a 35-storey skyscraper. Wow!
Figure B.S.1.3 – A hole was cut for cars to drive through this redwood tree in California, USA.
Watch More
Climbing Giant Redwoods
Photographers climbed some of the world’s largest redwood trees in California to take pictures of these massive trees. With various cameras, they took 84 photographs of one tree so we could have “the big picture”.
Photographers climbed some of the world’s largest redwood trees in California to take pictures of these massive trees. With various cameras, they took 84 photographs of one tree so we could have “the big picture”.
What is it like to climb a giant tree? Watch this video to find out.
Ancient Trees
Trees can live to be very old. Hyperion is about 700 years old. A few trees on earth are thousands of years old. A bristlecone pine tree that is more than 5000 years old was discovered in eastern California in 2013. The Canadian Rockies are host to several trees of more that 500 years old. Alberta’s oldest tree is a limber pine near the town Burmis in the Crowsnest Pass in southwestern Alberta. Unfortunately, it died in 1970 of old age – about 750 years old, but it is held up with steel rods as a point of interest.
The age of a tree in shown by the number of rings in a cross-section of that tree. Usually, we count the rings on the stump or the log – after the tree has been cut. Each ring represents a year of growth.
Click here to play a game about the information that tree rings give us.
Trees can live to be very old. Hyperion is about 700 years old. A few trees on earth are thousands of years old. A bristlecone pine tree that is more than 5000 years old was discovered in eastern California in 2013. The Canadian Rockies are host to several trees of more that 500 years old. Alberta’s oldest tree is a limber pine near the town Burmis in the Crowsnest Pass in southwestern Alberta. Unfortunately, it died in 1970 of old age – about 750 years old, but it is held up with steel rods as a point of interest.
The age of a tree in shown by the number of rings in a cross-section of that tree. Usually, we count the rings on the stump or the log – after the tree has been cut. Each ring represents a year of growth.
Click here to play a game about the information that tree rings give us.
Figure B.S.1.4 – Bristlecone pine trees grow in dry high mountains in western USA.
Figure B.S.1.5 – Tree rings are used to determine the age of trees.
Watch More
Studying Tree Rings
Instead of cutting a live tree, scientists can drill a thin sample from the tree trunk. From this core sample, they get information about the age and environment of the tree – and the tree can continue to grow, showing a new ring each year.
Instead of cutting a live tree, scientists can drill a thin sample from the tree trunk. From this core sample, they get information about the age and environment of the tree – and the tree can continue to grow, showing a new ring each year.
Words to Think About:
Check out the word cloud below. It pictures the important words that you are going to learn in this section. Watch for these words, and combinations of these words, as you read. When you see them highlighted, you can click on them to learn more about
what the word means. You can also visit the course glossary and read definitions for all of these words.
Lessons in This Section
Lesson B1: Plant Structures
Key Question – What are the main parts of the bodies of plants?
Lesson B2: How Water Flows in Plants
Key Question – How does water move to all parts of a plant?
Lesson B3: Photosynthesis, Cellular Respiration, and Gas Exchange
Key Question – How do plants make their own food?
Lesson B4: Plant Cells: Osmosis, Diffusion, and Active Transport
Key Question – How do nutrients move around a plant?
Reading and Materials for This Section
Science in Action 7
Reading: Pages 94–125
Materials Lists for Unit:
Lesson B5: Plant Growth and Life Cycle
Lesson B6: Plant Reproduction and Propagation
Key Question – How do plants grow from seeds to mature plants?
Lesson B6: Plant Reproduction and Propagation
Key Question – What are the various ways through which plants can reproduce?
Connections
Connections: Math
>> Triangles and Tree Height
Triangles with two 45-degree angles always have two equal sides. Likely, you will recognize these as right-angle triangles. We can use this mathematical relationship to determine the height of a tree.
>> Triangles and Tree Height
Triangles with two 45-degree angles always have two equal sides. Likely, you will recognize these as right-angle triangles. We can use this mathematical relationship to determine the height of a tree.
Try It!
Estimate Tree Height
Try this simple experiment to estimate the height of a tree.
Materials:
Try this simple experiment to estimate the height of a tree.
Materials:
- tape measure
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a tall tree
Instructions:
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Find a tall tree with lots of space around it.
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Walk 20 steps away from the tree. Stop with your back to the tree. Bend over and look between your legs, such as in Figure B.S.1.6. This causes you to be approximately at a 45-degree angle to the tree.
Figure B.S.1.6 - The correct position (really!) to estimate the height of a tree.
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If you cannot see the top of the tree, take 3 more steps from the tree, bend over, and look between your legs again. Repeat this until you can see the top of the tree by bending to look between your legs. Mark this spot.
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Measure the distance, in metres, from your marked spot back to the tree. This distance is approximately equal to the height of the tree.
Questions:
Think about the following questions very carefully. Then, type or write your answers. When you have your answers, click the questions for feedback.
Think about the following questions very carefully. Then, type or write your answers. When you have your answers, click the questions for feedback.
The shape formed by drawing a line from the top of the tree to your spot is a triangle. It should look similar to this diagram.
This method of estimating tree height will work for other trees – or buildings or towers or anything tall, if you always look at the top from a 45-degree angle. This method works best if you have lots of room to back away from the tree.