LESSON PLAN

Area and/or Course Horticulture

Lesson Title Pruning Evergreens

No. Periods 1 (73-minute period)

Teacher Goal(s):1. Students will be able to articulate the rationale for

pruning evergreens2. Students will demonstrate pruning evergreens

Rigor/RelevanceFramework

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CAssimilation

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DAdaptation___X____

AAcquisition

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BApplication

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1 2 3 4 5Application

Objectives:

The student will be able to (TSWBT). (Oregon Skill Set numbers in parentheses at the end of the objective statement.)

1. Identify characteristics and examples of evergreen plants (Plant 01.02.03.a)

2. Compare and contrast evergreen plants with deciduous plants (Plant 01.03)

3. Articulate the effects of improper pruning on evergreen plants (Plant 01.03)

4. Demonstrate proper branch removal in order to prevent tree injury (Plant 02.01.02.c)

5. Research the methods of pruning a specific evergreen plant (English IL.HS.RE.05)

State Standards met by Objectives:

Subject Strand Eligible Content

1. Plant 01.02.03.a Identify the components and the functions of plant stems

2. Plant 02.01.02.c Design, implement and evaluate a plan to maintain optimal conditions for plant growth

3. Plant 01.03 Apply knowledge of plant physiology and energy conversion to plant systems

4. Plant 03.03.05.b Demonstrate proper techniques to control and manage plant growth through mechanical,

cultural or chemical means5. Agriculture 02.01.01.02 Increase reading skills through reading challenging

material6. Agriculture 06.02.04.01 Identify general workplace safety hazards7. English EL.HS.RE.05 Match reading to purpose--location of information,

full comprehension, and personal enjoyment.

Knowledge: 1=awareness; 2=comprehension; 3=application; 4=analysis; 5=synthesis; 6=evaluationApplication: 1=knowledge in one discipline; 2=apply knowledge in one discipline; 3=apply knowledge across disciplines; 4=apply knowledge to real-world predictable situations; 5=apply

knowledge to real-world unpredictable situations

Materials, Equipment, Audio-Visual Aids:

1. Whiteboard

2. Masking Tape

3. Internet access

4.

5.

References:

http://cmg.colostate.edu/gardennotes/618.pdf

http://www.hort.purdue.edu/ext/evergreens.html

Anticipatory Set/Introduction/Motivation/Interest Approach:

Review Yesterday’s Lesson:

Students will be asked to talk about pruning fruit trees. The teacher will ask questions like:1. What went wrong and what went right when pruning the fruit trees?2. Were any mistakes caught before they happened? 3. How many people made improper cuts? 4. Who can tell me why we prune fruit trees?

Set:

Students will be shown a picture of a mature landscape. Four to five minutes will be given for students to analyze the picture. It will be a competition with the rest of the class to identify plants, compare and contrast differences in plant material, and describe the layout of the landscape.

After students have completed the activity the teacher will have students write their notes about the picture on the board. The point which will need to be emphasized are the fact that there are both evergreen and deciduous plants in the landscape.

Transition (Use Objective): Identify characteristics and examples of evergreen plants

Compare and contrast evergreen plants with deciduous

Articulate the effects of improper pruning on evergreen plants.

Demonstrate proper branch removal in order to prevent tree injury

Research the methods of pruning a specific evergreen plant

Strategy – Includes Teacher Activity, Student Activity, Questions/Answers and Objectives

Subject Matter Outline/Problem and Solution (Application Points Lace in Throughout Lesson) (Modeling, Guided Practice, and Content)

Objective #1

(Q) What does the name evergreen tell you about this category of plants?

(A) The plants are green year round. Always-green

(Q) What are some examples of evergreen plants?

(A) Pines, firs, rhododendrons, arborvitae, spruces, and many more plants which remain green year-round.

“What are Evergreens”

(DEF) Evergreen trees and shrubs keep their leaves year round.

Pines, firs, rhododendrons, arborvitae, spruces, and many more plants which remain green year-round.

Objective #2The teacher refers back to the anticipatory picture and asks students to count about how many evergreen trees and shrubs are in the picutre color, smell, color, size of overall plant, etc. color, smell, color, size of overall plant, etc.

(Q) Using your definition of evergreen; What do you think deciduous plants mean?

(A) Deciduous is the opposite of evergreen meaning it loses its leaves or needles during a part of the year

Students will be out in the

“What is the difference between evergreen and deciduous?”

(DEF) shedding foliage at the end of a growing season.

A deciduous plant (tree or shrub) will go dormant (its rest period) beginning when either the weather starts becoming colder (40’s to 50’s) or when an area experiences a hard frost (temperatures dropping below 32 degrees, usually overnight). It will begin to lose its leaves at this time. Blooming plants have specific periods when they bloom. They aren’t always in bloom. Many will bloom either in spring or summer.

“Evergreen” is used to describe plants (trees/shrubs) that do not go dormant and retain their leaves or needles. This generally refers to pines, spruces, boxwoods, junipers, yews and holly. Broadleaf evergreens are plants that retain leaves (very thick leaves) year round. But, they do shed the leaves periodically. This will apply to plants such as azaleas, rhododendrons and

landscape of the school or land lab and be able to look at differences between deciduous and evergreen plants and write down the differences to bring back and share with the class. Differences could include branch size, branch color, smell, color, size of overall plant, etc.

photinia.

Objective #3

(Q) As with most plants, is improper pruning likely to kill the plant?

(A) No, but improper pruning can permanently affect the looks of a plant

(Q) If a branch is removed from a pine tree, how long will it take for the branch to grow back?

(A) The branch will most likely never grow back.

(Q) What are some of the reasons for removing a branch from evergreen trees?

1. Dead material or disease

2. Improper crotch angle3. Growth in wrong

direction

What is the first step in pruning evergreens?

Removing dead material

“How to Prune Evergreens”

Evergreens require a different manner of pruning than other landscape plants. Although a plant is not likely to die from improper pruning, it is important to note that most evergreens cannot replace lost growth the way that deciduous plants can.

So while other landscape plants might be able to outgrow an errant pruning job, evergreens can suffer permanent disfigurement.

Individual plants should be assessed for pruning needs. Evergreens that have been sheared into formal or artificial shapes require frequent pruning. However, many evergreens may rarely need pruning.

As with other plants, the first objective of pruning is to remove any dead or damaged wood. Prune back to a branch that is pointed in the direction that you want the new growth to go, always making sure to cut back into healthy wood.

The term evergreen is used to refer to many different kinds of plants and all are not pruned in the same manner. Trees such as spruce and pine have very different pruning requirements than shrubs such as yew and juniper.

If frequent pruning is necessary to keep plant growth in bounds and prevent interference with a walk, driveway or view, consider replacing the plant. Evergreen trees and shrubs are pruned according to species growth characteristics.

(Q) How many central leaders should an evergreen tree maintain?

(A) 1

(Q) What happens to a single leader is removed?

(A) Growth will lower and wider making the tree not grow in natural forms.

Teacher will show students outside what the central leader is and show students evergreen shrubs which are absent of a central leader

Central Leader Information

On evergreen trees, avoid pruning the central leader (trunk). This results in the development of multiple leaders that are prone to wind and snow damage.

If the central leader is killed back, select one branch to become the new leader and remove potential competing leaders.

Never allow co-dominant trunks (trunks of similar size) to develop. If multiple trunks begin to develop, select one and remove others.

For structural integrity on evergreen trees, all side branches should be less than half the diameter of the adjacent trunk (less than one-third is preferred). If the diameter of a side branch is too large, prune back part of the needled area to slow growth or remove the branch entirely back to the trunk.

Objective #4

(Q) Why is it important to properly remove larger branches from evergreen trees?

(A) So the trunk is not damaged

(Q) How close to the tree should cuts be made?

(A) Close to the trunk without damaging the branch collar

Teacher will show students what the branch collar is

(Q) Should a cut be made straight through a large branch or using several cuts?

“Removing plant material”

New needles will not grow from branches without needles. When a side branch is removed on an evergreen, cut back to the trunk just outside of the branch collar (the enlarged connecting area on the trunk around the limb).

Do not cut into or otherwise injure the branch collar. Do not make flush cuts. Remove the branch in a three cut method.

(A) Several cuts should be used to prevent the branch from ripping bark off the tree and minimizing damage

Teacher will demonstrate the three cut method for large branches

In groups, students will mark cuts on a larger branch using masking tape and to minimize the possibility of damaging the tree.

The teacher will go to each group’s tree and double check the masking tape markings

(Q) Why is it so important we double check and triple check our cuts on evergreen trees?

(A) The branches will not grow back

Cut 1. Coming out 12-15 inches from the trunk, make an undercut a third to half way through the branch.

Cut 2. Moving a couple inches out past the 1st cut, make the second cut from the top, removing the branch. This double cutmethod prevents the weight of the branch from tearing the branch below the branch collar.

Cut 3. Make the third and final cut just outside the branch barkcollar. Take extra caution to not cut into or otherwise injurethe branch bark collar.

Objective #5

Students will be assigned to a specific evergreen tree to research, and write up a short paragraph about how to prune and draw a figure to represent how the cut would look.

The teacher will grade the writing on:

1. Grammar2. Complete Sentence

structure3. Correct content

The teacher will grade the

“How to Prune”

Spruce, fir, and Douglas-fir generally need little to no pruning.On young trees, pruning is useful in situations where bushier new growth is desired. Since these species produce some side buds, branch tips can be removed encouraging side bud growth. Prune late winter or early spring.

drawing on:1. Effort2. Correctness3. Color

Objective #3 Review

To review the research assignment with the students, the teacher will ask questions about the types of cuts to use of evergreens, and effects of improper pruning.

(Q) Generally, should shearing cuts be made on evergreens?

(A) No

(Q) What happens when shearing cuts are made on evergreens?

(A) Dense foliage growth and weak interior growth

(Q) If evergreen shrubs are pruned back too far; What can happen?

(A) Permanent empty spot could occur

While shearing is quick and easy, it is not recommended, especially after mid-summer. Shearing creates a dense growth of foliage on the plant’s exterior. This in turn shades out the interior growth and the plant becomes a thin shell of foliage.

Frequently sheared plants are more prone to show needle browning and dieback from winter cold and drying winds.Any pruning that tapers in towards the bottom of the plant will lead to thinning of the lower branches due to shading. To keep the bottom full, the base of the shrub needs to be wider than the top portion. It’s common to see junipers and arborvitae that have overgrown their space.

Since new growth comes ONLY from the growing tips, branches cannot be pruned back into wood without needles. If the shrub is pruned back to bare wood, it will have a permanent bare spot.

For shrubs that are getting too large, it is better to prune them back as they begin to overgrow the site. Pruning back of severely overgrown shrubs generally gets into wood without needles. Consider replacing severely overgrown plants with smaller cultivars or other species. Junipers and arborvitae growing in the shade are rather intolerant of pruning due to slow growth rates.

Closure/Summary/Conclusion (Tie in Objectives)

The teacher will go through the lesson and discuss each objective.

Identify characteristics and examples of evergreen plants

Compare and contrast evergreen plants with deciduous

Articulate the effects of improper pruning on evergreen plants.

Demonstrate proper branch removal in order to prevent tree injury

Research the methods of pruning a specific evergreen plant

Evaluation: (Authentic forms of Evaluation, Quizzes, or Written Exam)

Verbal check for understanding to include the following questions:1. How is pruning evergreens different than pruning apple trees?2. Why is it important to carefully prune large evergreen branches?3. How long will it take an evergreen branch to grow back after it has been removed?4. What is the importance of the central leader?5. How do you prune a juniper?

Assignments: (Student Activities Involved in Lesson/Designed to Meet Objectives)

1. Daily Calendar2. Compare and contrast sheet for evergreens and deciduous plants3. Evergreen research paragraph and drawing

Lesson Reflection

This lesson went faster than the fruit tree lesson, mostly because we didn’t have to recover information about types of pruning cuts. I feel like students have a good grasp on what they have learned about pruning cuts and how to make them throughout the work sample so far. If I were to do it over again I would try and find a way to take a field trip into the forest where a forester could tell us about pruning evergreens in relation to forest fires. I think it would be very beneficial for students to see how 150 years ago, small forest fires used to come through and burn the lower branches, but now that fire has not been a large player in the ecosystem and branches sometimes reach clear to the ground fires have intensified.