Module 2 - Optimizing Plant Resistance

ANNOUNCEMENTS

INTRODUCTION
Healthy trees are much more able to utilize internal resistance strategies to combat pests. So your next question is probably how does a horticulturalist maximize the chances of a plant being healthy?

Since horticulturalists are often involved in landscape design and installation one of the first and foremost things to promote health is proper plant selection. You should try to only use plants that are adapted to the local soil conditions and climate. You should also install plants at a density that maximizes air flow and limits overcrowding. Improved air movement can reduce disease and proper spacing insures plants have the resources they need for success.

Knowing the pests in your area is also a good place to start. There is no need to plant species that are susceptible to known problematic insects and diseases. Plant maintenance such as fertilization, irrigation, and even pruning (see poorly pruned specimen above, image source: elroySF)can be important in maintaining plant health and maximizing pest resistance.

LEARNING OBJECTIVES

• Describe the relationship between a healthy plant and increased pest resistance
  
• Explain how to maximize plant health through plant selection
  
• Describe how climate can impact plant health in the designed landscape
  
• Describe the relationship between seasonal growth, horticultural practices, and plant health
  
• Describe how to recognize a hazardous tree before a dangerous situation occurs
  

TERMS TO KNOW

• seasonal growth cycle
• climate, weather
• taproots, lateral roots
• canopy, drip line
• mycorrhizae
• root bound, circling roots
• resistant, less susceptible
• plant compatibility
• drainage, water infiltration, percolation
• root ball, field capacity, wilting point, soil moisture
• plant available water, unavailable water
  

READING and MULTIMEDIA ASSIGNMENT

1. Chapter 3. Growing Healthy Trees and Shrubs. pages 21-48 in your text
2. Read Stressed Out Plants
   
3. Watch YouTube Video on Hall's Landscape Tour
   
4. Watch YouTube Video on pruning large branches
5. Watch YouTube Video on Tree Planting
   

STUDY QUESTIONS

1. In a one page essay explain how proper plant selection and maintenance can improve plant health. Be sure your essay is rich with examples. (20 pts)
   
   
2. Based on what you have learned so far in the course explain how improved plant health could impact the types of management involved in an IPM program. (10 pts)
   
   
3. Watch the Hall Landscape Tour video again after reading Chapter 3. List practices utilized by this company that are covered in your text. (10 pts).
   
   
4. Describe in detail how soil type impacts plant growth and development. You may limit yourself to archetypal clay, loam, and sand soils. Be sure to include water relations in your discussion (20 pts). Those of you who have had HOR 166 Soils and Fertilizers will be aware of many different soil types based on texture.
   
   
5. Briefly discuss how improper pruning can lead to increased pest pressure. How do you implement the 3 cut pruning technique to remove a large branch? Be sure to list the purpose of each cut. (10 pts)
   
   
6. Describe to a new horticulture student how one might go about scheduling irrigation on a simple yard that was essentially 1/2 cool season grass and 1/2 large specimen trees. What types of irrigation equipment might you recommend for this site? Answer in complete sentences (20 pts)
   
   
7. You are going to plant 10 trees that arrive in 5 gallon plastic containers. Explain to your crew what to look for as far as the roots go. You can have the local nursery exchange any trees that you think are in poor condition and won't survive in the landscape. Describe the proper steps to plant the trees. How can planting a tree properly reduce future pest management issues (10 pts).

Look at this beautiful landscape integrated into the actual design of the building. Imagine the potential IPM practices necessary to keep this garden aesthetically pleasing. What do you think some of the challenges would be? This building is located in the planned communit of Foster City, CA (Image source: Peter Kaminski)

EXTRA CREDIT (2 pts)
Explain what ET is and how it can be used to maximize plant health.