DRL MGMT

Question 1

How to manage for low levels?

Answer 1

Condsider favoured alternate species for regen

Question 2

how to manage for moderate infection?

Answer 2

Definitely a concern

Use a passive approach (alt spp) unless you are on a high productive site.

Question 3

how to manage for high levels of DRL?

Answer 3

-Innoculum removal by stumping becomes a consideration depending on site sensitivity.

Question 4

When deciding on planting vs stumping, what are the 4 main considerations.

Answer 4

• Site productivity (If high then there is a $ benefit to remove infection)
• Site sensitivity (compaction, erosion) typically need 30-70% coarse frag.
• Operational feasibility (slope)
• Other values (fish, recreation, water.)

Question 5

When would you need to survey for DRL?

Answer 5

If low or high, the management choice is obvious. Surveys are required in moderate infection areas.

Question 6

What is important about the survey sample area?

Answer 6

Stratify survey if the infection is concentrated. Important to know where the infection is.

Question 7

What are the 3 levels of DRL infection

Answer 7

Low (5%) - Mod (10%) - High (15%)

Question 8

What are the two types of ground survey?

Answer 8

Area Based

Tree Based

Question 9

How are ground based surveys carried out?

Answer 9

Strips are run off baseline

• Intersection length method (infected length/total length)
• Sketch mapping area (draw line halfway between healthy and infected)

Question 10

How do you detect stressed trees with an aerial photo

Answer 10

False color composite reveals near infrared waves to use which can detect stressed trees (less chlorophyl)

Question 11

When surveying during harvest and regen, what information effects how you will manage?

Answer 11

• Individual centers vs stratified disease (stump if you want to replant fir where DRL is stratified)
• Alt spp (pine hardwood cedar)

Question 12

If you stump for DRL, what do you replant?

Answer 12

Fd, because infection is gone.

Question 13

What are the removal methods for DRL?

Answer 13

• Stumping (rip out stump and turn it upside down) mycostasis by antagonistic organisms takes care of the rest.
• Push over harvest (machine pushes tree over)

Question 14

What is innoculum avoidance?

Answer 14

Planting alt spp within 5m radius of DRL during regen.

Innefective unless stumps are marked reliably.

Question 15

What is bridge tree removal?

Answer 15

avoiding innoculum by removing healthy looking trees adjacent to disease center.