Silvi sytems specifics

Question 1

When is CC system the best to use?

Answer 1

• best suited to early serial species
• best on mesic sites where site sensitivity is not an issue
• visual issues not a concern
• fiber production is the main management
• planned artificial regen
• if site prep could damage residuals

Question 2

negative aspects of CC?

Answer 2

• lowest level of wildlife habitat retention

- lowest visual quality

Question 3

What is the point of the retention system?

Answer 3

• This approach is meant to address biodiversity issues by retaining structural elements of the original stand.
• Not intended for regeneration but to create structure. Not harvested until culmination of new stand.
• depends on minimizing distance between standing edges
• limited by species tolerance to shade, wind firmness, and accessibility during harvest.

Question 4

how does the retention system work?

Answer 4

patches of a stand are left standing while the rest is clearcut. patches to remain until next rotation.

Question 5

Describe the seed tree system?

Answer 5

Stand removed over 2 entries. Mostly harvested while seed trees are left behind to restock site. When regeneration is complete, seed trees are removed. Seedbed must be appropriate for seed.

Question 6

What are some important things to remember when using seed tree system.

Answer 6

• Choose healthy, wind firm trees with good phenotypes. Make sure the trees left behind will regen site quickly. (this is done by carefully monitoring stand so you know when you are going to have a good cone crop.)
• As long as you have met your stocking requirements, the regen destroyed while harvesting seed trees will be of minor consequence.

Question 7

On steep ground, which seed tree system would be preferred?

Answer 7

Group seed tree, because it will be easier to harvest a group. Seed travels further on slope so less trees needed.

Question 8

Why would you want to remove the seed trees as a pose to leaving them?

Answer 8

• If intolerant species, the seed trees will hinder development.
• seed trees are often the most valuable.

Question 9

What are two species that work well with seed tree?

Answer 9

Western larch and IDF in the interior.

Question 10

Why might you remove seed trees over 2 cuts?

Answer 10

to leave the understory time to adapt sun leaves.

Question 11

What 4 things determine how many trees per ha. to leave as seed trees?

Answer 11

• Species
• Slope (topo)
• Wind patterns
• size (8-80 ha)

Question 12

What is a general rule when comparing soil moisture and site sensitivity?

Answer 12

the higher the moisture, the more sensitive the site.

Question 13

How can you increase seed germination with the seed tree system?

Answer 13

• time harvest to maximize germination potential (keep in mind site sensitivity).
• plan for optimum wind dispersal.
• increase opening size (to an extent)

Question 14

Describe the shelterwood system

Answer 14

• Offers the highest level of stand protection by maintaining an understory at the same time as allowing the establishment of an even aged stand.
• longer time of establishment (20 y)

Question 15

What type of sites are the shelterwood system most suited to?

Answer 15

• sites that require continuous occupancy to stabilize and protect soils.
• sites that require good cover for wildlife/aesthetics
• tend to be drought prone or hot
• can be used on wet sites, but must be done when frozen

Question 16

What are the traditional shelterwood variations and how do they vary?

Answer 16

• uniform
• strip
• group
• natural
• nurse tree
  Irregular (transition)
  Differ by spatial arrangement of leave trees, entry period, time of over story removal, species composition by canopy layer (seed tree selection).

Question 17

why is shelterwood preferred on wet sites

Answer 17

• if wet site is clearcut, soil water table can drastically rise. By maintaining a minimum stocking level with shelterwood, site can regenerate with minimal impact on water table. —–Can be timed so that new stand is large enough to compensate for removal.

Question 18

How many entries are considered normal in a shelterwood system?

Answer 18

3-5

Question 19

explain the 3 standard entry phases of a shelterwood system.

Answer 19

Phase 1: “sanitation or preparatory” harvest where undesirables are removed. (Leaves behind desired species and phenotypes.)
Phase 2: “seed cut” where the only trees left are those that will be used for regeneration. (must leave appropriate #.)
Phase 3: “removal cut” of seed trees (can be done over 2 or 3 sub phases.)

Question 20

Why would site prep be required in shelterwood?

Answer 20

If desired species requires the soil to be prepared. (ex. some spp. need mineral soil for higher chance of germ.)
Also potential brushing for undesirable non crop vegetation.

Question 21

Not only is understanding the silvics of crops trees important but also…

Answer 21

The silvics of non crop vegetation that competes with seedlings.

Question 22

When would strip shelterwood be the best approach?

Answer 22

Sloped sites where visual concerns exist as well as wind prone sites. 20 m strips removed in sequence.

Question 23

What is the irregular shelterwood?

Answer 23

-Transition system to uneven aged structure. Ultimate site protection system but only possible with very tolerant trees.

Question 24

What is the natural shelterwood?

Answer 24

• After natural disturbance removes understory, residual natural over story is removed once they have regenerated the site.

Question 25

Nurse tree?

Answer 25

Overstory trees are left until understory is of an appropriate size to out compete brush.