Alternative Regeneration StandardsKnowledge Gaps & Research Needs

Presented to:Foothills Growth and Yield Association

Technical Meeting – 5 March 2008

Presented by: Richard Briand – Hinton Wood Products

What do we know?

• Donald Rumsfeld:

– “…as we know, there are known knowns;there are things we know we know. We alsoknow there are known unknowns; that is tosay we know there are some things we do notknow. But there are also unknown unknowns -- the ones we don't know we don't know.“

Performance survey

• What do stands look like at age 14 years?

– What proportion of the stems are above BH?

– What proportion of the stems are below BH?How will these trees develop? Do theycontribute to harvest age yield? How are theymodelled in growth models? If they are at all.

– Can we reasonably model ingress? Shouldwe?

How important are trees <1.3m atage 14?

Treatment response

• How will treated stands develop?

– Post thinning development

– Post herbicide development

– Pose tending development

– Deciduous stems growing “under” conifer. Arethere any growth models that can reasonablypredict this? Should we just ignore these?

Diameter

• Diameters in young stands are difficult to assess(within reasonable error limits).

• What should we measure to assess the successof management/EFM treatments? If it’sdiameter….which diameter – DBH? DSH? D80?

• If we can’t reliably assess diameter, will we haveto wait until after the performance survey toshow the value of the treatments?

Density

• Some variables are not normally distributed, dowe need to compile these differently?

% plots

Trees / Plot

Height

• How useful is sampling top height in youngstands? If it’s not useful, what’s better?

• Are we measuring site index when we assesstop height in performance surveys? No…but weare assessing a consistent measure of height…a“Height Index” – how does this relate to siteindex?

• Should we measure average height?

• Should we measure the tallest trees (max ht)?

Height/Diameter Distributions

• Can we quantify the height and diameter distributions in “typical”young regenerating stands?

• Can we quantify the height and diameter distributions in “typical”natural stands? Our current growth models are built on these kindsof stands. When we use these models, we must understand whatthese differences are in order to interpret model results properly.

• How do these distributions change over time?• Could we incorporate these distributions into our sampling

protocols?• Could we make reasonable assumptions of the distribution of stems

below a measurement threshold?• How much do the “atypical” stands vary from the typical? What

percentage of our stands are “typical”?

Height Class Distribution

0.3-

0.8

0.8-

1.3

1.3-

1.8

1.8-

2.3

2.3-

2.8

2.8-

3.3

3.3+

% of stems

Height Class Distribution

0.3-

0.8

0.8-

1.3

1.3-

1.8

1.8-

2.3

2.3-

2.8

2.8-

3.3

3.3+

Can we “assume” thesetrees are present?

If we measure these?

Height Class Distribution

0.3-

0.8

0.8-

1.3

1.3-

1.8

1.8-

2.3

2.3-

2.8

2.8-

3.3

3.3+

But wehave toknowthis first!

Mixedwoods!

• ….actually mixed CONIFERS!

• Many silviculture folks are planting pine andspruce trees in regenerating blocks.

• Can we model development of these kinds ofstands?

Shrubs

Shrubs

• Are shrubs more prevalent in managed vs.natural stands?

• Are they beneficial?

• At what levels do they compete withcommercial species development? If any?

• Do we need to introduce this into growthmodels?

Growth

PerformanceEstablish-ment

Regeneration

Rotation

Time

Regeneration and Growth Phases

Establishment Performance

• We need to link stand conditions in theestablishment phase with those in theperformance phase, but…– What are the key variables?

– Is it really too chaotic to model, or have wejust assumed it is?

– If we have an objective of achieving a certainyield from a regenerating cutblock – how willour silviculture foresters determine what theyshould do at age 0?

Growth & Yield Programs

• We are collecting a tremendous amount ofdata at performance survey – intended toprovide an estimate of yield.

• How does ARS fit within an overall growthand yield strategy for an FMA?

Growth & Yield Programs

0

50

100

150

200

250

300

0 10 20 30 40 50 60 70 80

Stand age (years)

Vo

lum

ep

er

ha

(m3)

Esta

blis

hm

en

t

Pe

rfo

rma

nce

PSP Program ->

Regenerated Stand PSP’s

When does a new inventory take over?

How do we incorporateARS forecasts intothe G&Y program?- Empirical yield curves- Model derived yield curves

Advanced Growth

• Understorey protection (Sw under Aw):mixtures of advanced growth andseedlings. How should we assess thesecutblocks? Can we model thedevelopment of these stands? Do we evenhave the data necessary to build themodels?

• Same question for pine stands withunderstories after MPB attack.

MPB

• Will pine regenerate as well after MPBattack?

• Not so much an ARS question – but a pineregeneration question.

• What potential problems should weexpect?

• Are we going to have to plant more? Plantwhat species?

• How will mixed species stands develop?

Questions?