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Can We Emulate Early Seral Forest Through Silviculture
1. Can we emulate early seral forest through silviculture? Klaus J. Puettmann Edmund Hayes Professor in Siviculture Alternatives Adrian Ares Research Associate Oregon State University
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6. Suislaw NF Willamette NF From Yang et al. 2005 Structural development of plantations Conifer cover
7. 20 years 6 years 13 years Management – Stand replacing disturbances ODF land OR Coast Range
8. Dave Powell, USDA Forest Service, Bugwood.org Management – Stand replacing disturbances “ Arrested” stand development Ceanothus after wildfire, Umatilla NF
9. P. Anderson, USFS L. Kayes L. Kayes 2 nd growing season 3 rd growing season Management – Stand replacing disturbances Impacts of legacies – Sprouts Timbered Rock, BLM
10. P. Anderson, USFS Management – Stand replacing disturbances Shrub removal No treatment Hardwood control initially maintains “open” structure
11. T. Harrington USFS Management – Stand replacing disturbances Intensive hardwood control accelerates dominance of conifers
13. Natural regeneration (no salvage logging or planting) suggest longer early seral phase Management – Stand replacing disturbances # dominant seedlings established
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15. > 15 feet = gap How many gaps are in ODF plantations? Management – Stand replacing disturbances Low density Gap Road Measurement line
16. Puettmann and Berger 2005 Management – Stand replacing disturbances Gaps contain early seral vegetation, but disappear as stands develop 0.0 2.0 4.0 6.0 8.0 10.0 12.0 1984 1986 1988 1990 1992 1994 1996 YEAR planted % area in gap
17. Spatial scale and variability Timber production Structural Diversity Management – Stand replacing disturbances
18. No management Management – keep gaps open Gap - scale Management – stand replacing disturbances Ongoing studies:
19. 6% of plantation in gaps Does wildlife notice the difference? Gap and stand scale Management – Stand replacing disturbances Ongoing studies:
20. YSTDS - Christy Flats Management – Partial disturbances Thinning and gaps = managing for early seral legacies in mature forests
21. Control High Moderate Variable density Modified from Berryman, unpubl. Management – Partial disturbances
22. Structural development: Herbs take advantage of disturbance Tall shrubs recover slow Study Results From Ares et al. 2009 Management – Partial disturbances
24. From Ares et al. 2009 Management – Partial disturbances Early seral herbs are responsive: structure and composition C = Control LC = Low complexity thinning MC = Moderate complexity thinning HC = High complexity thinning
25. Management – Partial disturbances Shrub layer slow to recover and dominated by “legacies” C = Control LC = Low complexity thinning MC = Moderate complexity thinning HC = High complexity thinning
26. Early seral vegetation 11-years after thinning Management – Partial disturbances “ Long-term” impact C = Control HD = High density MD = Moderate density VD = Variable density
Are not necessarily the same (green trees – cover and seed)
94 stands from the cascades and 59 from coast range Max age 50 clear-cutting was the cause of stand-replacing disturbance. Broadcast burning was usually applied to logging slash to reduce fire hazard, facilitate planting, and reduce competition from shrub species. Planting is commonly used in the two study areas for managed forest, and occasionally partial harvest is performed on managed stands in national forest. Various intensities and success of reforestation practices Various intensities and success of legacy removal Photo from George Fenn ownership
-thought this was striking to show the understory at age 20
Field of snowbrush ceanothus in intensely burned area in a 1986 wildfire near Jump-off Joe Ridge, NFJD RD, Umatilla NF
1. The orange moss in pics labeled trock_beargrass (this is Paul's pic from 2004 - 2 growing seasons post fire) is Funaria hygrometrica and Pteridium aquilinum dominant in the herbaceous layer 2.FUHY_landscape (from 2005 3 growing seasons post-fire) orange moss is again Funaria hygrometrica and is primarily beargrass in the herbaceous layer (Xerophyllum tenax). 3. DSCF0055 (2005 3 growing seasons post fire) - Shrubs taking over. Species are Ceanothus sanguineus, Arbutus menziesii and Acer macrophyllum.
Tanoak study year 9 – hardwood removal at year 2
Fig. 1. Age distribution of dominant tree regeneration in 2005 within low elevation fires of 1992-96 ( A ) low elevation fires of 1987 ( B ) and high elevation fires of 1987 ( C ) in the Klamath-Siskiyou region. Graphs are a composite of data from four, three and three fires, respectively ( A, B and C ). One fire was divided between ( B ) and ( C ) because of the elevation range it contained. These graphs indicate that tree regeneration in the Klamath-
Spatial eveness
Powerpoint turn y-axis label will turn L into i
-gaps close in quickly -thin to maintain openness of gap
-gap size selected to align with other gap studies -large scale approach to assess whether wildlife utilize or respond to these gaps
Increase in vegetation/herbs = early seral – no simple acceleration of late-successional features (species composition)
The competitor species group showed a symmetrical pattern in both gap sizes, whereas ruderal and stress-tolerator groups both showed a strong skew of the gap effect toward north sides of gaps regardless of gap size. Also, in both gap sizes, stress tolerator group was below reference forest levels on north, but not south, side of gaps (Fig. 2). be attributable to high abundance of ruderal species and low abundance of stress-tolerator species. Factors, such as physical disturbance and propagule availability, have a significant influence on understory species composition (Collins and Pickett, 1988a, 1988b; Beatty, 2003). Ruderal species are dependent on disturbance and physical disturbances of existing vegetation are certainly partly responsible for observed gap response (Fahey and Puettmann 2007). However, the directional nature of the response suggests this is not the only factor at work. The northward skew of these group distributions suggests a light driven control on the occurrence of ruderal and stress-tolerator species at levels different from those achieved in the adjacent thinned forests. On north sides of larger gaps, ruderal species are more likely able to replace stress-tolerator species presumably because they can benefit from high levels of direct solar radiation (Fahey and Puettmann 2007), which acts as a secondary disturbance on stress-tolerator species. [k1] This may help explain why gap influence on surrounding forests was minimal even in large gaps. Physical disturbance of existing vegetation outside of gaps is minimal, therefore, gap influence is likely to occur only in places where stress-tolerator species are eliminated by this secondary disturbance and are then replaced by either ruderal or competitor species. [k1] not sure I understand, something does not fit