Predicting average growth and size distributions of Douglas-fir saplings competing with sprout clumps of tanoak or Pacific madrone

New Forests ◽  
1991 ◽  
Vol 5 (2) ◽  
pp. 109-130 ◽  
Author(s):  
Timothy B. Harrington ◽  
John C. Tappeiner ◽  
Thomas F. Hughes
Keyword(s):  
Douglas Fir ◽  
Size Distributions ◽  
Average Growth ◽  
Pacific Madrone

Bigleaf maple seedling establishment and early growth in Douglas-fir forests

1988 ◽  
Vol 18 (10) ◽  
pp. 1226-1233 ◽  
Author(s):  
Jeremy S. Fried ◽  
John C. Tappeiner II ◽  
David E. Hibbs
Keyword(s):  
Seed Predation ◽  
Seedling Survival ◽  
Seedling Emergence ◽  
Early Growth ◽  
Douglas Fir ◽  
Stand Development ◽  
Size Distributions ◽  
Canopy Density ◽  
Successful Establishment ◽  
Survival Of Seedlings

Survival, age and height distributions, and stocking of bigleaf maple (Acermacrophyllum Pursh) seedlings were studied in 1- to 250-year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stands in western Oregon to identify the stages in stand development in which bigleaf maple is most likely to establish successfully from seed. Maple seedling emergence averaged 30–40% where seeds were planted and protected from rodents but was typically <2% for unprotected seeds. Seedling survival after 2 years was highly dependent on canopy density, measured by percent sky. Average 1st-year survival of seedlings originating from planted, protected seeds was highest in clearcuts (1–2 years old, 36% survival, 56% sky) and pole-size stands (41–80 years old, 30% survival, 17% sky) with sparse understories and canopies. It was lowest in young stands with dense canopies (20–40 years old, 4% survival, 8% sky) and old stands (81–250 years old, 14% survival, 13% sky) with dense understories. Naturally regenerated populations of bigleaf maple seedlings, which occurred in aggregations (0.005–0.04 ha in area), were most abundant (up to 10 000/ha) in pole-size Douglas-fir stands. Although seedling size distributions within stands had a strongly inverse J shaped form, size distributions within aggregations appeared more normal (bell-shaped). Seedling age rarely exceeded 15 years. Seedlings grew slowly in the understory, often reaching only 25 cm in height after 8–10 years, and were intensively browsed by deer. Naturally regenerated seedlings were virtually absent from clearcuts, probably because of dense competing vegetation and lack of seed caused by poor dispersal and seed predation. The "window" for the most successful establishment of bigleaf maple seedlings appears to begin after canopy thinning and end before forbs and shrubs invade.

A field experiment informs expected patterns of conifer regeneration after disturbance under changing climate conditions

2015 ◽  
Vol 45 (11) ◽  
pp. 1607-1616 ◽  
Author(s):  
Monica T. Rother ◽  
Thomas T. Veblen ◽  
Luke G. Furman
Keyword(s):  
Field Experiment ◽  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Douglas Fir ◽  
Tree Regeneration ◽  
Colorado Front Range ◽  
Front Range ◽  
Average Growth ◽  
Growth And Survival ◽  
Treatment Type

Climate change may inhibit tree regeneration following disturbances such as wildfire, altering post-disturbance vegetation trajectories. We implemented a field experiment to examine the effects of manipulations of temperature and water on ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings planted in a low-elevation, recently disturbed setting of the Colorado Front Range. We implemented four treatments: warmed only (Wm), watered only (Wt), warmed and watered (WmWt), and control (Co). We found that measures of growth and survival varied significantly by treatment type. Average growth and survival was highest in the Wt plots, followed by the Co, WmWt, and Wm plots, respectively. This general trend was observed for both conifer species, although average growth and survival was generally higher in ponderosa pine than in Douglas-fir. Our findings suggest that warming temperatures and associated drought are likely to inhibit post-disturbance regeneration of ponderosa pine and Douglas-fir in low-elevation forests of the Colorado Front Range and that future vegetation composition and structure may differ notably from historic patterns in some areas. Our findings are relevant to other forested ecosystems in which a warming climate may similarly inhibit regeneration by dominant tree species.

Relationship of Pacific Madrone Sprout Growth to Productivity of Douglas-Fir Seedlings and Understory Vegetation

1990 ◽  
Vol 5 (1) ◽  
pp. 20-24 ◽  
Author(s):  
Thomas F. Hughes ◽  
John C. Tappeiner ◽  
Michael Newton
Keyword(s):  
Pseudotsuga Menziesii ◽  
Secondary Succession ◽  
Douglas Fir ◽  
Understory Vegetation ◽  
Diameter Growth ◽  
Area Index ◽  
Old West ◽  
Pacific Madrone ◽  
Relationship Of ◽  
Sprout Growth

Abstract We studied the development of Pacific madrone (Arbutus menziesii) sprout clumps of various initial densities and their effect on Douglas-fir (Pseudotsuga menziesii) seedling growth and understory vegetation. Five years after density treatments, average leaf area index (LAI) of 9-year-oldmadrone sprouts ranged from 3.6-1.0 m²/m² and total aboveground biomass from 25,630-8,390 kg/ha on the high- and low-density plots, respectively. Diameter of 9-year-old Douglas-fir was inversely related to madrone LAI and ranged from about 27 mm on the high-density plots to 54 mmin the absence of madrone. Analyses of diameter growth trends also indicated that, in the absence of madrone, Douglas-fir grew significantly (P = 0.001 to 0.023) faster than in other treatments. An index of shrub, forb, and grass density was inversely related to madrone LAI, suggesting thatunderstory species are quickly excluded from young madrone stands during secondary succession. We provide equations relating the 5-year growth of 9-year-old Douglas-fir to measures of madrone density and seedling size made when the plantation was 5 years old. West. J. Appl. For. 5(1):20-24.

COMPARISON OF INSECT FAUNA CAPTURED IN SIX DIFFERENT TRAP TYPES IN A DOUGLAS-FIR FOREST

1987 ◽  
Vol 119 (12) ◽  
pp. 1101-1108 ◽  
Author(s):  
Christopher L. Canaday
Keyword(s):  
Tree Species ◽  
Survey Methods ◽  
Douglas Fir ◽  
Insect Fauna ◽  
Acer Macrophyllum ◽  
Live Oak ◽  
Lithocarpus Densiflorus ◽  
Trap Location ◽  
Pacific Madrone ◽  
The Given

AbstractInsects were sampled in a Douglas-fir forest in California to evaluate differences among inexpensive survey methods. Sampling was done with sweep nets and with window, sticky, light, suspended cone, and two kinds of yellow pan traps. Also examined were effects of trap location in the given tree and the following tree species: Douglas-fir (Pseudotsuga menziesii Franco), canyon live oak (Quercus chrysolepis Liebm.), tanoak (Lithocarpus densiflorus Rehd.), Pacific madrone (Arbutus menziesii Pursh.), and big-leaf maple (Acer macrophyllum Pursh.). Relative abundance and faunistic similarity of the 9662 insects caught varied greatly by trap type and little by tree species or trap location. Family-level taxonomic richness differed among the diverse trap types, tree species, and trap locations.

Douglas Fir Release from Tanoak and Pacific Madrone Competition

Weed Science ◽  
1976 ◽  
Vol 24 (1) ◽  
pp. 144-145 ◽  
Author(s):  
S. R. Radosevich ◽  
P. C. Passof ◽  
O. A. Leonard
Keyword(s):  
Acetic Acid ◽  
Douglas Fir ◽  
Coast Range ◽  
Oregon Coast Range ◽  
Burned Areas ◽  
Lithocarpus Densiflorus ◽  
Pacific Madrone ◽  
Broadleaf Species ◽  
Southwest Oregon ◽  
Dichlorophenoxy Acetic Acid

Broadleaf species such as tanoak [Lithocarpus densiflorus (Hook. & Arn.) Rend.] and pacific madrone (Arbutus menziezii Pursh) reduced conifer growth on previously logged or burned areas of the northern California and southwest Oregon coast range. Cut-surface applications of 2,4-D [(2,4-dichlorophenoxy)acetic acid], 2,4,5-T [(2,4,5-trichlorophenoxy)acetic acid], and picloram (4-amino-3,5,6-trichloropicolinic acid) into tanoak and pacific madrone growing as overstory to Douglas fir [Pseudotsuga menziesii (Mirb.) Franco] were found to provide acceptable control for 10 years following application. Increment cores obtained from Douglas fir in treated and non-treated plots revealed substantial stem enlargement as a result of tanoak and pacific madrone control.

Growth response of unthinned and thinned Douglas-fir stands to single and multiple applications of nitrogen

1990 ◽  
Vol 20 (3) ◽  
pp. 343-349 ◽  
Author(s):  
K. A. Stegemoeller ◽  
H. N. Chappell
Keyword(s):  
Growth Response ◽  
Regional Scale ◽  
Volume Growth ◽  
Basal Area ◽  
Douglas Fir ◽  
Untreated Plot ◽  
Growth Responses ◽  
Average Growth ◽  
Duration Of Response ◽  
And Control

Basal area and volume growth response of unthinned and thinned Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stands to single and multiple applications of nitrogen fertilizer were estimated for eight 2-year periods. Response estimates, as differences between growth rates on fertilized and control plots after adjusting for initial volume (or basal area), and trends were analyzed on a regional scale. Average responses to the initial fertilization and to both the second and third fertilizer applications, 8 and 12 years later, were statistically significant (p < 0.05). In thinned stands, average duration of response to the initial treatment was approximately 8 years; unthinned stands continued to show significant volume growth response through 14 years, although basal area growth response decreased to nonsignificant levels between years 10 and 12. In both cases, the response to refertilization, while significant, was smaller than the response to the initial fertilization. Nitrogen applied after the 8th year, and a refertilization after the 12th, on one initially untreated plot at each installation also produced significant average growth responses.

Influence of vegetation type and madrone soil inoculum on associative nitrogen fixation in Douglas-fir rhizospheres

1990 ◽  
Vol 20 (3) ◽  
pp. 368-371 ◽  
Author(s):  
M. P. Amaranthus ◽  
C. Y. Li ◽  
D. A. Perry
Keyword(s):  
Acetylene Reduction ◽  
Mycorrhizal Fungi ◽  
Nitrogenase Activity ◽  
Vegetation Type ◽  
Douglas Fir ◽  
Plant Soil ◽  
Soil Systems ◽  
Whole Plant ◽  
Pacific Madrone ◽  
A Site

Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings grown on a site cleared of whiteleaf manzanita (Arctostaphylosviscida Parry) and an adjacent, cleared, annual grass meadow were either inoculated with 100–120 mL per seedling of pasteurized or unpasteurized soil from a nearby Pacific madrone (Arbutusmenziesii Pursh) stand or left uninoculated. After one growing season, Douglas-fir seedling whole-plant soil systems were assayed for nitrogenase activity by the acetylene reduction method. The rate of acetylene reduction in rhizospheres of uninoculated seedlings from the manzanita site (1.40 ± 0.44 nmol•h−1) was significantly higher than that of uninoculated seedlings from the meadow site (0.67 ± 0.15 nmol•h−1). Unpasteurized madrone soil increased the rate of acetylene reduction over 500% for inoculated seedlings grown on the manzanita site, but decreased it by 80% for those grown on the meadow site. The madrone soil influence was apparently biotic: pasteurized, madrone soil did not have a significant effect. No acetylene was reduced in soil without seedlings. Azospirillum sp., a microaerophilic nitrogen (N2) fixing bacterium, was isolated from within the mycorrhizae of inoculated seedlings harvested from the manzanita site. These results suggest that early successional ectomycorrhizal shrubs and hardwood trees may be important in maintaining mycorrhizal fungi and associated N2 fixers after severe disturbance.

Estimating seed crops of conifer and hardwood species

1992 ◽  
Vol 22 (6) ◽  
pp. 832-838 ◽  
Author(s):  
Philip M. McDonald
Keyword(s):  
Ponderosa Pine ◽  
Douglas Fir ◽  
Rating System ◽  
Visual Rating ◽  
Seed Crop ◽  
Hardwood Species ◽  
Sugar Pine ◽  
Pacific Madrone ◽  
Total Seed ◽  
Seed Crops

Cone, acorn, and berry crops of ponderosa pine (Pinusponderosa Dougl. ex Laws. var. ponderosa), sugar pine (Pinuslambertiana Dougl.), Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), California white fir (Abiesconcolor var. lowiana (Gord.) Lemm.), incense-cedar (Libocedrusdecurrens Torr.), California black oak (Quercuskelloggii Newb.), tan oak (Lithocarpusdensiflorus (Hook. & Arn.) Rehd.), and Pacific madrone (Arbutusmenziesii Pursh) were evaluated over a 24-year period (1958–1981) from an area in northern California by an easy to use visual crop rating system. Seed-trap data, also for 24 years, were gathered for four conifer species. Together, these data provide the wild-land manager with knowledge on seed-crop quantity, quality, and timing. The visual rating system involves visually estimating the amount of fruit in trees and the proportion of trees with fruit, and ranking the crop by species. Regressions of sound seed and total seed on seed-crop rating are provided for the two species with the most seed crops: ponderosa pine and Douglas-fir. Regressions were significant at the 1% level, and coefficients of determination ranged from 0.58 to 0.76.

Sign in / Sign up

Export Citation Format

Share Document