1. Belz, D. and T.E. Nishimura.
1989. Effects of imazapyr, 2,4-D
and metsulfuron methyl on conifer tolerance.
Proceedings-of-the-Western-Society-of-Weed-Science (Vol. 42): 98-104.
Keywords: site preparation
chemical preparation
release treatments
chemical release
tree/stand health
Abstract: Imazapyr at
0.25-1.0 lb/acre alone or 0.5 lb/acre in combination with 2,4-D
2 lb/acre or metsulfuron 0.3 lb/acre was evaluated
for effect on growth and injury to Pseudotsuga menziesii, Pinus ponderosa, Tsuga heterophylla and Abies amabilis seedlings in the
2. Brandeis, T.J., M. Newton and E.C.
Cole. 2001. Underplanted conifer seedling survival
and growth in thinned Douglas-fir stands. Canadian-Journal-of-Forest-Research
31(2): 302-312.
Keywords: planting operations
thinning
commercial thinning
site preparation
chemical preparation
release treatments
chemical release
growth
tree/stand health
regeneration
Abstract: In a
multilevel study conducted at the Oregon State University's McDonald-Dunn
Research Forest, Oregon, USA, to determine limits to underplanted
conifer seedling growth, Douglas-fir (Pseudotsuga menziesii), grand fir (Abies grandis), western redcedar (Thuja plicata) and western
hemlock (Tsuga heterophylla)
seedlings were planted in January 1993 beneath second-growth Douglas-fir stands
that had been thinned in 1992 to basal areas ranging from 16 to 31 m2/ha. Understorey vegetation was treated with a broadcast
herbicide (glyphosate + imazapyr)
application prior to thinning, a directed release herbicide (glyphosate, plus triclopyr for
tolerant woody stems) application 2 years later, or no treatment beyond harvest
disturbance. Residual overstorey density was
negatively correlated with percent survival for all four species. Broadcast herbicide
application improved survival of grand fir and western hemlock. Western redcedar, grand fir and western hemlock stem volumes were
inversely related to overstorey tree density and this
effect increased over time. There was a strong indication that this was also
the case for Douglas-fir. Reduction of competing understorey
vegetation resulted in larger fourth-year stem volumes in grand fir and western
hemlock.
3. Brandeis, T.J., M. Newton and E.C.
Cole. 2002. Biotic injuries on conifer seedlings planted in forest understory environments. New Forests 24:1-14.
Keywords: planting operations
site preparation
chemical preparation
release treatments
chemical release
thinning
tree/stand protection
growth
tree/stand health
Abstract: The effects
of partial overstorey retention, understorey
vegetation management, and protective Vexar(R) tubing
on the frequency and severity of biotic injuries in a two-storied stand underplanted with western redcedar
(Thuja plicata),
Douglas-fir (Pseudotsuga menziesii),
grand fir (Abies grandis),
and western hemlock (Tsuga heterophylla)
were investigated. The most prevalent source of damage was browsing by
black-tailed deer (Odocoileus hemionis
columbiana); deer browsed over 74% of Douglas-fir and
over 36% of western redcedar seedlings one or more
times over the four years of this study. Neither the spatial pattern of
thinning (even or uneven) nor the density of residual overstorey
affected browsing frequency. Spraying subplots may have slightly increased
browsing frequency, but the resulting reduction of the adjacent understorey vegetation increased the volume of all
seedlings by 13%, whether or not they were browsed. Vexar(R)
tubing did not substantially affect seedling survival, browsing damage
frequency, or fourth-year volume. Greater levels of overstorey
retention reduced frequency of second flushing. Chafing by deer and girdling by
rodents and other small mammals began once seedlings surpassed 1 m in height.
Essentially all grand fir seedlings exhibited a foliar fungus infection.
4. Busse,
M.D., G.O. Fiddler and A.W. Ratcliff. 2004. Ectomycorrhizal
formation in herbicide-treated soils of differing clay and organic matter
content. Water, Air, and Soil Pollution 152:23-34.
Keywords: release treatments
chemical release
growth
tree morphology
tree/stand health
soil properties
mycorrhizal response
Abstract: Herbicides
are commonly used on private timberlands in the western
5. Cole, E.C. and M. Newton. 1987.
Fifth-year response of Douglas-fir to crowding and nonconiferous
competition. Canadian-Journal-of-Forest-Research 17(2): 181-186.
Keywords: release treatments
chemical release
growth
tree morphology
Abstract: Measurements
were made in autumn 1982 in 5-yr-old plantations with trees spaced 17-123 cm
apart, alone or with grass or red alder (Alnus rubra) on 3 site types in the
6. Cole, E.C. and M. Newton. 1989a.
Height growth response in Christmas trees to sulfometuron
and other herbicides. Proceedings-of-the-Western-Society-of-Weed-Science (Vol.
42): 129-135.
Keywords: release treatments
chemical release
growth
tree/stand health
stand conditions
Abstract: Abies procera, A. grandis and Pseudotsuga menziesii cv. Menziesii were evaluated for
tolerance to sulfometuron (0.05-0.21 kg/ha), atrazine (4.5 kg/ha) and hexazinone
(2.2 kg/ha). Herbicides were applied pre-budbreak and
sulfometuron was also applied post-budbreak. Weeds were suppressed equally effectively by all
rates and herbicides pre-em. Low rates of sulfometuron were less effective post-em.
There was no significant damage to A. procera
seedlings, although the highest rate of sulfometuron
slowed growth significantly. A. grandis was not
affected by any treatment. All treatments caused injury to 1-year-old P. menziesii, primarily needle chlorosis
and slight stunting. Growth was best in atrazine-treated
plots. For 3-year-old P. menziesii, injury was not
significant but high rates of sulfometuron caused
cosmetic damage. Best growth was observed with hexazinone
and worst with sulfometuron. Post-budbreak
applications and high rates of sulfometuron reduced
growth more than pre-budbreak application and low
rates.
7. Cole, E.C. and M. Newton. 1989b. Seasonal efficacy comparison of two glyphosate
formulations. Proceedings-of-the-Western-Society-of-Weed-Science (Vol.
42): 136-142.
Keywords: release treatments
chemical release
tree/stand health
stand conditions
Abstract: Glyphosate formulations with 13% (Roundup) and without
(Accord) surfactant were compared at 0.84 and 1.68 kg/ha, applied June-Oct.
against Alnus rubra, Rubus spectabilis, R. parviflorus, R. ursinus and Pteridium aquilinum in a Pseudotsuga menziesii cv. menziesii
plantation. No differences in efficacy between the two formulations against any
species were noted. All species were controlled better by high rates of
herbicide. R. spectabilis and R. parviflorus
were controlled <less or =>100%, although July applications were least
effective. A. rubra was reduced <less or =>80%
and early application gave best control. Rates of application had less effect
on Pteridium aquilinum
control (<less or =>98%), and Oct. applications were least effective.
Damage to Pseudotsuga menziesii
was worst with June applications and decreased through the year. Oct. treatment
caused negligible damage.
8. Cole, E.C., M. Newton and D.E.
White. 1986. Response of northwestern hardwoods, shrubs, and Douglas-fir to
Arsenal and Escort. Proceedings-of-the-Western-Society-of-Weed-Science
(Vol.39): 93-101.
Keywords: release treatments
chemical release
tree/stand health
stand conditions
Abstract: Arsenal
(imazapyr) and DPX-T6376 (metsulfuron)
were evaluated for scrub control in Pseudotsuga menziesii plantations at 3 sites in
9. Cole, E.C., M. Newton and D.E.
White. 1988. Efficacy of imazapyr and metsulfuron methyl for site preparation and conifer release
in the
Keywords: release treatments
chemical release
tree/stand health
stand conditions
Abstract: Imazapyr (Arsenal)
and metsulfuron methyl (Escort) were tested at 3
rates for controlling shrubs in young Douglas fir (Pseudotsuga
menziesii) plantations on 3 sites in the
10. Dimock,
E.J., II and E.B. Collard. 1981. Postplanting sprays
of dalapon and atrazine to
aid conifer establishment. Pacific-Northwest-Forest-and-Range-Experiment-Station,-USDA-
Keywords: release treatments
chemical release
growth
tree/stand health
stand conditions
Abstract: A
mixture of dalapon and atrazine
at 8 and 4 lb/acre, respectively, or dalapon or atrazine alone were applied to control perennial grasses
and forbs competing with newly planted seedlings of ponderosa pine and Douglas
fir. In 4 studies in
11. Figueroa, P.F. 1989. Bigleaf maple control: triclopyr
thin-line and spot-foliar application treatments using imazapyr,
metsulfuron, and glyphosate.
Proceedings-of-the-Western-Society-of-Weed-Science (Vol. 42): 104-119.
Keywords: release treatments
chemical release
stand conditions
economics
Abstract: Field
trials were conducted to compare the efficacies of March applications of triclopyr thin-line +or- 1 kg/ha Mor-act
or 2,4-D (1:1) with June spot-foliar applications of
0.6 or 1.1 kg/ha imazapyr, 0.170 kg/ha metsulfuron and 6.7 kg/ha glyphosate
to control Acer macrophyllum in a Pseudotsuga
menziesii plantation. All thin-line treatments gave
80% control 2 years later; complete sanding was hindered by stems growing along
the ground. Dilution did not affect control. Spot-application success depended
on degree of crown coverage. metsulfuron
and glyphosate were not effective, but imazapyr control reached 60-70% 2 years after treatment.
Only triclopyr and full coverage imazapyr
suppressed A. macrophyllum growth to below the height
of P. menziesii. Crown volume was held to
pre-treatment levels with metsulfuron and glyphosate but decreased with imazapyr.
The two treatment methods tested are potentially cost-effective; triclopyr costs are higher but spot-application carries
higher labour costs. Application rates of 2 ml triclopyr/ Msuperscript 2 crown
area will give 100% control if all stems are banded; with delivery rates of 59
ml/clump a 45% solution can be used.
12. Figueroa, P.F. 1991. Ground
applied herbicide methods for red alder control: herbicide efficacy, labor
costs, and treatment method efficiency. In Proceedings-of-the-Western-Society-of-Weed-Science,12-14-March-1991. pp. 44: 53-68.
Keywords: release treatments
chemical release
economics
stand conditions
Abstract: A study
was conducted to develop the cost estimates for ground-applied manual control
methods in variable density red alder [Alnus rubra] stands and to evaluate the efficacy of the various
herbicide formulations for each system. Field trials were initiated in 3
Douglas fir [Pseudotsuga menziesii]
plantations located on Weyerhaeuser Company land located in
13. Figueroa, P.F. 1993. Efficacy and
cost of ground-applied herbicide methods for red alder control. Down to Earth
48(1): 6-10.
Keywords: release treatments
chemical release
stand conditions
growth
tree/stand health
Abstract: The
effects on red alder [Alnus rubra]
mortality, diam. at breast height and height, and any
phytotoxic effects to Douglas fir [Pseudotsuga menziesii] of Garlon 4 (triclopyr) at 4
lb/gallon and Chopper EC (imazapyr) at 2 lb, applied
by stream line, thin line and low vol. treatments, and of Garlon
3A (triclopyr) at 3 lb, Roundup (glyphosate)
at 3 lb and Arsenal (imazapyr) at 4 lb applied by cut
stump treatment were evaluated in streamside buffer zones in two 6-year-old P. menziesii plantations in SW Washington. All treatments
resulted in good control of A. rubra, but the most
cost-effective control was achieved by the stream line application of Garlon 4, followed by low vol. basal or thin line
treatments of Garlon 4 and cut stump treatment with
50% Garlon 3, 45% Roundup and 10% Arsenal. Negligible
P. menziesii damage was caused by cut stump
treatments, but damage occurred with basal-bark treatments although Garlon 4 generally caused less injury than Chopper EC.
14. Figueroa, P.F. and V.F. Carrithers. 1993. Bigleaf maple
control: thinline basal applications using triclopyr and triclopyr plus picloram. In Proceedings-of-the-Western-Society-of-Weed-Science,
9-11-March-1993. pp. 46: 24-30.
Keywords: release treatments
chemical release
stand conditions
economics
Abstract: A field
trial was conducted at Mt. St. Helens Tree Farm, Cowlitz county, Washington, in
1988-91 to determine the min. threshold level of herbicide needed to control bigleaf maple [Acer macrophyllum]
stump sprouts in Douglas fir [Pseudotsuga menziesii]. Garlon (triclopyr) at 0.24-3 lb/gal was applied on
15. Figueroa, P.F., R.C. Heald and S.R. Radosevich. 1990.
Sensitivity of actively growing Douglas-fir to selected herbicide formulations.
Proceedings-of-the-Western-Society-of-Weed-Science 43: 45-52.
Keywords: release treatments
chemical release
growth
tree/stand health
Abstract: The
results of field studies at 2 sites in Washington and California indicated that
aerial spraying of 2,4-D at 4 lb/acre, triclopyr ester at 4 lb/acre or 2,4-D + triclopyr
ester at 1.2 lb/acre + 0.5 lb/acre to control red alder [Alnus
rubra] led to a significant reduction in Douglas fir
[Pseudotsuga menziesii]
growth and survival if applied during periods of active conifer growth.
Herbicides applied singly at high rates caused significantly more mortality
than the herbicides in combination. At both sites, trees had not fully
recovered 5 and 6 years after treatment; damaged trees were at least 1 year
behind untreated trees in growth.
16. Fischer, V.F. and V.F. Carrithers. 1992. Tolerance of one and two year old douglas-fir seedlings to triclopyr
applications. In
Proceedings-of-the-Western-Society-of-Weed-Science, 10-12-March-1992.
Keywords: release treatments
chemical release
tree/stand health
Abstract: In
field trials conducted near
17.
Keywords: release treatments
chemical release
manual release
growth
soil properties
Abstract: Harsh
environments on many harvested sites in
18. Gourley,
M., M. Vomocil and M. Newton.
Keywords: release treatments
chemical release
tree/stand protection
growth
tree/stand health
Abstract: In January
and February 1981, three-year-old bare-root Douglas fir (Pseudotsuga
menziesii) transplants were established in four
clear-felled locations in the
19. Haight,
R.G. 1993a. The economics of Douglas-fir and red alder
management with stochastic price trends.
Canadian-Journal-of-Forest-Research 23(8): 1695-1703.
Keywords: planting operations
site preparation
prescribed fire
release treatments
chemical release
thinning
precommercial thinning
commercial thinning
tree/stand protection
economics
Abstract: A
financial analysis of Douglas fir (Pseudotsuga menziesii) and red alder (Alnus rubra) management was conducted using yield projections
from the Stand Projection Simulator for the
20. Haight,
R.G. 1993b. Technology change and the economics of silvicultural investment.
Rocky-Mountain-Forest-and-Range-Experiment-Station,-USDA-
Keywords: planting operations
site preparation
prescribed fire
release treatments
chemical release
tree/stand protection
thinning
commercial thinning
precommercial thinning
yield
economics
Abstract: Financial
analyses of intensive and low-cost reforestation options are conducted for loblolly
pine (Pinus contorta)
stands with broadleaved competition in the Southern USA, and Douglas fir with
red alder (Pseudotsuga menziesii
with Alnus rubra) in the
Pacific Northwest. Results show that the expected present values (EPVs) of low-cost options that result in mixtures of
conifers and broadleaves are superior in some situations to the EPVs of the intensive options.
21. Harrington, T.B., R.G. Wagner,
S.R. Radosevich and J.D. Walstad.
1995. Interspecific competition and herbicide injury
influence 10-year responses of coastal Douglas-fir and associated vegetation to
release treatments. Forest-Ecology-and-Management 76(1/3): 55-67.
Keywords: release treatments
chemical release
manual release
growth
tree/stand health
tree physiology
stand conditions
Abstract:
Responses of competing vegetation and planted Douglas fir (Pseudotsuga
menziesii var. menziesii)
were studied for 10 years after six herbicide and manual release treatments in
the Washington and Oregon Coast Ranges. Studies were installed in six 2- or
3-yr-old plantations, with Douglas fir densities of 988 to 1482 plants/ha at
time of planting and 721 to 1282/ha 2 to 3 years late. Research objectives were
to quantify regional, long-term responses of vegetation (Douglas fir and
non-coniferous species) to various levels of competition, light and soil water
availability, and intensity versus importance of factors influencing Douglas
fir growth. Three treatments reduced shrub cover relative to the untreated
check: triclopyr in year 1, glyphosate
in years 1-5, and repeated control (via several herbicide applications) in
years 1-10. Reductions in woody cover from glyphosate
stimulated increases in herb cover in years 3 and 5, while repeated control
reduced herb cover in years 1, 2 and 5. Through year 10, Douglas fir survival
(86-99%) varied little among treatments. Visual symptoms of herbicide injury to
Douglas fir from triclopyr (45% of trees) and glyphosate (17% of trees) were associated with 0.1-0.2 m
reductions in first-year height. After adjusting for tree size, Douglas fir
growth in stem basal area 2 years after triclopyr was
less than that of the untreated check, suggesting prolonged effects of
herbicide injury. Because it sustained low levels of interspecific
competition, caused minimal tree injury, and prevented overtopping cover from
red alder (Alnus rubra),
repeated control was the only treatment in which Douglas fir size (9.8 m height
and 21 cm basal diameter in year 10) significantly exceeded (P<less or
=>0.02) that of the untreated check (7.8 m height and 12 cm diameter).
22. Helgerson,
O.T. 1990b. Response of underplanted
Douglas-fir to herbicide injection of sclerophyll
hardwoods in southwest
Keywords: nursery operations
release treatments
chemical release
stand conditions
tree physiology
tree/stand health
growth
Abstract:
Low-value broadleaf sclerophyll forests in
23. Kelpsas,
B.R. 1987. Seasonal impacts of fluroxypyr and triclopyr on conifers and shrubs.
Proceedings-of-the-Western-Society-of-Weed-Science (Vol.40): 128-129.
Keywords: release treatments
chemical release
tree/stand health
stand conditions
Abstract: Release
of Pseudotsuga menziesii
from Rubus spectabilis and Alnus rubra in a plantation in
the
24. Ketchum, J.S., R. Rose and B. Kelpsas. 2000. Comparison of adjuvants
used in fall-release herbicide mixtures for forest site preparation.
Tree-Planters' Notes 49(3): 66-71.
Keywords: site preparation
chemical preparation
release treatments
chemical release
tree/stand health
stand conditions
Abstract: Tank
mixes of the herbicides imazapyr and glyphosate were applied at 3 rates with 3 adjuvants (LI-700Reg., Nu-Film-IRReg.,
Silwet L-77Reg.) over
25. Knapp, W.H., T.C. Turpin and J.H.
Beuter. 1984. Vegetation control for Douglas-fir
regeneration on the
Keywords: planting operations
site preparation
chemical preparation
mechanical preparation
prescribed fire
release treatments
chemical release
manual release
growth
yield
economics
Abstract: Records
from 324 plantations in
26.
Keywords: release treatments
chemical release
manual release
growth
tree morphology
Abstract: Height-age
and height-diameter models for plantations of young Douglas fir (Pseudotsuga menziesii var. menziesii) were examined in relation to vegetation
management treatments. The models were developed from 10 years of measurements
in a competition release study installed on six sites in the Coast Ranges of
Oregon and Washington. Analysis of height growth patterns for dominant trees
indicated significant differences between the total vegetation control
treatment and operational release treatments or no treatment. The resulting
height-age function depicted exponential growth patterns for the total
vegetation control treatment and nearly linear patterns for the operational
release treatment and no treatment. The height-diameter function was compatible
with dominant height growth and quadratic mean diameter prediction functions.
Different height-diameter curve shapes were associated with total vegetation
control and the operational release and no treatments. The resulting function
implied that Douglas fir trees of a given diameter and age were slightly taller
when under interspecific competition, especially for
trees with smaller diameters. The height-age and height-diameter functions may
be used in conjunction with diameter distribution or stand table projection
models developed for these data to predict dynamics and stand structure in
young Douglas fir plantations.
27.
Keywords: release treatments
chemical release
growth
tree morphology
Abstract: A stand
table projection system based on individual-tree and stand-level models for
young Douglas fir (Pseudotsuga menziesii
var. menziesii) plantations was developed from and
evaluated with remeasurement data from xeric sites in
the Siskiyou Mountains of SW Oregon (established in a competition gradient
study), and mesic sites in the Coast Ranges of Oregon
and Washington (established in a treatment efficacy study). A projection
equation was developed for relative tree size, defined as the ratio of
individual-tree diameter at 15 or 30 cm above ground level (depending on the
study location) to quadratic mean diameter. The relative size projection
equation for the
28.
Keywords: release treatments
manual release
chemical release
growth
tree morphology
Abstract: A parameter
recovery procedure for the Weibull distribution
function, based on diameter percentiles, was modified to incorporate the
effects of competing vegetation in young Douglas fir (Pseudotsuga
menziesii var. menziesii)
plantations. The procedure was tested using data from sites in the Coast Ranges
of Oregon and Washington and in the
29. McDonald, P.M. and G.O. Fiddler.
1993. Feasibility of alternatives to herbicides in young conifer plantations in
Keywords: genetic tree improvement
site preparation
prescribed fire
release treatments
manual release
chemical release
growth
economics
Abstract: A
research programme (involving 40 studies) was started
in 1980 to compare the effectiveness and cost of various vegetation management
techniques used for enhancing growth of 1- to 3-yr-old conifer (Pseudotsuga menziesii, Pinus ponderosa, P. jeffreyi, Abies magnifica and A. concolor var. lowiana)
plantations in California. The studies were ended after 10 yr when competition
became intraspecific. The techniques used included
direct methods such as manual manipulation, mulching, herbicides (Garlon 3A [triclopyr], 2,4-D or Velpar [hexazinone]), and grazing
for releasing conifer seedlings from undesirable vegetation, and several silvicultural practices (broadcast burning, group
selection, genetically improved seedlings) that serve as indirect methods for
reducing or avoiding vegetation problems. Manual release and mulching were
effective but expensive. Herbicides were effective, applicable to almost all
plant communities, and relatively inexpensive. Grazing was good for cattle and
sheep, but did not significantly enhance conifer seedling growth. Silvicultural control of weeds was promising, but there was
not enough information to evaluate feasibility. It was concluded that in most
instances, forests cannot be managed economically without herbicides, if the
objective is to grow seedlings at the potential of the site and the plant
community includes sprouting broadleaves and shrubs or rhizomatous forbs and
ferns. If the objective is to create a forest with several age-classes and variable
structure, but with slower seedling growth, longer rotations, and less species
diversity in early seral stages, then it is possible
to accomplish this using other vegetation management techniques.
30. McDonald, P.M. and G.O. Fiddler.
1996. Development of a mixed shrub-tanoak-Douglas-fir community in a treated
and untreated condition. Pacific-Southwest-Research-Station,
USDA-Forest-Service Research-Paper PSW-RP-225. iv
+ 16 p.
Keywords: release treatments
manual release
chemical release
tree/stand health
growth
tree morphology
stand conditions
economics
Abstract: On a
medium site in northern California, a tanoak (Lithocarpus
densiflorus)-mixed shrub community in a Douglas fir
plantation was given several treatments (manual release two and three times, a
combination chainsaw and cut surface herbicide (Garlon
3A [triclopyr]) treatment, two foliar herbicides (2,4-D or Garlon 4), and a tank mix
of the two herbicides) to study its development in both a natural (control) and
treated condition. The herbicides were each applied twice. Survival of planted
Douglas fir (Pseudotsuga menziesii)
seedlings was recorded for 11 years and growth was quantified for 9 years after
the last treatment application. In addition to Douglas fir, data are presented
individually for the two most abundant species (tanoak and snowbrush, Ceanothus velutinus var. hookeri), for greenleaf manzanita (Arctostaphylos patula), and for the hardwood tree and shrubs combined. At
the study's end in 1992, combined vegetation in the control had a mean density
of 1800 plants/acre, foliar cover of 23 700 ftsuperscript 2/acre, and height of 11.2 ft. In
contrast, combined tree and shrubs in the most effective treatment for
controlling them (cut and spray Garlon 3A) had a mean
density of 150 plants/acre, foliar cover of 150 ftsuperscript 2/acre and height of 5.9 ft at study
end. Because competition for site resources was low, Douglas fir seedlings
developed best in this treatment. Mean Douglas fir diameter was 4.6 inches at
12 inches above mean ground line, height averaged more than 21 ft, and mean
foliar cover was 39 850 ftsuperscript 2 at the end of
the study. The cost was $227 per acre.
31. McDonald, P.M. and G.O. Fiddler.
1999. Ecology and development of Douglas-fir seedlings and associated plant species
in a
Keywords: release treatments
manual release
chemical release
stand conditions
growth
tree morphology
economics
Abstract: On an
average site in northern coastal California, USA, a tanoak (Lithocarpus
densiflorus)-mixed shrub community was given several
treatments (manual release one, two, and three times; a combination chainsaw
and cut surface chemical treatment; two foliar chemicals; and a tank mix of the
two chemicals) to study its development over an 11-year period (1981-91) in
both a broadcast-burned (untreated control) and released (treated) condition.
The chemicals were 2,4-D, Garlon
[triclopyr] 3A, and Garlon 4,
each applied two times. The site had been planted with 2+0 seedlings of Douglas
fir (Pseudotsuga menziesii)
in 1979. In addition to Douglas-fir , data are
presented individually for the four most abundant and well distributed species
(tanoak, hairy manzanita (Arctostaphylos
columbiana), huckleberries (Vaccinium
ovatum and V. parviflorum),
and rhododendron (Rhododendron macrophyllum)), and
for these plus two more of the tallest and most abundant (but poorly
distributed) species (snowbush (Ceanothus velutinus), elderberry (Sambucus mexicana)) combined. In 1991, combined shrubs in the
control had a mean density of 4733 plants per acre, foliar cover of 16 800 ft2
per acre, and height of 9.5 feet. In contrast, combined shrubs in one of the
most effective treatments for controlling them (2,4-D) had a mean density of
2000 plant per acre, foliar cover of 2600 ft2 per acre and height of 5.5 feet
at the end of the study. Here, mean Douglas-fir diameter was 4.0 inches at 12
inches above mean ground line, height averaged 18.7 feet, and mean foliar cover
was 34 800 ft2 per acre. The cost (including chemical) was $77 per acre. The
biological and economical data in this paper provide the ecosystem manager,
wildlife biologist, and fuels manager with knowledge on how to attain plant
communities with different density and development potentials, and the cost of
creating them.
32. Monleon,
V.J., M. Newton, C. Hooper and J.C. Tappeiner, II. 1999.
Ten-year growth response of young Douglas-fir to
variable density varnishleaf ceanothus
and herb competition. Western-Journal-of-Applied-Forestry 14(4): 208-213.
Keywords: site preparation
chemical preparation
release treatments
chemical release
growth
Abstract: The
effect of different densities of varnishleaf ceanothus (Ceanothus velutinus var. laevigatus) and
herbaceous vegetation control on stem diameter, height, and volume of
Douglas-fir (Pseudotsuga menziesii
var. menziesii) seedlings was examined during the 10
yr following planting on a site near
33.
Keywords: release treatments
chemical release
stand conditions
tree/stand health
Abstract: Field
trials in the
34.
Keywords: release treatments
chemical release
stand conditions
tree/stand health
Abstract: The
effects of 0.5, 1.0 or 1.5 lb a.e. glyphosate/acre as Rodeo or Roundup applied in July or Aug.
at 2 spray vol. with or without surfactant were studied on 5 woody species in
the
35.
Keywords: nursery operations
site preparation
prescribed fire
release treatments
chemical release
growth
tree/stand health
Abstract: Two
long-term experiments in
36.
Keywords: release treatments
chemical release
growth
soil properties
tree physiology
Abstract: Growth
of Douglas fir (P. menziesii) was increased by
controlling grasses and broadleaved weeds with combinations of 4.4 kg atrazine/ha and 2.2 kg 2,4-D or 2,4,5-T during the first 3
years after planting on a well-drained moist site in the Oregon Coast Range.
The greatest growth occurred if weeds were controlled in the same growing
season that tree seedlings were transplanted to the field; smaller increments
came from second- and third-year weed control. Growth increases attributable to
early weed control continued through the fifth year, indicating that conditions
during establishment strongly influenced later growth. Plots with no herbaceous
vegetation had more available soil water than those with competing vegetation,
and tree seedlings on these plots experienced less water stress. Irrigation in
the third year increased stem diameter of seedlings in that year but had no
effect thereafter. Increases in average seedling stem volume at 5 years after
transplanting were linearly related to the difference in observed xylem
potential during the first three seasons after transplanting and the xylem
potential at which photosynthesis ceased, -2 MPa.
37.
Keywords: release treatments
chemical release
growth
tree physiology
soil properties
photosynthesis
Abstract: The
growth of Douglas fir Pseudotsuga menziesii
seedlings was increased during the first 5 years by controlling grasses and
forbs in 7 herbicide regimes during the 1st 3 years, the effect diminishing
with time after planting. Devegetated plots had more
available moisture through the growing season than those with Agrostis tenuis or mixed mixed grass/forb cover dominated
by A. tenuis or Hypochaeris
radicata. Tree moisture stress followed soil moisture
but only after allowing for large fluctuations of diurnal stress. Weed control
relieved moisture stress in trees. P. menziesii
photosynthesis tended to shut down in the region of -2.0 MPa
moisture stress. For the 1st 3 years in a favourable
coastal environment approx. 1700 MPa-h above -2.0 MPa was estimated to be required for survival. Increments
of moisture beyond that would contribute significantly to growth.
38. Petersen, T.D. and M. Newton.
1983. Growth of Douglas-fir following release from snowbrush and forbs in the
Oregon Cascades. Proceedings-of-the-Western-Society-of-Weed-Science (Vol.
36):58-59.
Keywords: release treatments
chemical release
growth
Abstract: Ceanothus velutinus and other weeds such as Epilobium
angustifolium, Rubus ursinus and Pteridium aquilinum suppressed the growth of Douglas fir in
plantations of the central Cascades of W. Oregon. Stem vol. increases of
Douglas fir after 4 yr were greatest when all competing vegetation had been
controlled for 1 growing season with herbicides. It is suggested that C. velutinus competes with Douglas fir by depleting soil moisture
although the cause of competition by other weeds is unknown. The best time for
releasing Douglas fir from competition is discussed.
39. Petersen, T.D., M. Newton and
S.M. Zedaker. 1988. Influence of Ceanothus
velutinus and associated forbs on the water stress
and stemwood production of Douglas-fir.
Forest-Science 34(2): 333-343.
Keywords: release treatments
chemical release
tree physiology
soil properties
growth
Abstract: In
studies in the central Cascade Mts., Oregon, three regimes were established in
1978 around individual trees in four 5-yr-old and four 10-yr-old stands, viz.
no treatment (control), elimination of C. velutinus
with 2,4-D or elimination of C. velutinus and forbs
with 2,4-D and glyphosate. Seasonal and diurnal
variation in stem and soil water potentials were measured during 1979. Soil
water potential during late summer was <-1.5 MPa
at depths of 10, 40 and 100 cm on control plots and at depths of 10 and 40 cm
in 5-yr-old stands and 10 cm in 10-yr-old stands in plots where only C. velutinus was eliminated. In the absence of shrubs and
forbs, soil water potential at 100 cm was near field capacity throughout the
season. Predawn stem water potential during late summer was significantly lower
on control plots than on the treatment plots for all 5-yr-old stands and for
two of the 10-yr-old stands. By 1986, tree stems were 2-6 cm larger in basal diam. and 1-2 m taller in the absence of competitors. The
increase in stem size was greater in the stand treated at 5 yr old than in that
treated at 10 yr old. The correlation between growth and water stress suggests
that interspecific competition for soil water during
summer drought is a limiting factor in stemwood
production.
40. Reynolds, P.E., K. King, R.
Whitehead and T.S. MacKay. 1986. One-year results for a coastal
Keywords: release treatments
chemical release
stand conditions
growth
tree/stand health
Abstract: In
trials on the W. coast of
41. Roberts, S.D.,
Keywords: site preparation
chemical preparation
release treatments
chemical release
soil properties
growth
tree physiology
Abstract: Decisions
made during stand regeneration that affect subsequent levels of competing
vegetation and residual biomass can have important short-term consequences for
early stand growth, and may affect long-term site productivity. Competing
vegetation clearly affects the availability of site resources such as soil
moisture and nutrients. Harvest residues can also affect the availability of
site resources. We examined second and third year seedling performance of a
Douglas fir (Pseudotsuga menziesii)
plantation with different vegetation control and biomass retention treatments
on a highly productive site in the coast range of Washington, USA. Treatments
included a bole-only harvest without vegetation control (BO-VC), a bole-only
harvest with complete vegetation control (BO+VC), and a total tree harvest with
complete vegetation control that also included removal of all coarse woody
debris and harvest residues (TTP+VC). The VC treatment involved: (a) in the
first year, broadcast application of Oust and Accord concentrate applied with a
surfactant 2 weeks before planting; (b) in the second year, a March broadcast
application of Atrazine and a directed spot-spray of
Accord Concentrate on the vegetation between rows in April-May; and (c) in the
third year, a March broadcast application of Atrazine
and Oust, a direct spot-spray application of Accord Concentrate, and a
spot-spray of Transline with surfactant on April-May
to control persistent shrub species. The study was conducted to determine if
vegetation control and residue retention treatments affected soil moisture,
soil temperature, and apparent nitrogen (N) availability, and whether these
differences in site resources were correlated with seedling size and growth. In
both second and third growing seasons, volumetric soil moisture at 0-20 cm
depth was lowest on plots that did not receive vegetation control (BO-VC).
Seedlings on these plots also had the lowest diameter and volume growth. In
year 2, which was fairly moist, volume growth on TTP+VC plots was slightly
higher than on BO+VC plots. TTP+VC plots did have lower soil moisture, but soil
temperatures were slightly warmer. In year 3, a drier year, growth was greatest
on BO+VC plots, which had consistently higher soil moisture levels. Apparent N
availability in year 3 also varied with vegetation control. Douglas fir foliar
N concentrations averaged 2.3% on the plots where competing vegetation was eliminated, compared to 1.8% on plots where competing
vegetation was not controlled. Douglas fir foliar N concentrations did not
differ between residue retention treatments, although N concentrations of
competing vegetation were higher where residual biomass was retained. Higher
apparent N availability was correlated with greater seedling growth. Based on
the results from years 2 and 3, it appears that soil moisture, particularly
late in the growing season, had the greatest effect on seedling growth in both
years. Available N may also have played a role, although the effects of N
cannot be completely separated from those of soil moisture. When soil moisture
is adequate, it appears that available N and soil temperature exert greater
influence on growth. Vegetation control and residue retention can influence all
3 of these factors. The relative importance of each factor may depend on the
year-to-year variation in environmental conditions.
42. Rose, R. and J.S. Ketchum. 1998.
Early results of the 'Herb II' study: evaluating the influence vegetation
control has on fertilization at the time of planting. In Proceedings
of the Annual Meeting of the Western Society of Weed Science, Waikoloa, Hawaii,
10-12 March, 1998. pp. 55-59.
Keywords: release treatments
chemical release
fertilization
growth
Abstract: Field
trials were conducted at 5 sites in the Pacific Northwest region of the USA to
assess the interactive effects between increasing levels of control of deerbrush (Ceanothus integerrimus), snowbrush (C. velutinus),
black cottonwood (Populus trichocarpa),
Scotch broom (Cytisus scoparius),
Portuguese broom (C. striatus), trailing blackberry (Rubus sp.), thimbleberry (R. parviflorus)
and salmonberry (R. spectabilis) with hexazinone or sulfometuron, and
fertilizer treatments using slow release briquettes of N:P:K at 14:3:3 or 9:9:4
applied at planting for Douglas fir (Pseudotsuga menziesii), ponderosa pine (Pinus
ponderosa), western hemlock (Tsuga heterophylla) and coastal redwood (Sequoia sempervirens). Results indicated that at all but one site,
weed control +or- fertilizer led to increased tree growth, while at the fifth
site weed control + fertilizer gave the greatest growth. Fertilizer alone did
not increase growth at any site.
Non-OSU
Link
43. Rose, R. and J.S. Ketchum. 2002.
Interaction of vegetation control and fertilization on conifer species across
the
Keywords: fertilization
release treatments
chemical release
growth
tree/stand health
tree physiology
stand conditions
Abstract: An
experiment evaluating three levels of vegetation competition control (no
control, 1.5 m2 of vegetation control, and 3.3 m2 of vegetation control), each
with two fertilizer application treatments (fertilizer application at the time
of planting with complete slow-release fertilizer (WoodaceReg.
IBDU), or no fertilizer application), was installed at five sites. Two of these
sites were planted with Douglas-fir (Pseudotsuga menziesii) in the Oregon Coast Range, one with ponderosa
pine (Pinus ponderosa) in eastern Washington, one
with western hemlock (Tsuga heterophylla)
in the coastal hemlock zone in Oregon, and one with coastal redwood (Sequoia sempervirens) in northern California, USA. At four of the
five sites, mean stem volume, basal diameter, and height of seedlings increased
significantly with increasing area of weed control, and the magnitude of
difference between treatments increased with time. Fertilizer application
significantly increased seedling size only at the two sites with adequate soil
moisture; increases were marginally significant at a third. Response to
fertilizer application was less than from weed control and impacted growth for
only the first year, whereas the influence of weed control continued to
influence growth the entire length of the study (4 years). Area of vegetation
control and fertilizer application did not interact significantly at any site.
44. Rose, R. and J.S. Ketchum. 2003.
Interaction of initial seedling diameter, fertilization and weed control on
Douglas-fir growth over the first four years after planting.
Annals-of-Forest-Science 60(7): 625-635.
Keywords: nursery operations
fertilization
release treatments
chemical release
growth
tree/stand health
stand conditions
Abstract:
Planting larger stock, fertilizer application and added years of weed control
are often employed to increase growth rate of plantations. We evaluated these
techniques using a replicated factorial study design repeated in two diverse
locations in western
45. Rose, R., J.S. Ketchum and D.E.
Hanson. 1999. Three-year survival and growth of Douglas-fir seedlings under
various vegetation-free regimes. Forest-Science 45(1): 117-126.
Keywords: release treatments
chemical release
growth
tree morphology
tree/stand health
stand conditions
Abstract: Responses
of Douglas-fir (Pseudotsuga menziesii)
seedlings were studied for 3 yr (1993-96) following eight vegetation-control
treatments in three western
46. Roth, B.E. and M. Newton. 1996a. Role of Lammas growth in recovery of Douglas-fir seedlings
from deer browsing, as influenced by weed control, fertilization, and seed
source. Canadian-Journal-of-Forest-Research 26(6): 936-944.
Keywords: planting operations
release treatments
chemical release
fertilization
tree/stand protection
growth
tree/stand health
Abstract: This study
examined the effects of weed control, nitrogen fertilizer, and seed source on
Lammas growth (second flushing) in Douglas fir (Pseudotsuga
menziesii) seedlings on 3 sites in the
47. Roth, B.E. and M. Newton. 1996b. Survival and growth of Douglas-fir relating to weeding,
fertilization, and seed source. Western-Journal-of-Applied-Forestry
11(2): 62-69.
Keywords: planting operations
fertilization
release treatments
chemical release
growth
tree physiology
tree morphology
tree/stand health
Abstract: The goal
of this study was to quantitatively evaluate the individual and interactive
effects of weed control, nitrogen fertilizer, and seed source on Douglas fir (Pseudotsuga menziesii) survival
and growth in plantations on a range of sites and growing conditions in western
48. Stapanian, M.A. and D.W. Shea. 1986. Lignosulfonates: effects on plant growth and survival and
migration through the soil profile.
International-Journal-of-Environmental-Studies 27(2): 45-56.
Keywords: release treatments
chemical release
growth
stand conditions
Abstract: The
effects of a refined lignosulfonate product obtained
from the sulfite pulping process, on growth and survival of plants were
investigated. After applications of 0, 7500, 15 000 and 22 500 cmsuperscript 3/msuperscript 2 to plots within a forest
plantation, the following were monitored: (1) live aboveground biomass of
vascular plants, (2) growth of Douglas fir (Pseudotsuga
menziesii) and (3) lignosulfonate
migration through the soil profile. Biomass of woody vegetation was not
affected, and that of herbaceous plants was significantly decreased only at the
two greatest application rates. Growth of the Douglas fir trees was not
significantly affected. Lignosulfonates disappeared
from the soil profile at the same rate regardless of initial concentration.
Although it is not practical to use this material as a herbicide in western
49. Sumaryono
and G. Crabtree. 1989. Differential tolerance of woody nursery crop seedlings
to napropamide. Weed-Technology 3(4): 584-589.
Keywords: nursery operations
release treatments
chemical release
tree/stand health
Abstract: Field
studies at Corvallis, Oregon and greenhouse experiments were conducted to
evaluate the tolerance to napropamide of black locust
(Robinia pseudoacacia), honeylocust (Gleditsia triacanthos), apple, Douglas fir (Pseudotsuga
menziesii), ponderosa pine (Pinus
ponderosa) and Japanese black pine (Pinus thunbergii) in the seedling stage. Deciduous species were
more susceptible to napropamide than coniferous
species. Apple had the slowest seed germination and root development and was
more susceptible. The deciduous species had more secondary roots in the shallow
soil layer which contained most of the herbicide than the coniferous species.
The roots of all woody species tested in vitro were inhibited significantly by
contact with the herbicide, but only shoot growth of apple and black locust was
inhibited. Injury to woody nursery crop seedlings may be avoided by delaying
herbicide application.
50. Tung, C.H., J. Batdorff and D.R. DeYoe. 1986a. Survival
and growth of Douglas-fir seedlings with spot-spraying, mulching and
root-dipping. Western-Journal-of-Applied-Forestry 1(4): 108-111.
Keywords: nursery operations
release treatments
chemical release
manual release
tree/stand health
growth
Abstract: In
trials near
51. Wagner, R.G. and M.W. Rogozynski. 1994. Controlling sprout clumps of bigleaf maple with herbicides and manual cutting. Western
Journal of Applied Forestry 9(4):118-124.
Keywords: release treatments
chemical release
manual release
stand conditions
Abstract: Trials
were conducted in 5 young Douglas fir (Pseudotsuga menziesii) plantations for controlling bigleaf
maple (Acer macrophyllum) clumps. Herbicides tested
were glyphosate (Roundup), imazapyr
(Arsenal), metsulfuron methyl (Escort), triclopyr amine (Garlon 3A), triclopyr ester (Garlon 4), and 2,4-DP [dichlorprop]
+ 2,4-D (Weedone 170). Four methods of herbicide
application (basal spray, thinline, foliage spray,
and cut-surface) and 3 treatment timings (early foliar, late foliar, and
dormant periods) were tested. Manual cutting alone was also evaluated at each
of the treatment timings. Imazapyr foliage sprays, triclopyr ester thinline, dormant
3% triclopyr ester basal spray, late-foliar 2,4-DP +
2,4-D basal spray, and manual cutting with triclopyr
amine cut-surface application provided the best control among the treatments
tested over the 3 yr of study. Imazapyr foliage
sprays provided the best long-term control by killing most treated clumps. Triclopyr ester thinline
treatments provided the most consistent and effective results among the basal
applications. Stump applications of triclopyr amine
were more effective than manual cutting alone or manual cutting with glyphosate cut-surface application.
52. Walstad, J.D., J.D. Brodie, B.C.
McGinley and
Keywords: release treatments
chemical release
growth
yield
economics
Abstract: Retrospective
analyses were made of 3 Douglas fir plantations (age 12-39 yr) in western
53. White, D.E. and M. Newton. 1983.
Effects of glyphosate and two formulation of hexazinone in young conifer plantations.
Proceedings-of-the-Western-Society-of-Weed-Science (Vol.36): 54-56.
Keywords: release treatments
chemical release
growth
stand conditions
tree/stand health
Abstract: In
April 1979, 1 month after transplanting 3-yr-old Douglas fir (Pseudotsuga menziesii), hexazinone liquid and solid formulations at 0, 1.11, 1.68
or 2.23 kg/ha were applied to the plots separately and in combination with 0 or
0.62 kg glyphosate/ha. There was no significant
difference between formulations of hexazinone in
effect on the herbaceous community which was dominated by Arrhenatherum
elatius, Holcus lanatus, Elymus glaucus and Rubus ursinus. However, addition of glyphosate
increased the mean weed-free condition from 67.25 to 85.1%. At the same time,
in glyphosate-treated plots, mean ht. of 4th yr trees
was 149.9 cm compared with 162.6 cm in hexazinone-only
plots. Survival of 2nd yr trees was also affected.
54. White, D.E. and M. Newton. 1989.
Competitive interactions of whiteleaf manzanita, herbs, Douglas-fir, and ponderosa pine in
southwest
Keywords: release treatments
chemical release
growth
stand conditions
Abstract: Whiteleaf manzanita (Arctostaphylos viscida) was established on 3 sites in
55. White, D.E. and M. Newton. 1990.
Herbaceous weed control in young conifer plantations with formulations of
nitrogen and simazine.
Canadian-Journal-of-Forest-Research 20(11): 1685-1689.
Keywords: release treatments
chemical release
fertilization
stand conditions
tree/stand health
growth
Abstract: Weed
control and second year survival and growth of newly planted 2+0 Douglas fir (Pseudotsuga menziesii) and 2+0
noble fir (Abies procera)
seedlings were measured at 3 sites in Oregon after application of herbicide and
fertilizer in a replicated complete factorial experiment with 4 levels of simazine (0, 2.2, 4.4, 8.8 kg/ha), 3 levels of N (0, 110,
220 kg/ha), 2 types of N (urea prill; urea + trimamino-s-triazine (TST) prill)
and 2 kinds of formulations (co-granular prill of simazine + nitrogen; nitrogen prill
followed by liquid simazine). For the first growing
season, total weed and grass control increased with increasing simazine rates. Total weed control was better when urea +
TST, rather than urea alone, was applied in conjunction with simazine. Formulation and nitrogen rate were not
significant. After plot treatment with 1.1 kg liquid hexazinone/ha
at the beginning of the second growing season, Douglas fir survival decreased
as the rate of urea alone increased; survival decreased with little or no weed
control and remained constant or increased with good weed control as the rate
of urea + TST increased. Noble fir height and diameter, and Douglas fir
diameter, decreased with poor weed control, but increased at least to the
levels of untreated seedlings with good weed control. Noble fir diameter
responded positively to added nitrogen. Although simazine
may be toxic to first year conifers, this study suggests that more complete
weed control in conjunction with fertilization may benefit young conifer
plantations.
56. White, D.E., L. Witherspoon-Joos and M. Newton. 1990. Herbaceous weed control in conifer
plantations with hexazinone and nitrogen
formulations. New-Forests 4(2): 97-105.
Keywords: release treatments
chemical release
fertilization
stand conditions
growth
tree/stand health
Abstract: In
order to determine if herbicide efficacy is affected by nitrogen fertilizer,
and to examine the effects of treatments on growth and survival of
newly-planted 2-year-old Douglas fir (Pseudotsuga menziesii) and 3-year-old noble fir (Abies
procera), the influence of different nitrogen
fertilizers applied in different combinations with hexazinone
formulations were evaluated on three herbaceous weed communities in Oregon.
Field studies comparing three application methods in conifer plantations showed
greatest reduction in total weed cover with a co-granular formulation of hexazinone and the slow-release nitrogen fertilizer triamino-s-triazine (TST). Slightly less control was
achieved with separate applications of liquid hexazinone
and TST granules, and poorest control with granular urea followed by liquid hexazinone. Weed control increased with an increase in hexazinone rate. Statistical analysis of the effect on
conifers showed that the highest hexazinone rate
significantly increased survival of noble fir, stem diameter of both noble fir
and Douglas fir, and that the highest nitrogen rate significantly reduced
survival of both species but did not affect stem diameter. Survival of noble
fir and diameter of both noble fir and Douglas fir were significantly increased
where a co-granular formulation of hexazinone and TST
granules was used.
57. Woods, J.H., D. Kolotelo and A.D. Yanchuk. 1995.
Early selection of coastal Douglas-fir in a farm-field test environment. Silvae-Genetica 44(4): 178-186.
Keywords: genetic tree improvement
planting operations
site preparation
mechanical preparation
release treatments
chemical release
manual release
genetic relationships
wood quality
growth
Abstract:
Farm-field tests are progeny tests established using intensive site
preparation, close spacing and nearly complete weed control. Early growth and
wood density of coastal Douglas-fir (Pseudotsuga menziesii) in a farm-field environment for up to 7 years
from seed were compared with stem volume and wood density from 11 field sites
at age 13 (20-25 of commercial rotation). The farm-field test material
comprised 70 full-sib families from six 6-tree half-diallels
(some reciprocals and missing crosses) without selfs.
Parent trees were from natural stand selections in the coastal area of