USDA Forest Service RMRS-RN-31. 2006 1

United States

Department

of Agriculture

Forest Service

Rocky Mountain

Research Station

Research Note

RMRS-RN-31

September 2006

Introduction____________________

Mountain pine beetle, Dendroctonus ponderosae

Hopkins, is a primary mortality agent in ponderosa 

pine, Pinus ponderosae Dougl. Ex Laws, forests and 

has been at epidemic levels in the Black Hills of South 

Dakota since 2000. Abundant mountain pine beetlecaused tree mortality presents many forest management 

challenges to land managers. Some include, but are not 

limited to, the occurrence of mortality in high-value 

areas such as recreation areas, visual corridors, community watersheds, and vegetative sites designated as 

timber production areas. Under certain circumstances, 

mitigating the effects of mountain pine beetle-caused 

mortality is desirable, but methods to accomplish this 

are limited.

Bark beetles regulate the attack process on its host 

to avoid overcrowding the host through a very complex chemical communication system that includes the 

use of pheromones. Verbenone (4,6,6-trimethylbicyclo 

[3.1.1]-hept-3-en-2-one), has been identified as a chemical with anti-aggregation or repellent properties that 

arrests additional mountain pine beetle attacks on a tree. 

This anti-aggregation compound is insect-produced 

and is most likely released when the resource is fully 

utilized by the insects already present. The use of synthetically-produced verbenone has been experimentally 

tested for reducing the number of mountain pine beetleattacked trees in various studies, primarily in lodgepole 

pine, Pinus contorta Dougl. Ex. Loud., forests. In the 

past, results have been mixed, but some studies have 

had encouraging results.

Various studies indicate that reduced mountain 

pine beetle catches result when verbenone is added to pheromone traps that contain a mountain pine 

beetle attractant (trans-Verbenol, exo-Brevicomin, 

and myrcene) (Borden and others 1987; Schmitz and 

McGregor 1990; Amman and Lindgren 1995; Miller 

Jose Negron is a research entomologist with the USDA Forest Service, 

Rocky Mountain Research Station; Kurt Allen and Joel McMillin are 

entomologists with USDA Forest Service Forest Health in Rapid City, 

SD and Flagstaff, AZ, respectively; Henry Burkwhat is with the USDA 

Natural Resources Conservation Service, Hamilton, MT.

Testing Verbenone for Reducing Mountain Pine 

Beetle Attacks in Ponderosa Pine in the Black 

Hills, South Dakota

Jose F. Negron, Kurt Allen, Joel McMillin, 

and Henry Burkwhat

Abstract—In 2000 and 2002, Verbenone, a compound with anti-aggregation properties for 

mountain pine beetle, Dendroctonus ponderosae, was tested for reducing attacks by the insect 

in Ponderosa pine, Pinus ponderosae forests. The verbenone was released to the environment 

with the use of permeable membranes; the first year with plastic capsules (containing 0.8 g 

of verbenone) and the second year with an envelope-like pouch (containing 5.0 g of verbenone). The plastic capsules were deployed at a rate of 25 and 64 capsules per acre and a no 

capsule treatment served as control. The pouches were deployed at 30 and 50 pouches per 

acre and a no pouch treatment was the control. Mountain pine beetle attractants were placed 

on three trees at plot center to ensure insect population pressure. In neither experiment were 

there any observed differences in (1) number of mountain pine beetle-killed trees, (2) number 

of partial attacks (strip attacks), (3) number of unsuccessful attacks (pitch-outs), (4) diameter 

at breast height of infested trees, (5) attack height of infested trees, (6) mean distances of infested trees to verbenone releasers, (7) attractants located at plot center. The possible influence 

of stand environment is discussed as reason for lack of effectiveness. At this point, based on 

this and prior studies the operational use of verbenone for reducing mountain pine beetleattacked trees in ponderosa pine forests is not advisable. Further studies on this topic should be 

conducted in the future as treatment technology is developed further or the appropriate release 

amount and timing is better understood.

Key words: mountain pine beetle, verbenone, ponderosa pine, Dendroctonus ponderosae, Pinus 

ponderosae
2 USDA Forest Service RMRS-RN-31. 2006

and others 1995). Studies that also examined the use 

of verbenone to reduce mountain pine beetle attacks 

on lodgepole pine produced mixed results (Lindgren 

and others 1989; Amman and others 1989; Amman and 

others 1991; Gibson and others 1991). There are a variety of explanations associated with the mixed results 

that are discussed by Amman and Lindgren (1995) and 

Progar (2005).

Three verbenone studies in the Black Hills, South 

Dakota, Uncompahgre National Forest, Colorado (Lister 

and others 1990; Bentz and others 1989), Kootenai 

National Forest and other State and private lands south 

of Darby, Montana (Gibson and others 1991) did not 

demonstrate reduced attacks in ponderosa pine. These 

studies used bubble caps, plastic capsules that elute 

the verbenone to the environment through a permeable 

membrane.

In lodgepole pine stands in central Idaho, Progar 

(2005) examined verbenone efficacy over a 5-year 

period in the same stands. Reduced mortality was observed the first 2 years of treatment with no significant 

differences detected the following 3 years. The author 

concluded that verbenone may be effective in the early 

stages of an outbreak, but is no longer efficacious as 

insect populations increase. Bentz and others (2005) 

demonstrated efficacy of verbenone in lodgepole and 

whitebark pine sites in Idaho and Montana. These two 

studies (Progar 2005; Bentz and others 2005) used a 

pouch containing 5 g of verbenone as a release device 

instead of the bubble caps used in previous studies. The 

passive-release pouch is plastic and also elutes the verbenone through a permeable membrane but can hold 

larger amounts of the material. The amount and rapidity 

of verbenone release is based on ambient air temperatures.

In this research note we present results from a verbenone test conducted to examine potential reduction of 

mountain pine beetle attacks in ponderosa pine stands 

in 2000 and 2002 at the Black Hills, SD. In the 2000 

test, we used bubble caps and in the 2002 test, we used 

the verbenone pouch.

Methods_______________________

The 2000 test was conducted near the town of Nemo 

in the Black Hills. Thirty 1-acre plots were delineated 

for the experiment in June, 2000. Plots were at least 

2/10 of a mile apart. The diameter at breast height (dbh) 

was measured for every tree in each plot to calculate 

average tree diameter and stand stocking. Verbenone 

was deployed using passive release bubble caps (Phero 

Tech, Inc., Delta, British Columbia, Canada). Each cap 

contained 0.8 g of verbenone. The release rate provided 

by the manufacturer is 2 mg/day at 68° F and 15/per 

day at 86° F. Treatments included 25 or 60 bubble caps/

acre and an untreated control. Treatments were randomly assigned to the experimental plots. In the treated 

plots, bubble caps were evenly distributed across the 

stand and stapled on the north side of trees about 6 to 

7 ft above the ground. At the center of each plot, three 

mountain pine beetle attractants composed of transVerbenol, exo-Brevicomin, and myrcene were placed 

on host trees to assure beetle pressure in the plot. Each 

treatment was replicated 10 times. Bubble caps were 

deployed the first week in July. In the fall, after beetle 

flight was completed, every tree in each plot was examined for mountain pine beetle attack. We recorded 

whether the tree was alive (not attacked), mountain-pine 

beetle mass-attacked (successful attack), strip-attacked 

(partial beetle attack), a pitch-out (unsuccessful beetle 

attack), or mortality caused by other agents. We also 

recorded the distance from each mountain pine beetle-attacked tree to the closest verbenone bubble cap, 

distance to the plot attractant, and maximum attack 

height on each tree bole.

The 2002 test was also conducted near Nemo, SD. 

Fifteen 1-acre plots were used in this test, also at least 

2/10 of a mile apart. Verbenone was deployed using a 

the permeable plastic pouch. Each pouch contained 5 g 

of 98 percent pure verbenone. Elution rate was 25 mg/

day at 86° C. Treatments included 30 and 50 pouches/

acre and an untreated control, all of which were assigned randomly to the study plots. Five replicates of 

each treatment were conducted. Plot layout and treatment evaluation was the same as described above for 

the 2000 test. In both years, insect populations could be 

characterized as endemic. A survey of the area in 1999 

reported 2.5 infested trees/acre (McMillin and Allen 

1999)

For both years, response variables were compared using the Multi-response permutation procedure1

, which is 

based on Euclidean distance (Mielke and Barry 2001). 

When significance differences were detected, multiple 

comparisons among treatments were based on the Peritz 

1

 An Excel macro written by Rudy M. King, Station Biometrician, Rocky 

Mountain Research Station, Fort Collins, CO, was used.
USDA Forest Service RMRS-RN-31. 2006 3

closure method (Petrondas and Gabriel 1983). This test 

maintains Type I error at or below 0.05.

Results________________________

2000 Test. There were no significant differences in 

pre-treatment stocking levels among the plots that received the different treatments. Untreated control plots 

had a significantly smaller dbh compared to the plots 

treated with 25 or 64 bubble caps (P < 0.01) (table 1). 

There were no significant differences in the number of 

mountain pine beetle-killed trees, strip attacks, or pitch 

outs among treatments (table 2). Regarding mountain 

pine beetle-killed trees, there were no significant differences observed in dbh, attack height, or distance 

to attractant. Distance of attacked trees to the closest 

verbenone bubble cap was significantly higher in the 

25 caps/acre treatment compared to the 64 caps/acre 

treatment. As there were no other treatment efficacy 

differences, this distance to verbenone difference is associated with the density of caps per acre and not any 

treatment effect (table 3).

2002 Test. No significant differences were observed 

in pre-treatment stocking or dbh among study plots 

with different treatments (table 4). No significant differences were detected in the number of mass attacked 

trees among the treatments. Only one pitch-out was 

Table 1. Ponderosa pine stand characteristics prior to treatment in experimental plots, summer 2000, 

Black Hills National Forest, SD. Numbers in parenthesis denote standard error of the mean.

Mean DBH Mean Basal Area Mean Stand

Treatment (in) Mean Trees/Acre (ft2

/acre) Density Index

25 Bubble caps/Acre 9.2 (0.3) 261.9 (27.8) 116.3 (9.6) 224.3 (17.8)

64 Bubble caps/Acre 9.2 (0.3) 279.5 (18.1) 126.5 (6.0) 248.1 (10.7)

Control 8.4 (0.1) * 325.4 (23.6) 122.9 (7.2) 252.9 (17.1)

* Denotes a significant difference between both treatments and the control (P < 0.05). No other statistical differences 

observed (p < 0.05).

Table 2. Mountain pine beetle-killed Ponderosa pines, strip attacks, and pitch outs, 2000 verbenone 

test, Black Hills National Forest, SD. Numbers in parenthesis denote standard error of the 

mean.

Mean Number of Mountain Mean Number of Mean Number

Treatment Pine Beetle-Killed Trees Strip Attacks of Pitch-outs

25 Bubble caps/Acre 9.9 (2.7) 1.6 (0.5) 3.4 (0.9)

64 Bubble caps/Acre 5.8 (1.3) 1.7 (0.5) 1.5 (0.5)

Control 11.9 (3.7) 0.3 (0.2) 3.4 (0.9)

No statistical differences observed (p < 0.05).

Table 3. Mountain pine beetle-killed trees DBH, bark beetle attack height, and distances to attractant 

and closest verbenone bubble cap, 2000 verbenone test, Black Hills National Forest, SD. Numbers 

in parenthesis denote standard error of the mean.

Mean Attack Mean Distance Mean Distance 

Treatment Mean DBH (in) Height (ft) to Attractant (ft) to Verbenone (ft)

25 Bubble caps 9.7 (1.0) 10.9 (0.7) 27.4 (8.5) 18.5 (1.5) *

64 Bubble caps 10.0 (0.7) 11.4 (1.2) 13.9 (3.9) 12.4 (1.1)

Control 8.7 (0.9) 11.3 (1.1) 20.6 (4.8) NA

* Denotes a significant difference between both treatments (P < 0.01). No other statistical differences observed 

(p < 0.05).
4 USDA Forest Service RMRS-RN-31. 2006

recorded in the 30 pouches/acre treatment; no differences occurred between the control and the 50 pouches/acre 

treatment (table 5). No strip attacks were observed in any 

of the plots. There were few plots with attacked trees in 

this test. In two of the control plots, three plots of the 30 

pouches/acre treatment and one plot with 50 pouches/

acre, no attacked trees were recorded. Therefore, comparing attacked tree characteristics among plots is not 

meaningful. For descriptive purposes, we present mean 

dbh, attack height, and distance to attractant and nearest verbenone pouch for all attacked trees in every plot 

(table 6). No trends of particular interest are noted.

Discussion_____________________

Mountain Pine Beetle-Caused Mortality 

Levels

In the 2000 test, a total of 119, 99, and 58 mountain 

pine beetle-killed trees were counted in the control, 25, 

and 64 bubble cap treatments, respectively. These numbers represent 3.7, 3.8, and 2.1 percent of the total trees 

in the control, 25, and 64 bubble cap plots, respectively. 

In the 2002 test there were 26, 6, and 27 mountain pine 

beetle-killed trees in the control, 30 pouches/acre, and 

50 pouches/acre, respectively. These numbers represent 

0.8, 0.3, and 1.3 percent of the total trees in the control, 

30 pouches/acre, and 50 pouches/acre, respectively.

In their studies at the Black Hills and the Uncompahgre 

NF, Bentz and others (1989) examined the use of bubble 

caps in ponderosa pine using 10, 20, 40, or 80 caps/acre 

and a control and observed no differences among treatments. The percent of trees attacked in their study plots 

ranged from 1 to 7 percent in the Black Hills and from 

15 to 41 percent in the Uncompahgre NF. The most 

promising results were presented by Lister and others 

(1990) in another experiment in the Black Hills, using the same rates of bubble caps as Bentz and others 

(1989). They did not observed significant differences 

among treatments yet reported a consistent decrease in 

the number of attacked trees per plot from 29.1 in the 

Table 6. Mountain pine beetle-killed trees DBH, bark beetle attack height, and distances to attractant and 

closest verbenone bubble cap, 2002 verbenone test, Black Hills National Forest, SD. Numbers in parenthesis 

denote standard error of the mean.

Mean Attack Mean Distance to Mean Distance to

Treatment Mean DBH (in) Height (ft) Attractant (ft) Verbenone (ft)

30 Pouches per Acre 9.7 (0.7) 16 (2.7) 2.2 (1.3) 12.2 (3.2)

50 Pouches per Acre 8.6 (0.4) 12.7 (1.0) 25.9 (7.7) 10.7 (1.2)

Control 9.1 (0.5) 14.5 (1.6) 25.4 (7.2) NA

No statistical comparisons made. See text for more details.

Table 4. Ponderosa pine stand characteristics prior to treatment in experimental plots, summer 2002, 

Black Hills National Forest, SD. Numbers in parenthesis denote standard error of the mean.

Mean Trees Mean Basal Area Mean Stand

Treatment Mean DBH (in) per Acre (ft2

/acre) Density Index

30 Pouches/Acre 7.5 (0.4) 379.0 (17.8) 158.4 (27.3) 258.4 (12.6)

50 Pouches/Acre 8.1 (0.6) 409.6 (72.4) 152.0 (13.3) 289.4 (30.7)

Control 7.0 (0.8) 603.2 (214) 175.4 (33.9) 317.2 (46.3)

No statistical differences observed (p < 0.05).

Table 5. Mountain pine beetle-killed Ponderosa pines and pitch outs, 2002 verbenone test, Black Hills National Forest, SD. 

Numbers in parenthesis denote standard error of the mean.

Treatment Number of Trees Number of Mass-attacked Trees Number of Pitch-outs

30 Pouches/Acre 6 1.2 (1.0) Only 1 tree in one plot

50 Pouches/Acre 27 5.4 (1.6) 1.0 (0.4)

Control 26 5.2 (3.4) 2.8 (1.5)

No statistical differences observed (p < 0.05).
USDA Forest Service RMRS-RN-31. 2006 5

control to 5.6 in a 68 bubble caps per acre treatment. 

The authors did not report the percent of trees attacked 

by mountain pine beetle in the study. Gibson and others 

(1991) conducted another study in ponderosa pine in 

the Kootenai NF. They used the same bubble caps rates 

as above. They observed no differences among treatments. That study reported percent of attacked trees 

varied from 2.3 to 15.8 percent.

In lodgepole pine, Progar (2005), using the verbenone pouch releaser (eluting 25 mg/day at 86 °F) at a 

rate of 20 per 1⁄4 acre, reported successful reduction in 

mountain pine beetle-caused mortality during the first 

2 years of treatment, but no reduction was found in the 

following 3 years. In this study, median percent mortality levels after 2 years were 12 and 59 percent of the 

trees > 5.1 inches in the treated and untreated stands, 

respectively. After 5 years, the percentages were 67 

and 87 in the treated and untreated stands, respectively. 

Bentz (2005) reported increased effectiveness using 40 

pouches/acre (with a higher elution rate of 50 mg/day at 

86 °F) compared to the control. In this study, the number of trees/plot ranged from 10 to 335 trees. Attacked 

tree percentages ranged from 0.1 to 20 percent in the 

control plots and from 4 to 60 percent in the verbenonetreated plots.

Although it is difficult to adequately compare differences in bark beetle population pressure, stand/site 

conditions, and treatments from the various studies, 

they do cover a wide range of attacked trees from as 

low as 1 percent to as high as 41 percent. This suggests 

that insect population densities, although certainly low 

in our study, may not be the single attribute affecting 

our results where no differences between treatments 

were observed.

Verbenone and Stand Microclimate

Amman and Lindgren (1995) discuss several potential reasons for inconsistencies in results of previous 

studies. They mention that weather factors, such as 

high temperatures, may cause verbenone to elute prior 

to beetle dispersal. Holsten and others (2002) measured 

release rates, under field conditions, from bubble caps 

filled with either verbenone or methylcyclohexenone 

(antiaggregant for Douglas-fir beetle, Dendroctonus 

pseudotsugae). They concluded that ambient air and 

litter layer temperatures were key determinants influencing release rates with higher temperatures resulting 

in faster release rates. Amman and Lindgren (1995) 

also indicate that when verbenone is exposed to light, 

isomarization takes place, which changes verbenone to 

chrysanthenone, a chemical that does not affect mountain pine beetle behavior.

Various studies using pheromone surrogates have 

demonstrated that turbulence and the meteorology 

within the forest canopy can influence pheromone dispersion (Aylor and others 1976; Murlis and Jones 1981; 

Elkinton and others 1984; Mafra-Neto and Carde 1994). 

Recently, Thistle and others (2005) started an examination in Mississippi of the influence of stand thinning 

on the dispersion of a chemical that acted as a pheromone surrogate. Preliminary results suggest that solar 

radiation increases in a loblolly pine, Pinus elliotii 

Engelm., stand thinned to 70 ft2/acre basal area. This 

results in unstable air creating a turbulent environment 

compared to an unthinned stand. This may increase 

pheromone dispersion affecting pheromone cues used 

by insects to communicate.

Bartos and Amman (1989) examined stand microclimate in a thinned and an unthinned lodgepole pine stand. 

The unthinned stand had a basal area of 161 ft2

/acre, 

441 trees/acre and a mean dbh of 7.3 in. The thinned 

stand had a basal area of 96 ft2/acre, 287 trees/acre, 

and a mean dbh of 8.0 inches. All measurements were 

significantly different between the thinned and the unthinned stands. They observed increased light intensity, 

wind movement, and temperature in the thinned stand 

compared to the unthinned stand. In the Black Hills, 

Schmid and others (1992) indicated no significant differences in vertical wind speeds between a ponderosa 

pine stand thinned to 60 GSL, two stands cut to 80 GSL, 

and a unthinned stand of 150 GSL (GSL = Basal area 

when average stand diameter is 10 inches).

In another study, Schmid and others (1995) compared 

microclimate characteristics between a thinned and an 

unthinned ponderosa pine stand in the Black Hills. The 

unthinned stand had a basal area of 148 ft2/acre and a 

mean dbh of 10.8 in, whereas the thinned stand had a 

basal area of 79.2 ft2/acre and a mean dbh of 11.2 in. 

They observed no significant differences in air temperature or horizontal air speed, but reported increased solar 

radiation in the thinned stand. Comparing the lodgepole pine study with the ponderosa pine study is not 

feasible because overall environmental conditions and 

stand structures are most likely different. However, it 

is evident that a more open lodgepole pine stand had 

different environmental conditions than a dense, unthinned stand. Thistle and others (2005) suggest that 

pheromones may be more widely dispersed in open 

stands, making it less effective. Lodgepole pine forest 

canopy cover is denser than canopy structures found in 

ponderosa pine forests. Schmid and others (1995) only 

observed differences in solar radiation, yet it was not a 

replicated study and may have been conducted under 

abnormal weather conditions.
6 USDA Forest Service RMRS-RN-31. 2006

Conclusions____________________

Because ponderosa pine stand structures are less 

dense, they probably experience higher temperatures, 

high solar radiation, and increased wind movement. 

These microclimate patterns may result in a more 

turbulent environment that disperses the pheromone 

affecting insect communication. This may explain the 

consistent observations where verbenone treatments 

applied in ponderosa pine stands are not efficacious. 

Further testing of verbenone applications in ponderosa 

pine stands should be conducted. These studies should 

include higher release rates and the use of timed release 

devices that target daily and seasonal bark beetle peak 

flight to enhance pheromone exposure to the insects and 

minimize loss to dispersion.

Management Implications_________

Studies to date on the use of verbenone to reduce 

mountain pine beetle-killed trees in ponderosa pine 

stands have not detected significant reductions in the 

number of trees attacked. Operational use of this strategy in ponderosa pine forests is not advisable at this 

point until further studies prove otherwise.

Literature Cited_________________

Amman, G.D.; Lindgren, B.S. 1995. Semiochemicals for management of mountain pine beetle: status of research and application, 

pp. 14-22. In: Salom, S.M.; Hobson, K.R., eds. Application of 

semiochemicals for management of bark beetle infestationsProceedings of an informal conference, GTR-INT-318, USDA 

Forest Service, Intermountain Research Station, Ogden, UT.

Amman, G.D.; Their, R.W.; McGregor, M.D.; Schmitz, R.F. 1989. 

Efficacy of verbenone in reducing lodgepole pine infestation 

by mountain pine beetle in Idaho. Canadian Journal of Forest 

Research 19: 64-60.

Amman, G.D.; Their, R.W.; Weatherby, J.C.; Rasmussen, L.A.; 

Munson, S.A. 1991. Optimum dosage of verbenone to reduce 

infestation of mountain pine beetle in lodgepole pine stands of 

central Idaho. Research Paper INT-440, USDA Forest Service, 

Intermountain Research Station, Ogden, UT. 5 p.

Aylor, D.; Parlange, J.; Granett, J. 1976. Turbulent dispersion 

of disparlure in the forest and male gypsy moth response. 

Environmental Entomology 5: 1026-1032.

Bartos, D.L.; Amman, G.D. 1989. Microclimate: an alternative 

to tree vigor as a basis for mountain poine beetle infestations. 

Research Paper INT-400, USDA Forest Service, Intermountain 

Research Station, Ogden, UT. 10 p.

Bentz, B.; Lister, C.K.; Schmid, J.M.; Mata, S.A.; Rasmussen, 

L.A.; Haneman, D. 1989. Does verbenone reduce mountain pine 

beetle attacks in susceptible stands of ponderosa pine? Research 

Note RM-45, USDA Forest Service, Rocky Mountain Forest and 

Range Experiment Station, Fort Collins, CO. 4 p.

Bentz, B.J.; Kegley, S.; Gibson, K.; Their, R. 2005. A test of high-dose 

verbenone for stand-level protection of lodgepole and whitebark 

pine from mountain pine beetle (Coleoptera: Curculionidae: 

Scolytinae) attacks. Journal of Economic Entomology 98: 

1614-1621.

Borden, J.H.; Ryker, L.C.; Chong, L.J.; Pierce, H.D. Jr.; Johnston, 

B.D.; Oehlschlager, A.C. 1987. Response of the mountain 

pine beetle (Dendroctonus ponderosae Hopkins, Coleoptera: 

Scolytidae), to five semiochemicals in British Columbia lodgepole pine forests. Canadian Journal of Forest Research 17: 

118-128.

Elkinton, J.; Carde, R.; Mason, C. 1984. Evaluation of time-average 

dispersion models for estimating pheromone concentration in a 

deciduous forest. Journal of Chemical Ecology 10: 1081-1108.

Gibson, K.E.; Schmitz, R.F.; Amman, G.D.; Oakes, R.D. 1991. 

Mountain pine beetles response to different verbenone dosages 

in pine stands of western Montana. Research Paper INT-444, 

USDA Forest Service, Intermountain Research Station, Ogden, 

UT. 11 p.

Holsten, E.H.; Webb, W.; Shea, P.J.; Werner, R.A. 2002. Release 

rates of methylcyclohexenone and verbenone from bubble caps 

and bead releasers under field conditions suitable for the management of bark beetles in California, Oregon, and Alaska. Research 

Paper PNW-RP-544, USDA Forest Service, Pacific Northwest 

Research Station 21 p.

Lindgren, B.S.; Borden, J.H.; Cushon, G.H.; Chong, L.J.; Higgins, 

C.J. 1989. Reductions of mountain pine beetle (Coleoptera: 

Scolytidae) attacks by verbenone in lodgepole pine stands in 

British Columbia. Canadian Journal of Forest Research 19: 65-

68.

Lister, C.K.; Schmid, J.M.; Mata, S.A.; Haneman, D.; O’Neil, C.; 

Passek, J.; Sower, L. 1990. Verbenone bubble caps ineffective 

as a preventive strategy against mountain pine beetle attacks in 

ponderosa pine. Research Note RM-501, USDA Forest Service, 

Rocky Mountain Forest and Range Experiment Station, Fort 

Collins, CO. 3 p.

Mafra-Neto, A.; Carde, R.T. 1994. Fine-scale structure of pheromone plume modulates upwind orientation of flying moths. 

Nature 369: 142-144.

McMillin, J.J.; Allen, K.E. 1999. Evaluation of mountain pine beetle 

activity in the Black Hills National Forest. Forest Health, USDA 

Forest Service, Renewable Resources, Rocky Mountain Region. 

Biological Evaluation R2-00-03. 18 p.

Miller, D.R.; Borden, J.H.; Lindgren, B.S. 1995. Verbenone: dosedependent interruption of pheromone based attraction of three 

sympatric species of pine bark beetles (Coleoptera: Scolytidae). 

Environmental Entomology 24: 692-696.

Mielke, P.W., Jr.; Kenneth, B.J. 2001. Permutation methods: A distance function approach. Springer-Verlag, New York. 352 p.

Murlis, J.; Jones, C. 1981. Fine scale structure of odour plumes in 

relation to insect orientation to distance pheromone and other attractant sources. Physiological Entomology 6: 71-86.

Petrondas, D.A.; Gabriel, K.R. 1983. Multiple comparisons by rerandomization tests. Journal of the American Statistical Association 

78: 949-957.

Progar, R.A. 2005. Five-year operational trial of verbenone to 

deter mountain pine beetle (Dendroctonus ponderosae; 

Coleoptera: Scolytidae) attack of lodgepole pine (Pinus contorta). Environmental Entomology 34: 1402-1407.
USDA Forest Service RMRS-RN-31. 2006 7

Schmid, J.M.; Mata, S.A.; Allen, D.C. 1992. Potential influences of 

horizontal and vertical air movement in ponderosa pine stands 

on mountain pine beetle dispersal. Research Note RM-516. Fort 

Collins, CO: USDA Forest Service, Rocky Mountain Forest and 

Range Experiment Station. 4 p.

Schmid, J.M.; Mata, S.A.; Olsen, W.K. 1995. Microclimate and 

mountain pine beetles in two ponderosa pine stands in the Black 

Hills. Research Note RM-532, USDA Forest Service, Rocky 

Mountain Forest and Range Experiment Station, Fort Collins, 

CO. 12 p.

Schmitz, R.F.; McGregor, M.D. 1990. Antiaggregative effect of verbenone on response of the mountain pine beetle to baited traps. 

You may order additional copies of this publication by sending your mailing 

information in label form through one of the following media. Please specify the 

publication title and series number.

Fort Collins Service Center

Telephone (970) 498-1392

FAX (970) 498-1122

E-mail rschneider@fs.fed.us

Web site http://www.fs.fed.us/rm

Mailing address Publications Distribution

Rocky Mountain Research Station

240 West Prospect Road

Fort Collins, CO 80526

Rocky Mountain Research Station

Natural Resources Research Center

2150 Centre Avenue, Building A

Fort Collins, CO 80526

Research Paper INT-423, USDA Forest Service, Intermountain 

Research Station, Ogden, UT. 7 p.

Thistle, H.W.; Peterson, H.; Alwine, G.; Lamb, B.; Edburg, S.; 

Strom, B. 2005. The influence of stand thinning on surrogate 

pheromone plumes. In: Proceedings 16th U.S. Department of 

Agriculture Interagency Research Forum on Gypsy Moth and 

Other Invasive Species, 2005. 18-21 January, Annapolis, MD. 

General Technical Report NE-337, USDA Forest Service, 

Northeastern Research Station, Newtown Square, PA.
The Rocky Mountain Research Station develops scientific 

information and technology to improve management, 

protection, and use of the forests and rangelands. Research is 

designed to meet the needs of the National Forest managers, 

Federal and State agencies, public and private organizations, 

academic institutions, industry, and individuals.

Studies accelerate solutions to problems involving 

ecosystems, range, forests, water, recreation, fire, resource 

inventory, land reclamation, community sustainability, forest 

engineering technology, multiple use economics, wildlife 

and fish habitat, and forest insects and diseases. Studies 

are conducted cooperatively, and applications may be found 

worldwide.

Research Locations

Flagstaff, Arizona Reno, Nevada

Fort Collins, Colorado* Albuquerque, New Mexico

Boise, Idaho Rapid City, South Dakota

Moscow, Idaho Logan, Utah

Bozeman, Montana Ogden, Utah

Missoula, Montana Provo, Utah

*Station Headquarters, Natural Resources Research Center, 2150 

Centre Avenue, Building A, Fort Collins, CO 80526.

The U.S. Department of Agriculture (USDA) prohibits discrimination 

in all its programs and activities on the basis of race, color, national 

origin, age, disability, and where applicable, sex, marital status, familial 

status, parental status, religion, sexual orientation, genetic information, 

political beliefs, reprisal, or because all or part of an individual’s income 

is derived from any public assistance program. (Not all prohibited 

bases apply to all programs.) Persons with disabilities who require 

alternative means for communication of program information (Braille, 

large print, audiotape, etc.) should contact USDA’s TARGET Center at 

(202) 720-2600 (voice and TDD). To file a complaint of discrimination, 

write to USDA, Director, Office of Civil Rights, 1400 Independence 

Avenue, S.W., Washington, DC 20250-9410, or call (800) 795-3272 

(voice) or (202) 720-6382 (TDD). USDA is an equal opportunity 

provider and employer.

RMRS

ROCKY MOUNTAIN RESEARCH STATION

Federal Recycling Program Printed on Recycled Paper