Chemical control of clubmoss (Selaginella densa Rydb.)
by Don Wilms Stroud
A thesis submitted to the Graduate Faculty in partial fulfillment of the requirements for the degree of
MASTER OF SCIENCE IN Range Management
Montana State University
© Copyright by Don Wilms Stroud (1970)
Abstract:
Selective chemical control of Selaginella densa Rydb. was investigated at three locations involving 15
trials representing spring, summer and fall treatments from "1964 through 1968. Treatments were
evaluated for percent clubmoss control, vegetational change, and production of herbage.
Results of the trials indicated that 10 lbs/A of AMS or 2 lbs/A of atrazine or monuron would control
clubmoss and increase herbage production.
Atrazine and monuron killed existing fringed sagewort plants and prevented refinfestation for one or
more growing seasons.
The addition of 50 lbs/A of nitrogen to atrazine and monuron treatments significantly increased the
production of herbage over herbicidal treatments alone. In presenting this thesis in partial fulfillment of the require­
ments for an advanced degree at Montana State University, I agree that
the Library shall make it freely available for inspection.
I further
agree that permission for extensive copying of this thesis for scholarly
purposes may be granted by my major professor, or, in his absence, by
the Director of Libraries.
It is understood that any copying or publi­
cation of thjLs thesis for financial gain shall not be allowed without
my written permission.
CHEMICAL CONTROL-OF CLUBMOSS,
(Selaginella densa Rydb.)
V
■
Don Wilms S troud
A thesis submitted to the Graduate Faculty in partial
fulfillment of the requirements for the degree
'of
.MASTERfOF SCIENCE
-■
»
;
Range Management
Approved:
T T MMa./sfcxsi* i P
Head, Major Department
'
Chairman, Examining Committee"
MONTANA STATE UNIVERSITY;
Bozeman, Montana
December, 1970
iii
ACKNOWLEDGEMENT
The author would like to express his sincere appreciation to
Laurence 0„ Baker for his valuable advice, constructive criticism and
encouragement throughout the course of this investigation.
Appreciation is also expressed to Dr. Erwin Smith for his advice
and assistance in processing the data at the Montana State University
Computer Center, and to Dr. G. F. Payne and Dr. Don E. Ryerson for their
assistance throughout the bourse of the study.
Special thanks is extended to the Bureau of Land Management who
supplied the grant under which this project was carried out.
iv
TABLE OF CONTENTS
VITA..... ............ ........... ...................................
ACKNOWLEDGEMENTS...............
ii
iii
TABLE OF CONTENTS........................ ......... ...... *..........
iv
LIST OF TABLES....... ............ ..................................
v
LIST OF APPENDIX TABLES...................... ........ ..............
viii
LIST OF FIGURES.............................
ix
x
INTRODUCTION...... ........................
I
REVIEW OF LITERATURE........ ............... ........... .............
3
MATERIALS AND METHODS........ ............................... .
8
VO OO CO
ABSTRACT............ ............... ......... ........................
STUDY AREAS.....
Havre Site..
Glasgow Site
Norris Site..................... .................. ....... .
10
CHEMICAL CONTROL.......................... .......... ............
11
NITROGEN-WATER.......
14
RESULTS AND DISCUSSION....... ............ ......... ................
15
CLUBMOSS CONTROL,....... ........ .'............... .......... .
Herbage Yields............... .................. ............
Species Response to Herbicides............................
Herbicide Effects on Fringed Sagewort.... .............
Chemical-Nitrogen I n t e r a c t i o n ; .......
Nitrogen-Water............
15
20
34
39
39
45
SUMMARY...........
52
APPENDIX...........
53
LITERATURE CITED...............................
58
V
LIST OF TABLES
1.
2.
Physical and chemical characteristics of AMS, atrazine
and monuron.................................... ...... ...........
5
Percent clubmoss control in June, 1967 from herbicidal
applications at Glasgow, Havre and Norris for treatments
made during 1964, 1965 and the spring of 1966..................
16
3.. Percent clubmoss control from treatments made at Norris
with and without surfactants.......... .................... .
4.
5.
6.
7.
18
Pounds of dry matter produced by the untreated check
from each test during each year at each location...............
21
Herbage yields in 1964, 1965, 1966 and 1967 as a percent
of average check following herbicidal applications in
the spring of 1964 at Havre and Norris for selective
control of clubmoss..... ................................. .
23
Herbage
average
fall of
control
24
yields in 1965, 1966 and 1967 as a percent of
check following herbicidal applications in the
1964 at Glasgow, Havre and Norris for selective
of clubmoss.......... ...... ........ .......... ...... .
Herbage yields in 1965, 1966 and 1967 as a percent of
average check following herbicidal applications in the
spring of 1965 at Glasgow, Havre and Norris for
selective control of clubmoss......... ......... ...............
25
Herbage yields in 1966 and
check following herbicidal
1965 at Glasgow, Havre and
of clubmoss................
1967 as a percent of average
applications in the fall of
Norris for selective control
................ ......... ...........
26
Herbage yields in 1966 and 1967 as a percent of average
check following herbicidal applications in the spring
of 1966 at Havre and Norris for selective control of
clubmoss,................ ............................ ...........
27
10. Herbage yields in 1965, 1966 and 1967 following herbi­
cidal treatments at Glasgow in the fall of 1964 and
spring of 1965 for selective control of clubmoss..............
28
8.
9.
vi
LIST OF TABLES (Continued)
11. Herbage yields in 1965, 1966 and 1967 following
herbicidal treatments at Havre in the fall of 1964
and spring of 1965 for selective control of clubmoss..........
29
12. Herbage yields in 1965, 1966 and 1967 following
herbicidal treatments at Norris in the fall of 1964
and spring of 1965 for selective control of clubmoss........ .
30
13. Herbage yields expressed as percent of check the first,
second, third and fourth growing seasons after treat­
ment with AMS 10, atrazine 2, monuron 2, and paraquat
.5 Ibs/A applied for selective control of clubmoss............
32
14. Yields of blue grama, needleandthread, prairie junegrass and forbs in 1965, 1966 and 1967 following
herbicidal application at Havre in the fall of 1964,
for selective control of clubmoss.................
35
15. Yields of blue grama, needleandthread, prairie junegrass and forbs in 1965, 1966 and 1967 following
herbicidal application at Havre in the spring of 1965,
for selective control of clubmoss........... .......... .
36
16. Yields of blue grama, needleandthread, misc. grasses
(annual and perennial) and forbs in 1965, 1966 and
1967 following herbicide application at Norris in
the fall of 1964, for selective control of clubmoss..... ......
37
17. Yields of blue grama, needleandthread, misc. grasses
(annual and perennial) and forbs in 1964, 1965 and
1967 following herbicidal application at Norris in
the spring of 1965, for selective control of clubmoss.........
38
18. Yield of fringed sagewort in 1967 at Glasgow follow­
ing applications of herbicides at various times
for control of clubmoss.......... .......... .................. .
40
19. Yields as a percent of check in 1966 and 1967
following application of herbicides and nitrogen
at Glasgow, Havre and Norris in the fall of 1965
and Havre and Norris in the spring of 1966.................... .
42
vii
LIST OF TABLES (Continued)
20. Effects of several herbicides and 50 Ibs/A nitrogen
on herbage yields following applications at Havre
and Norris in the fall of 1965............... .
43
21. Effects of nitrogen on several species of herbage
with all herbicides combined for treatments made
in the fall of 1965 at Havre and Norris............ ...........
44
22. Response of herbage to four levels of nitrogen and
water on clubmoss infested range for each of two
years at Norris..................................... ....... ..
46
23. Response of herbage to four levels of nitrogen
following application in May, 1965 at Norris................ .
24. Effect of four levels of water applied during the
growing season in 1965 and 1966 on herbage yield.
...... .
. 47
47
25. Herbage yields in 1965 and 1966 expressed as percent
of check following applications of nitrogen and
water at Norris...... ....... ............. ...... ........ .
48
26. Forage yield in 1965 and 1966 from the nitrogen-water
treatments at Norris for needleandthread and miscel­
laneous forbs and shrubs.................... ................ ..
51
viii
LIST OF APPENDIX TABLES
I*
P l 3Tlt T13H1G
5A
2«
OtiGim c a l xiaiiiGs#*o**#»@*#*m*#*#9**$**$<,**********@**$**#f*###*t*
55
3.
Percent clubmoss control in June, 1967 on treatments
made in the spring of 1964 at Havre and N
o
r
r
4.
i
s
56
Precipitation measurements from the nearest weather
station for each experimental site.... .............. . *...... .
57
ix
LIST OF FIGURES
1.
2.
Herbage yields expressed as percent of check the 1st,
2nd, 3rd and 4th growing seasons after treatments
with AMS 10, atrazine 2 and monuron 2 Ibs/A applied
for selective control of clubmoss..... ....... ............... ..
33
Herbage yields in 1965 and 1966 expressed as percent
of check following the application of nitrogen and
water at Norris
49
X
ABSTRACT
Selective chemical control of Selaginella densa Rydb. was investi­
gated at three locations involving 15 trials representing spring, summer
and fall treatments from 1964 through 1968. Treatments were evaluated
for percent clubmoss control, vegetational change, and production of
herbage.
Results of the trials indicated that 10 Ibs/A of AMS or 2 Ibs/A of
atrazine or monuron would control clubmoss and increase herbage produc­
tion.
Atrazine and monuron killed existing fringed sagewort plants and
prevented refinfestation for one or more growing seasons.
The addition of 50 Ibs/A of nitrogen to atrazine and monuron treat­
ments significantly increased the production of herbage over herbicidal
treatments alone.
INTRODUCTION
Selaginella densa Rydb., commonly called dense clubmoss (hereafter
referred to as clubmoss) is a spore producing, mat-forming plant common
to extensive areas of the Northern Great Plains and foothill-mountain
regions bordering the plains.
Clubmoss is found on native rangeland throughout the State of Mon­
tana, except at extremely high elevations and some sedimentary plains
areas in the southeastern part of Montana.
Clubmoss is most abundant on
plains and foothill ranges east of the Continental Divide and north of
the Missouri.River,
Apparently clubmoss prefers well developed soils of
medium texture and nearly neutral reaction on level to moderately sloping
topography (Payne e t a l . , 1967).
Substantial acreages of land administrated by the Bureau of Land
Management in northern Montana are infested with clubmoss.
To aid in
future management of clubmoss infested range the Bureau entered into a
research contract with the Montana Agricultural Experiment Station in
1963 to study clubmoss.
Mechanical methods of clubmoss control were investigated by the
Animal & Range Sciences Department and reported by Dolan (1966) and
Ryerson et al. (1969).
Soil-water relationships were studied by Hotilton
at the North Montana Branch Station and reported by Ryerson jet al. (1969).
Chemical methods of clubmoss control were studied by the Plant and
Soil Science Department.
(1966).
Preliminary results were reported by Wagner
This thesis represents a continuation of the work he initiated
“2?"
and summarizes results of all selective chemical control work on clubmoss .
REVIEW OF LITERATURE
Dolan (1966) and Wagner (1966) extensively reviewed the literature
available on clubmoss.
Their reviews covered taxonomy, reproduction,
growth, cytology and factors affecting distribution and control of clubmoss,
No additional literature was available since completion of their
reviews except for
that originating in Montana.
Although low in stature clubmoss was found to be an important com­
ponent of the vegetation present because of its high degree of ground
cover (over 90 percent basal cover in some heavy infestations) (Ryerson
jBt aJL., 1969).
Clubmoss was found throughout Montana except at extremely
high elevations and some sedimentary plains areas (Payne et aJ., 1967).
On clubmoss infested range Houlton seldom found available moisture
below 18 inches at the beginning of the growing season.
rapidly depleted as the growing season progressed.
Reserve moisture
He attributed these
losses to suspected high evapotranspirational rates of clubmoss.
He
found that evapotranspiration losses continued to occur in the late
summer whenever light rains fell, even though grasses were in a summer
dormant condition (Ryerson et al., 1969),
Yearly herbage production from pitting and scalping at the North
Montana Branch Station (Havre) consistently exceeded check yields.
Scalping-with-seeding outyielded pitting at the Nyquist allotment near
Glasgow and in some tests at Havre (Ryerson et al.* 1969).
Wagner (1966) in reporting 1964 results of herbicides applications
made in the field during the spring of 1964 found that clubmoss was
controlled by several chemical treatments.
Herbage yields increased
following certain treatments (AMS9 atrazine) but were reduced by monuron
and paraquat!/.
Bromacil treatments destroyed all vegetation present.
Reduction of live and dead clubmoss ground cover 30 years after
mechanical treatments was observed by Dolan (1966).
Three annual applications of 100 pounds of nitrogen per acre signify
icantly reduced dormant clubmoss ground cover but did not affect live
clubmoss.
Water9 however9 increased both live and dormant clubmoss
ground cover.(Klages and Ryerson9 1965).
Herbage yield increases with applications of 40=320 Ibs/A of nitro­
gen plus monuron at I Ib/A were greater than with nitrogen alone
(Choriki e_t al.^ 1969).
A standardized system of reporting herbicide characteristics was
developed by the Weed Society of America (1967),
Information regarding
physiological and biochemical behavior, behavior in or on soils9 toxi­
cological properties, physical properties and use were some of the items
requested for each herbicide from the manufacturer.
Information regard­
ing three of the chemicals tested is summarized in Table I.
AMS is rapidly absorbed by foliage, is highly soluble and is subject
to leaching in the soil.
However9 AMS is also rapidly decomposed by
microbial action in the soil.
Atrazine and monuron are less subject to leaching, being more
readily adsorbed by clay particles and organic matter.
I/ Full chemical names are given in Appendix Table 2.
They are also
Table I,
Physical and chemical characteristics of AMSs atrazine and monuronJ:/.
Physiological and
Biochemical Behavior
"Solubility in water
at"25° C
Absorption
Translocation
AMS
68.4 ppmw
Rapidly absorbed
through foliage and
stems.
Translocation does
occur.
Mechanism of action
Atrazine
Monuron
70 ppmw
Through both roots
and foliage, Foliage
absorption often
small.
Translocated aero=
petalIy in the xylem
and accummulates in
the apical meristerns.
A photosynthetic
inhibitor.
230 ppmw
Readily absorbed
through root system,
less so in foliage
and stems.
Primarily upward in
the xylem.
More readily adsorbed
on muck or clay soils
than on soils of low
clay and organic mat­
ter. Not normally
found below upper
foot of soil.
Probably accounts for
major breakdown in the
soil. Micro-organisms
can utilize it as a
source of energy and
N.
Increases as clay
and/or organic matter
increases, leaching
not important. '
Strong inhibitor of
the Hill reaction.
Behavior in or on soils
Adsorption and
leaching
Not retained in Soilss
moves like chlorate.
Microbial, breakdown
Species of fungi and
bacteria converted
sulfamate to sulfate
in approx, equimolar
proportions to amount
of N assimilated.
I/
Information obtained from the Herbicide Handbook 1967
Primary factor in dis­
appearance from soils
Some organisms can
use monuron as sole
source of carbon.
Table I (continued)»
Behavior in or on
Soils
AMS
Both occur to some
extent. More subject
to UV and volatility.
Loss from photo=
decomposition and/or
volitalization.
Average persistence
at recommended rate
Atrazine
6=8 weeks at 3 lbs.
per 1000 sqi ft. under
humid eastern con=
ditions.
Most rotational crops
can be planted I year
after application,
except under arid or
semi=arid climate.
Monuron
Probably are insig­
nificant except when
exposed on soil sur­
face for extended
length of time.
At lower ^.-selective rates
phytotoxic concen­
trations disappear
within one season.
Higher rates may re- o
quire more than one
T
season. Accumulation
from annual applica­
tion is not a problem.
Toxicological properties
General toxicity
td'wildlife.
Deer fed A M S "treated
foliage suffered no
ill effects.
Information pro=
vided by
E .I.DuPont"deNemours
and Company.
Investigations con=
ducted on 2 species
of birds arid 3
species of fish,
showed a very low
toxicity..
Geigy Agricultural
Chemicals.
E „I „ DuPont deNemours
and Company
-7-
subject to microbial breakdowns but. at a slower rate than AMS.
would be expected to appear in ground water.
Neither
Movement in surface water
would be dependent on movement of soil particles to which the chemical
was adsorbed (WSA 1967).
MATERIALS-ANB METHODS
STUDY AREAS.°
Herbicides.which appeared to control elubmoss in initial greenhouse
experiments by Wagner (1966) were further evaluated in field trials.
These trials were conducted at the North Montana Branch Station near
Havre (Havre site), the Buggy Creek State Grazing District (Fabian
Nyquist allotment) near Glasgow (Glasgow site) and the Red Bluff Research
Ranch hear Norris'. (Norris site).
Havre Site.”
This heavily infested c lubmoss site is located on a
gently undulating glacial till plain dissected by moderately deep coulees.
The approximate elevation is 2,800 feet.
Average annual precipitation
is 11.25 inches measured at Fort Assinniboine five miles north of the
site.
The dominant soils are Telstad loams with other unidentified soils
occurring locally in small vegetated micropits.
Telstad soils are
classified in the fine-loamy, mixed family of Aridic Argiborols.
larity with the Scobey classification is noted.
Simi­
Typically Telstad soils
have grayish brown loam surface, brown prismatic clay loam B2, ca, and C
horizons.
The thickness of solum over the calcareous ca horizons ranges
from 10 to 15 inches.
the profile.
JL/
Compared with Seobey there is less clay throughout
Both soils are. well drained and moderately permeable!/.
Classification of soils at all study sites have been made by Soil
Conservation Service Soil Scientists Fred A. Boettcher, R. L 0 Moshier,
R. E. Richardson and J. L. Parker.
Information much the same as re­
ported by Ryerson et al,, 1969.
9-
Natiwe vegetation other than clubmoss is dominated by needleandthread and blue grama.
Associated grasses and grass=like plants include
Sandberg bluegrass* prairie junegrass, plains reedgrass, western wheat*=*
grass9 green needlegrass, six-weeks fescue and needleleaf sedgel/.
Important forbs are scarlet globemallow, Hoods phlox, American
vetch, hairy goldenaster, penstemon, pussytoes, milkvetches, cudweed
sagewort and green sagewort.
Half-shrubs include fringed sagewort and
broom snakeweed.
Glasgow Site.-
This area is located approximately 3 miles north and
one and one-half miles west of the Glasgow Air Force Base.
Soils of the Glasgow study area were formed on a gently rolling till
plain at an elevation of 2,300 feet.
Average annual precipitation is
12.27 inches measured at Glasgow airport 25 miles south of site.
On the
more level slopes and in the swales and drainage areas, the soils are
Thoeny loams classified in the fine montmorillonitic family of Borollie
Natragids,
Typically they have grayish brown loam A2, columnar clay B2t,
clay loam B3ca, Cca and C horizons.
a depth of about 10 inches.
The platy structured A2 extends to
The structural columns of the B2t are gray*?
capped, hard when dry, and exhibit few roots or pores in the dense inter­
ior.
Gypsum crystals are found in the C horizon about 2 feet below the
soil surface.
Thoeny loams are well drained with medium to slow infil­
tration and runoff.
I/
Permeability is very slow.
See Appendix Table I for complete list of common and latin names.
=>IOo
Scobey loams occur on areas with 4 to 8 percent slopes.
These soils
are classified in the fine; montmorillonitic family of Aridic Argi=
borolls.
Typically they have brown clay loam Ai blocky light clay B2t» B3ca
and G horizons.
There are many roots in the B2t which begins at a
depth of about 4 inches.
ly 14 to 16 inches.
Depth to the prominent ca horizon is common­
Scobey soils are well drained.
Runoff and perme­
ability are moderate.
The vegetation is very similar to that at Havre with the addition
of thickspike wheatgrass and Montana wheatgrass.
The lowland sites
support colonies of porcupine grass.
Norris Site.-
The experimental site is located approximately one-
half mile west of the Red Bluff Research Ranch headquarters and approxi­
mately one mile east of Norris9 Montana.
Annual precipitation averages
15.05 inches measured at ranch headquarters,
The dominant soil on the study site is tentatively identified as
Sappington loam.
This site is situated on a southeast-facing four per­
cent slope of an upland fan at an elevation of 4 S700 feet.
Like the
Telstad9 the Sappington is classified in the fine-Ioamy9 mixed family of
Aridic Argiborolls„
Although the sequence of horizons are very thin at
this site, sandy Ioam9 sandy clay Ioam9 clay loam and loamy sand occurs
below 40 inches.
A typifying profile has 2 inches of grayish brown loam
Al, underlain by 3 inches of clay loam B2t, 3 inches of light clay loam
-U BScaj 12 inches of silt loam Clca and 20 inches of sandy loam C2„
off is slow to medium.
Run­
Permeability is moderate.
The principal grass and grass-like species present on this foothill
grassland range are needleandthread, blue grama, needleleaf sedge and
western wheatgrass.
A few remnants of bluebunch wheatgrass can be found.
Forbsj including clubmoss are Hoods phlox, hairy goldenaster, biscuitroot, American vetch, pussytoes, woolly Indianwheat, with tansy mustard
present on disturbed areas.
Among the shrubs, fringed sagewort is
common with an occasional plant of rubber rabbitbrush.
—CHEMICAL
—
—
—CONTROL.—
Initial herbicide screenings for clubmoss control were carried out
in the greenhouse on cores of clubmoss sod (Wagner, 1966).
Herbicides
showing clubmoss control were further trested in the field at the Havre
and Norris sites in the spring of 1964.
Trials were conducted using
plots 8% X 16% feet with treatments applied in triplicate using a ran­
domized block design.
The third site (Glasgow) was added in the fall
of 1964 using plots 8% X 33 feet (Wagner, 1966).
Following observations
of the 1964 treatments seven chemicals were
selected for further trials in the spring
of 1965 at all three locations.
AMS, momuron, atrazine and picloram were applied at Norris on April 22,
at Havre on May 21 and at Glasgow on May 22.
Paraquat, diquat and
endothall were applied at Norris on June 18, at Glasgow on June 22 and
Havre on June 23, 1965.
Surfactant Ortho X-77 was added to paraquat
a 12=
spray solution.
Additional applications of AMS, atrazine, monuron and
paraquat were made at all three locations in the fall of 1965 to plots
8% X 33 feet in size following the same procedures.
Treatments were ap=
plied at Norris November 11, Havre October 30 and Glasgow October 31,
1965,
Nitrogen fertilizer was included as an additional variable applied
to One=Iialf (8% X 16 feet) of each plot at a rate of 50 pounds N per
acre in the form of granular ammonium nitrate.
After evaluation of all 1964 and 1965 treatments, plots 40 X 60 feet
were treated in the spring of 1966 with what was thought to be optimum
rates of AMS, atrazine, monuron and paraquat.
Applications were made at
two locations = Havre March 24 and Norris March 28,
Nitrogen at 50 lbs.
N per acre was applied to half (20 X 60 feet) of each plot.
On June 15, 1966 at Norris an additional test was established on
plots 8% X 16% feet to evaluate spray surfactants.
Spray surfactants
are designed to increase the wetting, spreading and sticking of pesticide
sprays on plant surfaces and thus enhance herbieidal activity.(Jensen,
1964).
Two surfactants were used ~ Ortho X=77 and DuPont Spreader
Sticker,
paraquat.
In this test X = 77 at .5 percent by volume was combined with
DuPont Spreader Sticker at .5 percent was combined with lower
rates of AMS and monuron treatments.
In May, 1968 further trials were established at Norris on rod square
plots to evaluate effectiveness of spray adjuvants with lower rates of
AMS, atrazine and monuron.
DuPont Spreader Sticker was combined with AMS
“ 13=*
at the rate of .126 percent by volume.
DuPont T=MULZ AOZ emulsifier
formulated by Thompson Hayward Chemical Company especially for use with
atrazine was used at I percent by volume with atrazine.
DuPont surfacfe™
ant W-K was combined with monuron at the rate of .5 percent by volume.
All spray applications were made with a compressed air sprayer us­
ing 40 gallons of water per acre as the carrier.
Applications to small
plots (less than 40 X 60 feet) were made putting water and chemical for
one plot into a sprayer equipped with a single teejet nozzle.
The
entire plot was sprayed twice^ first in one direction then in the other.
Large plots (40 X 60 feet) were treated with a hand carried 8 foot boom
equipped with nine teejet nozzles and constant air pressure.
Application
rate on the large plots was controlled by length of spraying time.
Plots were visually evaluated at least twice during each growing
season to determine the response of clubmoss to the herbieidal treat­
ments.
All evaluations were made by the same person and were generally
made following a rain when clubmoss was in a period of active growth.
Comparisons were made between the amount of green clubmoss present on
the untreated check plots and the chemically treated plots.
Results
were tabulated for each plot based on G for no control to 100 for com­
plete clubmoss control.
Mosts but not all9 treatments were evaluated (for effects on
vegetational production) by hand Clippings usually in early August.
Yield samples included all vegetation except clubmoss.
The vegetation
-14"
was clipped at ground level from a 2 square foot circular plot and sepa­
rated by species groups to sample herbicidal affect on herbage yield.
The 8% X 16% feet plots were sampled at two locations and the 8% X 33
feet plots at Glasgow were sampled at three locations.
When nitrogen
was applied to half of the 8% X 33 feet plots the plots were sampled at
four locations.
Ten locations were sampled on the 40 X 60 feet plots.
Where nitrogen was applied half of the samples were from the nitrogen
treated portion of the plot.
Sampling locations within plots were
changed each growing season..
NITROGEN-WATER.°
Treatments consisting of four levels of nitrogen and four levels of
water were made in a split plot randomized block design.
Rates of 0, 50,
100 and 150 pounds of nitrogen per acre were applied to square rod plots
in triplicate May 27, 1965.
Sub-plots consisting of four levels of water were obtained by using
metal strips 6 inches wide and formed into rings 2 feet in diameter
which were driven 2 inches into the ground.
each water level on each nitrogen plot.
Two rings were used for
Water was added weekly from
June Il8 1965 to September 9, 1965 and May I, 1966 to August I, 1966 to
supplement natural precipitation with enough water to reach one-half,
I and 2 inches per week.
Yield response was sampled by removing the metal strips and clip­
ping at ground level all vegetation except clubmoss.
in August of 1965 and 1966.
Harvests were made
RESULTS AND DISCUSSION
Preliminary chemical screening trials were conducted on clubmoss sod
in the greenhouse.
Results of these trials are reported in detail by
Wagner (1966),
In the spring of 1964 those herbicides showing activity in the
greenhouse were submitted to field trials for further evaluation on
plots established at Norris and Havre,
Several chemical treatments in­
cluding AMSs atrazine and monuron killed all clubmoss at both locations.
Significant yield increases were reported for some of these treatments at
Norris in 1964 (Wagners 1966),
CLUBMOSS CONTROL.No herbicide has been registered by the USDA for selective control
of clubmoss,
At the time of this writing a petition requesting approval
of atrazine for this purpose has been submitted to the USDA.
It is hoped
that like action can be taken with AMS and monuron in the near future.
Response of clubmoss to treatments applied in the spring of 1964
varied from O to 100 percent control.
Based on evaluations made during
the summer of 1964 some chemicals were eliminated (Appendix Table 3).
Eight chemicals were selected for further testing (Table 2),
They all
proved to be effective under certain circumstances^ however, due to the
inconsistent results obtained or to cost relationships, dicamba, diquat,
endothall and picloram were dropped from further testing in the fall of
1965.
Table 2.
Percent clubmoss control in June, 1967 from herbicidal applications at Glasgow,
Havre and Norris for treatments made during 1964;"1965 and the spring of 196614
Chemical
AMS
Atrazine
Rate
Ib/A
5.0"
7.5
10.0
20.0
1.0
Spring
1964
Hl/ N
%
%
G
%
23
98
28
90
88
50
100
78
18
20
3
85
38
40
95
100
100
100
100
48
88
100
100
100
30
83
100
%
Time of Application
Spring
1965
N
H
N
G
G
%
%
%
'%
%
3
3
Fall
1964
H
70
37
Diquat
Ehdothall
Monuron
2.0
1.5
3.0
:5
1.0
3;o
i;o
45
78
38
15
78
10
13
50
70
87
100
58
72
89
37
97
98
93
93
10
10
62
3
4
100
3
0
42
97
100
100
2:o
Paraquat!/
Picloram
......
—
N
%
7o
85
93
70
74
70
97
100
38
53
60
93
20
25
65
83
98
100
97
100
28
80
8
90
0
37
7
90
46
80
100
92
100
100
100
100
12
13
15
35
35
25
48
48
95
16
53
18
80
93
88
100
100
100
100
73
90
100
70
85
70
68
48
100
18
55
63
33
40
i:5
4.0
.5
1.0
.5
1.0
2.0
27
67
53
93
10
50
Spring
1966
H
N
•%
%
13
i;s
Dicamba
Fall
1965
H
.
JL/ Average of three replications from observations in June, 1967»
l / G - Glasgow, H - Havre, N - Norris
JB/ Surfactant Ortho
77, I percent by volume.
Ave,
%
25
75
66
85
53
61
89
5
22
22
46
15
77
90
99
100
37
63
42
66
100
=17=
A 10 Ib/A rate of AMS averaged 66 percent clubmoss control in the
11 trials in which it was included (Table 2).
It is not known why poor
results were obtained in approximately 25 percent of the trials since
they were not necessarily associated with date of application or loca­
tion of treatments and since higher percent kill was obtained from
several applications at lower, rates.
AMS in excess of 10 Ibs/A produced
slightly better clubmoss control, however, such increases were not ■
justified by the increased chemical cost.
Results from the inclusion of DuPont Chemical Company° s Spreader
Sticker with AMS at Norris were disappointing (Table 3).
Excellent
results were obtained from the 1966 treatments; however, there was no
apparent advantage obtained from the Spreader Sticker in 1968.
Possibly
the lack of favorable response to surfactant was due to a reduced rate
(from .5 to .126 percent by volume).
Clubmoss control at the 2 Ib/A fate of atrazine averaged 89 per­
cent in the 14 trials which it was used (Table 2).
2 Ibs/A results were generally not satisfactory.
At less than
Results from the I
pound rate varied by location with control highest at Norris and lowest
at Havre.
Even at the 2 pound rate clubmoss kill was only 63 percent at
Havre from the fall applications (1964. and 1965), possibly due to inter­
ception of the chemical by the large amounts of vegetative residue on the
soil surface.
I
r
-1 V
r
Table 3.
Chemical
AMS-
Percent clubmoss control from treatments made at Norris with and without
surfactants!/.
Treatment Date
Previous Spring Application
June, 1966
May, 1968
without surfactant
without
with
without
with
Rate 1964
1965
1966
Ave,
Surfactant Surfactant— 'Surfactant Surfactant
Ibs/A
7.
Z=
; ?=
7,
7=
V"
7.
7=
13
5
7.5
10
Atrazine
Monuron
Paraquat
13
97
38
68
I
2
88
100
93
100
100
91
100
I
2
95
100
90
100
100
93
100
.25
.50
.75
100
88
100
100
100
97
100
60
12
40
40
40
42
82
88
43
100
95
100
96
100
100
100
I/
Average of three replications.
-treatments.
Observations made in 1967 except in 1969 on May, 1968
2/
X=77 .5"percent by volume with paraquat; DuPont Spreader Sticker, .5 percent with AMS
and. monuron.
2/
AMS - DuPont Spreader Sticker .126 percent by volume.
Atrazihe = T=MULZ A02 I percent by volume.
Monuron = DuPont Surfactant W=?K .5 percent by volume.
“
19
”
One percent by volume TaMULZ=AO2 emulsifier was used in May, 1968
with atrazine at Norris.
It resulted in slight bleaching of the vege=
tation a few days after treatment.
While the 95 percent control re=
suiting from I Ib/A was more than twice as high as that obtained with=
out surfactants it was not different from the results without surfactant
in 1964 and 1965 (Table 3).
The 43 percent control without surfactant
was the poorest results ever obtained at Norris with any rate of
atrazine.
Excellent elubmoss control was obtained with 2 Ibs/A of monuron.
Fifteen applications, over a four=year period, resulted in an average
control of 99 percent (Tables 2 and 3).
Twelve applications at the I
pound rate averaged 78 percent control although three treatments, fall
of 1964 at Glasgow and Havre and the fall of 1965 at Havre, gave only
about 50 percent control.
The excellent results obtained in June, 1966 and May, 1968 both
with and without surfactants at the I Ib/A level indicated a lower rate
of monuron should have been used to determine the effectiveness of sur=
factants with monuron at Norris (Table 3).
Paraquat supplemented with Ortho X=77 surfactant was generally less
ieffective than AMS, atrazine or monuron although at the I Ib/A rate
paraquat did give complete elubmoss control under certain undefined
conditions.
A paraquat treatment to be comparable in cost to the 2
pound rates of atrazine or monuron should not exceed .5 pounds per
=20=
acre.
Nine treatments made at this rate averaged only 37 percent club-
moss control (Tables 2 and 3),
Clubmoss control with picloram was generally good with the I or 2
Ib/A rate.
Cost of such treatments precluded further testing of this
chemical.
Diquat was generally less effective than paraquat in selectively
controlling clubmoss.
Dicamba and endothall were eliminated from further
tests due to the poor response of clubmoss.
Herbage Yields.During the course of these investigations, herbage yields from the
untreated check plots varied considerably.
Differences between years
was at least in part due to amount and distribution of precipitation
which was considerably below normal in 1966 and 1967 at Havre, and at
Glasgow in 1967.
Above normal precipitation was received at Glasgow and
Havre in 1965 and at Norris in 1967.
Monthly precipitation figures for
each year of the study are shown in the Appendix (Table 4) for each loca­
tion.
Differences in yield within years among untreated check plots at
each location was at least partially due to differences in distribution
patterns of individual species.
Because of this variation in check
yields, an average check for each year at each location was used to com­
pare most treatments (Table 4).
Since there was considerable range in
Table 4.
Pounds of dry matter produced by the untreated checks from, each test during
each year at each location.
Beginning of
Test
1965
Ib/A
Glasgow
1966
1967
Ib/A
Ib/A
Spring, 1964
Havre
1966
Ib/A
Voik
1964
Ib/A
9721/
425
462
320
1965
Ib/A
1967
Norris
1965
1966
Ib/A
Ib/A
1967
Ib/A
401
353
477
Fall, 1964
710
605
670
588
391
342
521
392
333
Spring, 1965
437
696
507
657
473
264
617
261
573
565
542
554
432
.300
421
494
303
369
397
Fall, 1965
Spring, 1966
Summer, 1966
Averages
585
574
622
573
739
467
Each yield is an average of three replications.
361
320
513
358
464
“
22
=
forage production, all yields are expressed as a percent of average check
for each year at each location,
(Tables 5, 6, 7, 8 and 9).
Herbage yields from all treatments shown in Tables 5, 6, 7, 8 and
9 were generally more than the average check.
Yields of vegetation
following treatments with dicamba, diquat, endothall and picloram were
not sampled as extensively as AMS, atrazine or monuron treatments due
either to poor clubmoss control or higher cost of obtaining similar re­
sults.
Individual trials were analyzed for significance using Duncan1s
Multiple Range Test (1955).
Comparisons of yields for 1965, 1966 and
1967 are shown in Tables 10, 11 and 12.
In 1965 significant differences were found in all six trials.
Yields significantly higher than untreated check occurred in three
trials - AMS 10 pound rate at Glasgow in the spring of 1965, paraquat 2
pound rate in the fall of 1964 at Havre, and atrazine I pound rate in
the spring of 1965 at Havre.
icantly lower than the check:
In two trials at Norris yields were signif­
Picloram granules at I pound rate in the
fall of 1964 and in the spring of 1965 by atrazine I pound, diquat I
pound, paraquat I pound, and picloram granules at I pound.
Yields did hot differ significantly in 1966 in any of the trials,
however, by the third growing season (1967) after treatment, 18 treat­
ments in five of the trials had significantly higher yields than the
Table 5.
Chemical
Herbage yields in 1964, 1965, 1966 and 1967 as a percent of average check follow­
ing herbicidal applications in the spring of 1964 at Havre and Norris for
selective control of clubmoss.
Rate
lb./A ..
I/
j2/
3/
7»
%
160
128
158
143
84
85
108
137
104
HO
104
123
143
122
163
189
224
127
140
160
139
120
126
62
144
97
94
77
158
123.
107
115
81
135
108
81
160
198
179
149
160
167
170
137
117
59
87
72
82
76
71
226
99
98
104
89
125
118
51
113
132
68
70
60
173
467
361
320
513
150
137
192
98
109
174
201
182
134
122
151
135
212
739
137
130
163
129
.85
HO
128
181
170
191
184
119
165
116
163
144
94
132
137
154
147
186
165
156
136
141
187
112
358
464
139
120
126
62
152
112
126
HO
117
59
87
72
82
76
71
226
125
118
148
94
117
146
126
148
133
95
HO
98
192
1967
%
HO
108
136
133
95
HO
116
122
162
146
177
186
172
127
140
160
162
120
135
130
88
134
122
118
154
192
172
152
148
154
178
124
Average of three replications expressed as a percent of the average check for each
year at each location,
Not harvested in 1964,
With surfactant X-77, I percent by volume,
-23
20
I
2
4
Dicamba
3
Iliquat
I
2
4
Endothall
1%
3
I
Monurqn
4
2
I
Paraquat^/
Picloram
.5
I
2
50
Nitrogen
Average Check Yields
in Ib/A
-
AMS
Atrazine
Herbage. YieldLas. Percent of Checki,/
Norris
Average
1964 1965 1966 1967
1964 1965 1966
%
%
%
%
%
%
%
%
Havre^V
1965 . 1966 1967
T a b l e '6.
Herbage yields in 1965, 1966 and 1967 as a percent of average check following
herbicidal applications in the fall of 1964 at Glasgow, Havre and Norris for
selective control of clubmoss.
Chemical
Rate
Ibs/A
Herbage Yield as Percent of Cheek!/
Glasg O W
Havre_____ _____ Norris_____ "____ Avi
1965 1966 1967 1965 1966 1967 1965 1966 1967 1965 1966
7o
7o
%
%
7.
7,
%
%
Zo
7,
7.
AMS
5
10
20
117
148
HO
135
126
147
87
114
125
115
130
119
82
111
115
122
121
161
78
87
87
113
94
112
105
116
98
103
122
105
HO
HO
125
105
117
128
I
2
138
116
170
141
137
132
106
106
98
105
137
158
90
86
130
139
150
182
111
103
133
128
141
157
1.5
3
97
103
131
104
103
87
94
109
122
Monuron
I
2
179
150
144
136
Picloram
h
I
HO
105
I
104
..
Atrazine
-
1967
7o
9
Dicamba
-
Picloram
granules
Average Check Yield
in Ibs/A
574
I/
76
97
92
140
89
82
150
158
128
HO
103
127
148
181
118
86
169
123
157
201
142
115
139
139
152
180
145
87
124
103
109
123
178
88
83
105
99
118
141
95
104
104
104
121
155
117
49
361
513
92
622
573
739
467
82
358
9
117
464
Average of three replications expressed as a percent of the average untreated check for
each year at each location.
Table 7.
Herbage yields in 1965$ 1966 and 1967 as a percent of average check following
herbicidal applications in the spring of 1965 at Glasgow, Havre and Norris
for selective control of clubmoss.
Chemical
Rate
Ib/A
Herbage Yield as Percent of Checkl./
Norris
Glasgow
Havre
1954 1966 1967 1965 1966 1967 1965 1966 1967
7,
%
%
7,
%
7,
7,
%
%
AMS
5
10
20
122
144
93
99
121
135
130
HO
124
133
100
102
142
172
157
104 . 90
166
95
152
118
99
108
104
144
171
182
115
113
101
113
134
132
126
149
153
I
2
90
79
134
129
116
160
151
95
167
187
126
191
122
65
122
133
222
187
121
80
141
150
155
179
181
214
83
79
89
170
138
138
83
79
89
170
133
166
150
173
165
232
95
98
115
133
114
212
108
99
138
145
136
181
169
139
186
226
100
154
179
147
74
145
361
513
Atrazine
.
Diquat
Monuron
I
2
Paraqua
.5
I
Piclofam
granules
91
147
%
I
I
119
99
2/
128
99
109
101
155
136
75
Average Check Yields
in Ibs/A
574
JL/
148
128
622
123
79
573
739
467
358
1965
7.
Average
1966 1967
7o
7,
164
180
76
464
Average of three replications expressed as a percent of the average check for each
year at each location.
With surfactant X=77, I percent by volume.
138
Herbage yields in 1966 and 1967 as a percent of average check following herbi=
cidal applications in the fall of 1965 at Glasgow, Havre and Norris for selec=
tive control of clubmoss,
Herbage Yield as a Percent of Check=/
.
Havre
Norris
Average
1966
1966
1966
1967
1967
1967
%
%
%
%
7o
7,
Chemical
Rate
Glasgow
1966
1967
%
%
AMS
7.5
10
126
127
94
92
108
182
172
150
138
103
181
136
124
137
149
126
Atrazine
I
1.5
2
109
108
HO
103
80
88
185
107
74
170
124
164
96
98
77
127
183
175
132
104
87
133
129
142
Monuron
I
1.5.
2
145
102.
102
98
84
106
136
191
124
144
195
236
112
102
96
181
186
190
131
132
107
141
155
177
Paraquat^/
.5
I
120
125
100
87
HO
135
135
108
163
99
94
140
131
120
101
112
622
573
467
361
358
464
482
466
Average Check Yields
in lbs/A
I/ Average of three replications expressed as a percent of the average untreated check
for each year at each location.
2! With surfactant X = 77, I percent by volume.
-
92=
Table 8.
Table 9.
Herbage yields in 1966 and 1967 as a percent of average cheek following herbi=
cidal applications in the spring of 1966 at Havre and Norris for selective
control of clubmoss,
Chemical
Rate
Ib/A
Glubmoss Controll/
Havre Norris Ave.
7,
. 7=
7,
Herbage Yield as Percent of Checki./
Havre
Norris
1966
1967
1966
1967
1966
1967
7.
7o
7,
7.
%
7,
AMS
10
100
38
69
138
207
HO
145
124
176
Atrazine
2
97
100
98
122
240
99
143
111
191
Monuron
2
100
100
100
115
192
68
146
92
169
Paraquat!./
.5
35
25
30
108
153
113
94
HO
123
467
361
358
464
412
412
Average Check Yields
in Ibs/A
I/
2/
3/
Average of three replications from observations in June 1967.
Average of three replications expressed as a percent of the average untreated check
for_each year at each location.
With surfactant X=77, I percent by volume.,
O
IS)
-28
Table 10.
Herbage yields in 1965, 1966 and 1967 following herbicidal
treatments at Glasgow in the fall of 1964 and spring of 1965
for selective control of clubmoss.
Chemical
Ra
Ibs/A
1965
Ibs/A
1966
Ibs/A
1967
Ibs/A
Fall, 1964
Check
AMS
Atrazine
Dicamba
Monuron
Picloram
Picloram granules
O
5
10
20
I
2
1.5
3
I
2
.5
I
I
710ab
669l/ab2/
852ab
632ab
790ab
663ab
555b
594b
1029a
864ab
633ab
600b
599b
605a
841a
774a
906a
1066a
922a
670ab
SOlbc
656ab
719ab
783ab
75 7ab
813a
899a
871a
860ab
906a
823ab
Spring. 1965
Check
AMS
Atrazine
Diquat
Monuron
Paraquat!/
Picloram granules.
I/
_2/
3/
O
5
10
20
I
2
.5
I
I
2
.5
I
I
437b
701ab
828a
5 3 lab
517ab
453b
696a
614a
753a
841a
833a
813a
682ab
567ab
920a
795a
802a
812a
431b
507d
742abcd
731bcd
71labcd
662abcd
917a
520cd
843ab
733abcd
562cd
870ab
782abc
703abcd
C
ABC
ABC
ABC
ABC
A
BC
ABC
ABC
ABC
AB
ABC
ABC
Average of three replications
Means with same letter are not significantly different; (Small
letter . P < .05, Large letter P < .01), using Duncan1s Multiple Range
Test. Comparisons can only be made within year of harvest and
treatment date.
With surfactant Ortho X-77, I percent by volume.
-29Table 11.
Herbage yields in 1965, 1966 and 1967 following herbicidal
treatments at Havre in the fall of 1964 and spring of 1965
for selective control of clubmoss.
Chemical
Rate
Ibs/A
1965
Ibs/A
1966
Ibs/A
1967
Ibs/A
Fall. 1964
Check
AMS
Atrazine
Dicamba
Monuron
Paraquat
Picloram
Picloram granules
O
5
10
20
I
2
1.5
3
I
2
2
.5
I
I
391a
588b
SSli/ab!/
385a
517a
958ab
537a
881ab
458a
782ab
489a
783ab
559b
428a
720ab
479a
9 5 Oab
593a
Sllab
1144a
. 535a
480a
646b
915ab
508
683ab
342a
442a
437a
582a
493a
570a
505a
536a
654a
449a
444a
643a
421a
Spring, 1965
Check
AMS
Atrazine
Diquat
Monuron
Paraquat!/
Picloram granules
I/
O
5
10
20
I
2.
,5
I
I
2
.5
I
I
657b
986ab
738ab
752ab
119a
702ab
803ab
748ab
586b
474a
665a
804a
734a
782a
876a
793a
700a
809a
792a
647a
264d
375cd
598abcd
548abcd
454bcd
69 Iabc
652abc
774ab
596abcd
838a
672abc
815a
529abcd
B
AB
AB
AB
AB
AB
AB
A
AB
A
AB
A
AB
Average of three replications
2! Means with same letter are not signifnicantly different; (Small
^3/
letter P < .05, Large letter P«< .01), using Duncan's Multiple Range
Test. Comparisons can only be made within year of harvest and
treatment date.
With surfactant Ortho X=77, I percent by volume.
-30Table 12,
Herbage yields in 1965» 1966 and 1967 following herbicidal
treatments at Norris ,in the fall of 1964 and spring of 1965
for selective control of clubmoss,
Chemical
Rate
Ibs/A
1965
Ibs/A
1966
Ibs/A
1967
Ibs/A
Fall, 1964
Check
AMS
Atrazine
Dicamba
Monuron
Picloram
Picloram granules
O
5
10
20
I
2
1,5
3
I
2
.5
I
I
521a
403l/ab2/
448ab
448ab
462a
439ab
455ab
419ab
604a
441a
452ab
426ab
251b
392a
405a
334a
403a
465a
497a
333f
489def
539cdef
455ef
697bcd
846ab
CD
BCD
CD
ABC
AB
376a
602a
441a
377a
355a
472def
730abc
933a
549cdef
654bcde
CD
ABC
A
BCD
ABCD
Spring, 1965
Check
AMS
Atrazine
Diquat
Monuron
Paraquat^/
Picloram granules
JV
2/
J3/
O
5
10
20
I
2
.5
I
I
2
.5
I
I
618a
464ab
485ab
606a
628a
336b
427ab
404b
486ab
505ab
515ab
342b
381b
261a
356a
387a
372a
435a
477a
318a
410a
477a
384a
480a
573de
668cde
793abcde
843abcd
1031a
866abc
641cde
638cde
528e
983ab
714cde
829abcd
675cde
C
ABC
ABC
ABC
A
ABC
BC
BC
C
AB
ABC
ABC
ABC
Average of three replications,
Means with same letter are not significantly different; (Small
letter P<,05» large letter P<C,01), using Duncan0s Multiple Range.
Test. Comparisons can only be made within year of harvest apd'
treatment date.
With surfactant Ortho X<=77s I percent by volume.
“ Sl-
un treated check.
These included the atrazine, diquat, monuron, paraquat
and piclorpm treatments.
Average yields for all applications of AMS IG pound rate8 atrazine
2 pound rate, and monuron 2 pound rate at all three locations the first,
second, third and fourth growing seasons after applications are given in
Table 13 and Figure I.
Average herbage yields from AMS treated plots showed an increase
over untreated check the first growing season following treatment for
every test conducted except for those established in the fall of 1964
and the spring of 1965 at Norris.
This was probably due to the greater
: selectivity AMS had for the grasses and forbs and for their immediate
response to reduced clubmoss competition.
Yields continued to increase
through the third growing season, however not as rapidly as those follow­
ing atrazine and monuron treatments (Figure I).
Yields the first growing season following treatment with atrazine
and monuron were generally lower than for AMS.
Monuron appeared to be
slightly less injurious than atrazine (Figure I).
Greatest increase in
herbage production from atrazine and monuron treatments occurred during
the second growing season.
Yields continued to increase through the
fourth growing season (1967) at which time forage sampling ended.
Paraquat at .5 pound per acre with Ortho X-77 surfactant produced
herbage yields similar to the 10 pound rate of AMS or the 2 pound rates
of atrazine or monuron for the first two growing seasons following treat-
Table 13.
Location
Herbage yields expressed as percent of check the first, second, third and fourth
growing seasons after treatment with AMS 10, atrazine 2, monuron 2, and paraquat
.5 Ibs/A applied for selective control of clubmoss,
Harvest
year
after
Treatment
AMS 10 lbs/A
No. of
Treat.
% of
Check
Ave.-/
Atrazine 2 Ibs/A Monuron 2 Ibs/A
No. of
No. of
7= of
Treat.
7. of
Treat.
Check
Ave=JL/. Check
Ave.-/
Paraquat .5 Ib/A
No. of
7. of
Treat.
Ave.I/
Check
Norris
I '
2
3
4
98
121
144
4
4
2
82
137
178
191
4
5
3
I
87
141
192
165
4
5
3
I
125
94
154
3
2
I
Havre
I
2
3
4
138
160
144
4
4
2
99
171
152
. 163
4
5
3
I
113
182
1.73
179
4
5
3
I
109
152
186
2
3
I
Glasgow
I
2
3
4
140
113
112
3
3
2
100
119
146
3
3
2
117
124
128
3
3
2
120
100
155
I
I
I
Ave. of all
Locations
I
2
3
4
125
131.
133
31/
3
3
94
142
159
177
3
3
3
2
106
149
164
172
3
3
3
2
118
115
165
3
3
3
JL/
2/
Average from number of tests indicated with each test consisting of three replications.
Average from number of locations where tests were conducted.
6
W
ro
0
-33AMS
______
Atrazine -----Monuron _______
Norris
Havre
200-
200Yield % of Ave. Check
190-
£
9080-
Growing Seasons After
Treatment
Yield % of Ave. Check
Glasgow
____________ ____
1
2
3
4
Growing Seasons After
Treatment
Average of all Locations
200-
200-
190180170160150-
^ 190cu 180-
/
' S ---
80-______ ________________
1
2
3
4
Growing Seasons After
Treatment
Figure I.
801
2
3
4
Growing Seasons After
Treatment
Herbage yields expressed as percent of check the 1st, 2nd,
3rd and 4th growing seasons after treatments with AMS 10,
atrazine 2, and monuron 2 Ibs/a applied for selective con­
trol of clubmoss.
-34-
ment.
Paraquat, a contact type herbicide was less injurious to the
vegetation when applied during dormancy.
Species Response to Herbicides.There was a significant species X treatment.interaction.
for this reason that each species is. discussed separately.
that contributed the most
response
It was
The species
to this interaction was needleand-
thread which is the dominant species at both Havre and Norris (Tables
14, 15, 16 and 17).
Response of needleandthread following the fall 1964 and spring 1965
treatments showed paraquat 2 and picloram I Ib/A at Havre from the fall
'k-
L
1964 applications as the only two treatments with yield significantly
higher than the check plots in the 1965 harvest.
By 1967, even though
yields on the untreated check plots were lower, yields on several of the
herbicide treatments had increased.
Treatments of AMS, atrazine, monu-
ron, picloram, diquat and paraquat all showed yields significantly
higher than the untreated plots.
Yields of blue grama were of minor importance at both Havre and
Norris.
In 1967 at Havre yields were near zero on the check plots and
less than 50 Ibs/A on most herbicidal treatments.
Yields at Norris were
also quite low, however, there was some response to treatments.
Signifi=
cant increases in blue grama occurred on plots treated with atrazine
and monuron compared to no increase on the untreated check plots (Tables
16 and 17).
Table 14.
Chemical
and Rate
Ibs/A
Yields of blue grama, needleandthread, prairie junegrass and forbs in 1965, 1966
and 1967 following herbicidal application at Havre in the fall of 1964, for
selective control of clubmdss.
Blue Grama
1965,
1966
1967
Ibs/A Ibs/A Ibs/A
22l/al/
Check
AMS
38b
5
24b
10
22b
20
Atrazine
24b
I
IOOa
2
Dicamba
17b
. 1.5
15b
3
Monuron .
34b
I
43ab
2
Paraquat
2
Sb
Picloram
.5
40ab
I
Picloram
Granules'
14b
I
I/
27
3/
20a
Oa
22a
31a
17a
13a
7a
7a
17a
54a
Needleandthread
1965
1966
1967
Ibs/A Ibs/A Ibs/A
192a
Forbs
1966
Ibs/A
lbs/i
70bc
120bc
48a
1967
16a
5a
480abc 209a
379bc 234a
626abc 301a
74a
265bc
249bc 128a
366abc 58a
16a
42a
70a
22a
81a
104a
166abc 96bc
284a
149ab
75bc 104bc
55a
51a
56a
7a
31a
559abc 293a
421bc 346a
276bc
349abC
35a
62a
8a
24a
20a
38a
104abc 122bc
25bc
28bc
146a
62a
Na
16a
348bc
561abc
Na
124a
382abc 112a
Na
Na
Na
28a
26a
35a
15a
4a
537abc 324a
361bc 230a
3 70abc IlOa
423ab 112a
28a
27a
52a
97a
174abc 66bc
149abc 247a
36a
39a
IOa
la
803a
343a
349abc
69a
52a
52a
195ab
114bc
24a
32a
36a
9a
12a
475abq 369a
694ab 366a
343abc
493a
64a
96a
31a
56a
51a
93a
22bc
Oc
24bc
Oc
la
0a
Na
Na
210c
1965
Ibs/A
85a
NaV .
295c
Prairie Junegrass
1965
1966
1967
Ibs/A Ibs/A Ibs/A
6bc
Oc
Na
Na
Na
6a
434abc Na
245bc
85a
Na
28a
52bc
Na
Average of three replications.
Means with the same letter are not significantly different; (P~<.05) using Duncan's
Multiple Range Test. Comparisons are valid only within years by species.
Na = Not harvested.
Na
2a
Oa
Table 15»
Chemical
and Rate
Ibs/A
Yields of blue grama^ needleandthread, prairie junegrass and forbs in 1965s 1966
and 1967 following herbicidal applications at Havre.in the spring of 1965s for
selective control ofclubmoss,
Blue Grama
1965.
1966
1967
Ibs/A Ibs/A Ibs/A
Needleandthread
1965
1966
1967
Ibs/A Ibs/A Ibs/A
Prairie Junegrass
1965
1966
1967
Ibs/A Ibs/A Ibs/A
1965
Ibs/A
Forbs
1966
Ibs/A
1967
Ibs/A
129a
9a
2a
421a
361a
13a
219f
66ab
52b
28b
26l/al/ 33a
Cheek
AMS
606a
480a
166a
31a
52a
64a
29a
12a
236f
84a
66ab
5
64ab
79a
15a
27a
513a
659a
46a
29a
49Oede 115a
10
27abe 52ab
16h.
476a
486a
98a
87a
Ida
92a
42a
395de 174a
20
31abe 15b
41b
Atrazine
36a
609a
13a
14a
93a
52a
757a
361ef 159a
I
42abc 102ab
31b.
583a
690a
4a
59a
177a
28a
9a
2
602abe 41a
19bc
lb
50b
Diquat
Na
Na
Na
3a
Na
498ede Na
Na
41a
Na
.5
Na
99ab:
Na
Na
19a
Na
Na
Na
72a
Na
I
605abc Na
Na
62ab
Monuron
6a
537a
80a
21a
31a
13a
653bcd 536bcd 87a
I
9b
55abc
13b
81a
85a
69a
600a
544a
719a
39a
28a
IOa
2
9be 151a
27b
Paraquat
Na
43a
51a
Na
651a
Na
47a
28a
383de
,5
Na
23b
208a
Na
48a
27a
Na
493a
Na
24a
I
6 7lab
76a
Na
53ab
20b
Picloram
Granules
38a
Na
8a
408a
Na
Na
394de 123a
124a
I
Oc
Na
Ob
I/ Average of three replications
2/ Means with the same letter are not significantly different; ( P C , 05) using Duncan°s
Multiple Range Test, Comparisons are valid only within years by species,
jj/ Na = Not harvested.
Table 16.
Chemical
and Rate
Ibs/A
Yields of blue grama, needleandthread, M i s c . grasses (annual and perennial) and
forbs in 1965, 1966 and 1967 following herbicide application at Norris in the
fall of 1964, for selective control of clubmoss.
Blue Grama
1966
1965.
1967
Ibs/A Ibs/A Ibs/A
Misc . Grasses
Needleandthread
1965
1966
1965
1966
1967
1967
Ibs/A Ibs/A Ibs/A . Ibs/A Ibs/A Ibs/A
1965
Ibs/A
236a
130a
68a
5&l/b c 45b2/ 30b
197de 105a
35b
Check
99abcd
AMS
32a
30b
48b
40b
53ab 223ab 133a
253cde Ila
126ab
5
168a
45a
10
55b
56ab
83ab 157ab
322bc
29a
33b
147a
64ab
42b
4 lab 125ab 124a
81a
112a
105b
20
187de
73abcd
Atrazine
48b
36a
27a
SOab
105ab 199ab 225a
397ab
33b
I
124abc
84ab
90a
103ab 176ab 261a
471a
51a
35a
139b
2
32bcd
Dicamba
Na
Na
178ab
Na
Na
125a
Na
Na
86ab
20d
1.5
Na
Na
45b
Na
73ab 184ab
192e
126a
119b
3
23cd
Monuron
89a
71ab 217ab 297a
78a
250a
80ab
303bcd 70a
135a
I
203ab 188a
471a
47a
119a
2
IOOab
53ab 182a
79b
83abcd
Picloram
86ab
249cde 84a
48a
99b
66ab IOlab 214ab 233a
.5
19d
175a
415ab
62ab
29b
85ab 234a
78a
124a
108b
4d
I
Picloram
Granules
120a
Na
Na
89b
Na
Na
Na
Na
38a
Id
I
I/ Average of three replications.
2/ Means with the same letter are not significantly different; (P<»05) using
Multiple Range Test. Comparisons are valid only within years by species.
2/ Na - Not harvested.
Forbs
1966
Ibs/A
1967
Ibs/A
130ab
56ab
181a
135ab
51bc
83ab.
97abc 59ab
119abc 129ab
IObc
64ab
Na
Na
Na
25c
75abc 54b
24bc 153a
15bc
Ic
58ab
15c
Na
Na
Duncan's
Table 17.
Yields of blue grama, needleandthread, raise, grasses (annual and perennial) and
forbs in 1964, 1966 and 1967 following herbicidal application at Norris in the
spring of 1965, for selective control of clubmoss.
Chemical
Blue Grama
1966
1967
and Rate 1965.
Ibs/A . Ibs/A Ibs/A Ibs/A
Needleandthread
1965
1966
1967
Ibs/A Ibs/A Ibs/A
Misc . Grasses
1965
1966
1967
Ibs/A Ibs/A Ibs/A
1965
Ibs/A
Forbs
1966
Ibs/A
1967
Ibs/A
M
O
VO
5O
49a
158e
93b
59i/bc 39a2/ 78ab 190ab 100a
163bc 196ab
43a 159bcd
Check
AMS
39a
36a
83ab 188ab 127a
287cde 60b
106c
89abc 122a 149bcd
5
50c
45a
166a
42a
37b
139b
303bcd 64b
10
159bc 187ab
78a 238abc
52c
55a
72ab 172ab 130a
258bcde 179a
78a
370a
20
56c
137abc 51a 106cd
Atrazine
510a
70a
190a
56b
49a
138a
132ab 212a
275ab 145abc 41a
I
58d
57a
304a
363b
121ab 128b
61b
18a
2
56c
99c
49bc
69a. 244ab
Diquat
Na
39b
182b
-Na
352bc
57b
Na
.5
49c
77c
89abc Na
140bcd
59a
290bcde 44b
34a
123ab 154ab 148a
I
62bc
86c
117abc 40a 102d
Monuron
60a
70ab 197ab 122a
174de
57b
52a
143a I37bcd
I
72bc
108c
74a
506a
9 lab 147ab 212a
48b
36a
230a
2
57c
107c
124a 265ab
Paraqua t
68a
140a
129b
109a
279bcde 30b
67a
68bc
.5
107c ' 256a
92a 167bcd
66a
140a
118ab
174a
224cde 36b
30c
21a
I
105c
142abc 155a 300a
Pieloram
Na
Na
112ab 158ab
197de
69bc
77b
317a
Na
I
Ic
Na
36d
JL/ Average of three replications.
2/ Means with the same letter are not significantly different; ( P < .05) using Duncan's
Multiple Range Test. Comparisons are valid only within years by species,
3/ Na - Not harvested.
-39-
Prairie jUtiegrasss, a species separation at Havre, like blue grama
was of minor importance in pounds of forage produced (Tables 14 and 15).
There were considerable differences in yields but no significant dif­
ferences were found among treatments.
Distribution of forbs was irregular leading to large fluctuations
in yields.
Some increases in yield of forbs occurred following applica­
tions of AMS, mbnuron and paraquat.
Complete kill of forbs resulted
from applications of picloram.
Herbicide Effects on Fringed Sagewort.Fringed sagewort, a widely distributed range plant is increasing
in many areas of the state.
It was especially prevalent at both the
Glasgow and Havre experimental sites.
While present at Norris, the
stand was of minor importance.
Fringed sagewort was separated during the harvest at. Glasgow.
Yields ranged from zero where it was controlled by treatments of atrazine, monuron and picloram to over 300 pounds per acre (Table 18).
All
atrazine, monuron and picloram treatments greatly reduced yields of
fringed sagewort.
However, AMS had no effect on this species.
Visual
observations since 1967 at the treatment site indicate fringed sagewort
seedlings may reinvade treated areas two or more years after treatment.
Chemical-Nitrogen Interaction.The immediate response that some vegetation showed to clubmoss con­
trol does not appear to be entirely due to reduced competition for water.
-40Table 18,
Yield of fringed sagewort in 1967 at Glasgow following appli­
cations of herbicides at various times for control of club-
mossl/.
Chemical
Rate
Ibs/A
-
Check
5
7.5
10
20
AMS
Atrazine
.
I
1.5
2
Fall
1964
Ibs/A
Time of Treatment
Fall
Spring
1965
. 1965
Ibs/A
lbs/A
. 30
56
I
33
67
23
54
20
I
3
0
0
I
1.5
2
7
0
0
0
Picloram
I
0
0
Paraquat
•.5
Monuron
I/
■
325
Average of three replications for each treatment.
Ave..
Ibs/A
32
39
39
8
17
39
43
22
I
2
0
2
2
0
11
6
4
6
6
I
0
2
164
”41-
To determine if nitrogen in combination with herbicidal treatments woyld
provide an added increase in vegetation production over that obtained
with either herbicide or nitrogen alone, a 50 pounds per acre rate of
nitrogen was applied with all herbicidal treatments in a split plot
design on all treatments made in the fall of 1965 and the spring of
1966.
Herbage yields in general increased in 1966 and 1967 following
herbicide and nitrogen applications.
Increased yields in 1966 were due
primarily to the addition of nitrogen (Table 19).
However, by 1967 the
vegetation had recovered from initial herbicidal injury and vegetation
yields increased for all treatments.
Increased growth was further ob­
served ("yield was not measured) in 1968 and 1969.
In general, both
nitrogen and herbicide treatments increased vegetation yields.
Yields measured in 1967 from treatments applied in the fall of 1965
are presented in Table 20 for Havre and Norris.
Data was analyzed to
determine if the addition of nitrogen significantly increased the vege­
tation over herbicidal treatments alone.
Significant increases occurred
at Havre on six of 11 treatments consisting of check, atrazine, monuron
and paraquat treatments.
Yields were significantly increased with nitro­
gen in five of 11 treatments involving AMS, atrazine and monuron.
Individual species reacted differently to the addition of nitrogen
(Table 21).
Nitrogen significantly increased the yields of needleand-
thread at both Havre and Norris.
Miscellaneous grasses and forbs also
-42-
Table 19.
Yields as
plication
Norris in
spring of
Chemical
a percent of check in 1966 and 1967 following ap­
of herbicides and nitrogen at Glasgow, Havre and
the fall of 1965 and Havre and Norris in the
1966.
Rate
Ibs/A
0 Nitrogen
1966
1967
%
%
O
100
100
Nitrogen
50
*==
AMS
10
113
Atrazine
2
Monuron
Paraquat
Check
Check
Check - Nitrogen
I/
2/
3/
50 Ibs/A Nitrogen
1966
1967
%
%
100
100
149
181
150
161
235
97
165
119
250
2
95
181
133
250
.5
95
119
132
210
479
Ibs/A
412
Ibs/A
479
Ibs/A
412
Ibs/A
714
Ibs/A
746
Ibs/A
*”*=•
Nitrogen and herbicidal treatments applied in a split design with
nitrogen as the main plot.
Average of three replications from each of the five tests in percent
of average check for each year and nitrogen treatment.
X-77 surfactant used at I percent by volume.
-43=
Table 20.
Herbicide
Effects of several herbicides and 50 Ibs/A nitrogen on her­
bage yields following applications at Havre and Norris in
the fall of 19651/.
Rate
Ibs/A
4322/bl/
816a
625b
421a
780a
0
50
620a
890a
755b
841a
1128a
985abc
10
0
50
540a
843a
692b
633b
1301a
967abc
I
0
50
613a
900a
754b
590b
1457a
1024ab
1.5
0
50
448b
1086a
767b
851a
1271a
1024ab
2
0
50
592a
849a
720b
811b
1363a
1087a
I.
0
50
521a
779a
650b
841b
1607a
1224a
1.5
0
50
704b
1048a
876ab
864b
1568a
1216a
2
0
50
852b
1283a
1068a
883a
981a
932abc
0
50
488b
925a
707b
436a
905a
671bc
0
50
391b
913a
652b
651a
1060a
7.5
Atrazine
Monuron
Paraquat!/
.5
I
J./
2V
4/
Norris
with &
Treatment
without N
Means
Ibs/A
Ibs/A
0
50
Check
AMS
Nitrogen
Ibs/A
Havre
with &
Treatment
without N
Means
Ibs/A
Ibs/A
601c
,
856abc
Nitrogen and herbicidal treatments applied in a split plot design
with nitrogen as the main plot.
Average of three replications.
Means with and without nitrogen within treatment and treatment means
followed by the same letter are not significantly different (P"<.05)
using Duncan"s Multiple Range Test.
X-77 surfactant used at I percent by volume.
-44-
Table 21.
Effects of nitrogen on several species of herbage with all
herbicides combined for treatments made in the fall of 1965
at Havre and Norrisl./.
Species
Nitrogen
Ibs/A
Havre
Species
with &
without N
Means
Ibs/A
Ibs/A
142/a3/
13a
14c
6
.50
36a
33a
35bc
Needleandthread
0
50
439b.
763a
Western wheatgrass
6
50
Blue grama
0
50
Prairie junegrass
.
-
24a
'5 la
601a
0
50
Forbs
0
50
I/
ImI
J3/
92a
103a
98c
17a
19a
I8d
295b
568a
432a
139b '
231a
185b
3 8b c
Misc. grasses
0
(Annual & Perennial) 50
Needleleaf sedge
Norris
Species
with &
without N
Means
Ibs/A
Ibs/A
27a
55a
51a
80a
65b
142b
226a
41cd
184b
Nitrogen and herbicidal treatments applied in a split plot design
with nitrogen as the main plot at 50 Ibs/A.
Average of 11 treatments each with three replications.
Means with and without nitrogen within species and species means
followed by the same letter are not significantly•different (P<T.05)
using Duncan's Multiple Range Test.
-45-
increased significantly at Norris.
Other species were not significantly
affected by addition of nitrogen.
Nitrogen-Water.Vegetation in this test responded rapidly to both nitrogen and
water as evidenced by a change in color and by increased growth.
Herb­
age yields in 1965 ranged from 399 pounds per acre on the untreated to
1843 pounds per acre on plots receiving 2 inches of precipitation per
week and a 150 pound per acre nitrogen treatment (Table 22).
The 1966
yields were lower on all plots including the untreated check.
However,
there were still significant results from the added nitrogen and water.
One explanation for this decline in production is the possible injury to
the plants associated with harvesting the same both years by clipping at
ground level all vegetation except clubmoss.
Nitrogen significantly increased yields in both 1965 and 1966
(Table 23) although there were larger differences in 1965.
Addition of
water also showed significant effects on yield in both 1965 and 1966
(Table 24).
However, results were not as great from the addition of
water as from nitrogen.
Even though 1966 yields were lower than those obtained in 1965 the
response to both nitrogen and water were similar when compared to check
on a percentage basis (Table 25 and Figure 2).
the highest rate of water for unknown reasons.
An exception occurred at
=46=
Table 22.
Lbs. of
Nitrogen
Per Acre
Response of herbage to four levels of nitrogen and water on
clubmoss infested range for each of two years at Norrisl./.
Vegetation Yield±/
Year
0
Ibs/A
Moisture!/ (Inches)
I
%
lbs/A
lbs/A
2
lbs/A
1965
399h4/
43 Ogh
545fgh
546fgh
1966
191e
Slide
382cde
221e
1965
663efgh
612fgh
756defgh
840defg
1966
491cde
333de
409cde
334de
1965
816defh
874def
1078cde
1675ab
1966
668abcd
534bcde
1965
853defg
1094cd
1395bc
1966
658abcd
862ab
959a
o
50
.
100
741abc
592abcd
1843a
150
602abcd
1^/ Nitrogen and water treatments applied in a split plot design with
nitrogen as the main plots,, nitrogen applied in May9 1965.
2./ Average of three replications at each rate and year.
3/
4/
Water applied to subplots from June 11 to September 9, 1965 and from
May I to August Is 1966 to obtain weekly rates of:
Y
O = natural precipitation
.5 in. per week moisture
1.0 in. per week moisture
2.0 in. per week moisture.
Means followed by the same letter for the same year are not signifi­
cantly different; (P<1.05) using Duncan's Multiple Range Test.
=
Table 23.
1966
Ibs/A
48Q2/d2/
276b
50
718c
392b
100
Illlb
6344
150
1296a
771a
Table 24.
Effect of four levels of water applied during the growing
season.in 1965 and 1966 on herbage yield!/
Inches H 2O
per Week
Yield and Year
1965
Ibs/A
1966
Ibs/A
683?/cl/
502b
753c
438b
1.0
943b
510b
2.0
1226a
623a
<£/
.5
2/
4/
Yield and Year
1965
Ibs/A
0
2/
"
Response of herbage to four levels of nitrogen following ap­
plication in May, 1965 at NorrislA
Lbs, of Nitrogen
per Acre
I/
47
.
Nitrogen and water treatments applied in a split plot design with
nitrogen as the main plot with nitrogen being applied in May, 1965
and water applied weekly during the 1965 and 1966 growing season.
Average of 12 replications.
Means for the same subscript for the same year are not significantly
different; (P«<.05) using Duncan’s Multiple Range Test.
Water applied to subplots from June 11 to September 9, 1965 and
May I to August I, 1966 to obtain weekly rates of;
O = natural precipitation
.5 in. per week moisture
1.0 in. per week moisture
2.0 in. per week moisture.
=48™
Table 25.
Lbs. of
Nitrogen
per Acre
Herbage yields in 1965 and 1966 expressed as percent of
check following the applications of nitrogen and water at
Norrisl'.
YieldS./ as Percent of Check
Moisture!/ (Inches per Week)
I
h
%
7,
Year
0
%
2
7,
1965
100
108
137
137
1966
100
163
200
116
1965
166
153
189
211
1966
257
174
214
175
1965
205
219
270
420
1966
350
280
388
310
1965
214
274
350
462
1966
345
451
502
315
U
50
io o
150
I/
2/
3/
4/
Nitrogen and water treatments applied in a split plot design with
nitrogen as the main plot, nitrogen applied in May, 1965.
Average of three replications at each rate and year.
Water applied to subplots from June 11 to September 9, 1965 and from
May I to August I, 1966 to obtain weekly rates of:
0 = natural precipitation
.5 in. per week moisture
1.0 in. per week moisture
2.0 in. per week moisture.
Means followed by the same letter for the same year are not signif™
icantly different; (P<»05) using Duncan's Multiple Range Test.
500 1965 Yield
1966 Yield
400 Percent of Check
200
-
lbs. N/A
In. H20/Wk.
Figure 2.
50
100
0
150
100
.5
150
50
100
1.0
150
100
150
2.0
Herbage yields in 1965 and 1966 expressed as percent of check following the applica­
tion of nitrogen and water at Norris.
-50-
Not all species responded the same to the addition of nitrogen and
water.
The greatest increase in yield in 1966 was recorded for needle-
andthread; while the greatest decrease was shown by the forbs and shrubs
(Table 26).
Clubmoss was apparently not adversely affected by the addi­
tion of water during the two growing seasons.
There was no apparent
injury to clubmoss from nitrogen even at the 150 pound per acre level.
-51Table 26.
Lbs, of
Nitrogen
per Acre
Forage yield in 1965 and 1966 from the nitrogen-water treat­
ments at Norris for rieedleandthread and miscellaneous forbs
and shrubs.
Yieldl/and Moisture LevelZ/
Misc. Forbs and Shrubs
Needleandthread
I
2
0
I
%
%
2
in.
in.
in.
in.
in.
in.
in.
Year
_0
in.
1965
144
137
133
150
95
76
178
128
1966
80
107
163
87
45
89
51
37
1965
187
200
199
148
152
166
131
1966
200
200
158
155
172
52
35
40
23
1965
247
311
218
368
323
265
279
310
1966
343.
235
364
370
101
81
60
41
1965
324
338
308
430
310
269
269
365
1966
445
572
531
373
96
64
72
45
U
50
100
150
I/ Average of three replications.
2/
Average of three replications at each rate and year.
SUMMARY
Selective chemical control of clubmoss was studied at three loca­
tions involving 15 tests representing spring, summer and fall treatments
from 1964 through 1968.
Treatments were evaluated for percent clubmoss
control, for vegetational change, and for production of forage.
1.
AMS, atrazine and monuron were the most promising
herbicide treatments.
2.
Monuron at 2 pounds per acre gave the highest kill
of clubmoss (99 percent).
3.
Atrazine at 2 pounds per acre and AMS at 10 pounds
per acre generally gave satisfactory clubmoss control.
4.
Atrazine and monuron killed existing fringed sagewort
plants and prevented reinfestation for one or more
grazing seasons.
5.
Dead clubmoss decomposes very slowly leaving a dense,
compact sod resistant to wind and water erosion.
6.
Herbage yields continued to increase for four years
following application of AMS, atrazine and monuron.
7.
Addition of 50 Ibs/A nitrogen to atrazine and monuron
treatments increased the production of herbage over
herbicide treatment alone.
APPENDIX
■ -54"
Appendix Table I.
Plant names.
Common Names
Scientific NamesA/
GRASSES AND SEDGES:
Bluebunch wheatgrass.
Blue grama..........
Green needlegrass....
Montana wheatgrass...
Needleandthread.....
Plains reedgrass,....
Prairie junegrass....
Sandberg bluegrass...
Six-weeks fescue....
Thickspike wheatgrass
Threadleaf sedge.....
Western wheatgrass...
.Agropyron spicatum
.Bouteloua gracilis
.Stipa viridula
.Agropyron albicans
.Stipa comata
.Calamagrostis montanensis
.Koeleria cristata
.Poa secunda
.Festuca octoflora
.Agrqpyron dasystachyum
..Carex filifolia
.Agropyron smithii
FORES;
American vetch.....
Biscuitroot.......
Cudweed sagewort...
Green sagewort.....
Hairy goldenaster..
Hoods phlox........
Milkvetch..........
Penstemon..........
Pussytoes..........
Scarlet globemallow
Woolly Indianwheat.
Vicia americana
Lomatium spp
Artemisia ludoviciana
Artemisia dracunculoides
Chrysopsis villosa
Phlox hoodii
Astragalus spp
Penstemon albidus
Antennaria spp
Sphaeralcea coccinea
Plantago purshii
SHRUBS:
Broom snakeweed.....................Gutierrezia sarothrae
Fringed sagewort............. ...... Artemisia frigida
I/
Botanical names according to Booth, 1950 and Booth & Wright, 1962
-55-
Appendix Table 2.
Chemical names.
Chemical
Amitrole T
3-amino-l,2,4-triazole ammonium thiocyanate
AMS
Ammonium sulfamate
Atrazine
2-chloro-4?ethylamino-6-isopropylamino^s-triazine
Bromacil
5-bromo-3-sec-butyl-6-methyluracil
Dicamba
2-methoxy-3,6-dichlorobenzoic acid
Diquat
6,7-dihydrodipyrido (l,2-a:2',l,-c)pyrazidiinium
DNBP
4,6-dinitro-o-sec-butylphenol
Endothall
7-oxabicyclo(2.2.l)heptane-2,3-dicarboxylic acid
Fenac
2,3,6-trichlorophenylacetic acid
Fenuron
3-phenyl-l,I-dimethyIurea
Monuron
3-(p-chlorophenyl)-l,I-dimethylurea
Paraquat
I,I'-dimethyl-4,4'bipyridinium
Picloram
4-amino-3i5,6-trichloropicolinic acid
Propazine
2-chloro-4,6-bis(isopropylamino)-s-triazine
2,4,5-T
2,4,5-trichlorophenoxyacetic acid
2,3,6-TBA
2,3,6-trichlorobenzoic acid
56-
Appendix Table 3.
Chemical
Percent clubmoss control in June, 1967 on treatment
made in the spring o f 1964 at Havre and N o r r is J ;/.
Rate
Ibs/A
Havre
1.5
3
0
22
17
42
9
32
40
80
100
100
100
100
100
100
Atrazine
4
77
100
88
Bromacil
I
2
8
80
73
100
41
90
Diquat
2
4
25
95
65
98
45
97
DNBP
1.5
3
2
0
0
17
I
9
Endothall
1.5
0
12
6
Fenac
3
3
5
4
Fenuron
I
2
.4
2
7
. 40
15
30
100
9
19
70
Monuron
4
100
100
100
Nitrogen
50
0
0
0
Nitrogen 50 Ibs/A
+ 2,4,5-T .5 Ibs/A
50 4 .5
0
0
0
35
90
63
Amitrol-T
AMS
Ave.
%
Paraquat
I
Propazine
2
32
35
34
2,3,6-TBA
3
3
3
3
2,4,5-T
1.5
3
0
. 5
3
17
2
11
J./
■
%
Norris
7,
Average of three replications.
“57-
Appendix Table 4»
Precipitation measurements from the nearest!/ weather station for eadh experimental site.
Year
'1964
Month
G
in.
.in.
January
.21
February
,19
March
.61
April
.41
May
2.52
June
2,78
July
1.28
August
.85
September .52
October
.20
November
.26
December
,78
.31
.11
.22
1.71
2.44
1.12
1.49
.98
1.22
.00
.44
1.19
TOTAL
I/
10.53
H
11.23
;n .
in.
.06 .28
.33
1.62
2.83
4.20
.38
1.98
.02
.53
.93
.86
14.02
G
in.
1965
H
in.
1966
.N' _
in, .
I
.
!.
1967
G
in.
in.
N
in.
G
in.
in.
N
in.
H
H
Long Term
Average
H
G
in.
in.
N
in.
.46
.20
,30
.51
3,24
4.64
.91
3.01
,79
T
.12
.12
.64
.32
;40
1.46
.85
4.62
2.28
2.27
2.56
.04
.70
.29
.35
.09
.60
2.02
4.19
1.91
.65
.75
2.47
,72
.50
.60
,51
.14
.10
.59
1.91
.89
3.13
3.65
.41
.68
.34
.23
.53
,04
.17
.44
.30
2.60
1.80
.56
.20
1.02
.64
.22
.47
.43
.76
1,29
; 3.53
\ 1.95
| .29
1.21
1.30
1.20
1.34
30
.84
.25
.83
.84
.68
2.23
.12
.18
2.10
1.13
.36
.26
.45
.50
1.70
2.42
.16
.85
T
.03
1.80
.41
.22
.41
,46
.33
2.80
1.47
3.12
5.00
.79
.34
.84
2.55
1.05
.73
.48
.41
.56
1.01
1.49
2.98
1.33
1.49
.96
.64
.47
.45
.37
.34
.49
.89
1.47
2.76
1.31
1.21
.92
.72
.40
.37
.33
.51
.98
1.51
2.70
2.95
1.07
1.08
1.27
1.17
1.03
.46
14.31
16.43
14.85
12.58
8.52
14.07
9.92
8.95
19.48
12.27
11,25
15.05
Glasgow - WPAB, 25 miles south of site (12 year average).
Havre
- Ft.,Assinniboine9 5 miles norjth of study (64 year acerage).
Horris - ^ENE9 % mile east of study (10 year average).
I
-58LITERATURE CITED
Choriki9 Raymond T.$ A. L. Dubbs9 and L. W. Stempke.
1969. Effect of
salt concentration, monuron and diuron on eradication of June grass,
blue grama, clubmoss, and other undesirable shallow rooted species
not important on range establishment.
1969 Mont. Agr. Exp. Station
Report, pp. 35-55.
Dolan, J. J. 1966. Long-term responses of dense clubmoss (Selaginella
densa Rydb.) to range renovation practices in Northern Montana.
M. S. Thesis. Montana State Univ. 83 p.
Duncan, D. B.
11:1-42.
1955.
Multiple range and multiple F tests.
Biometrics
Klages, M. G. and D. E. Ryerson, 1965. Effect of nitrogen and irriga­
tion on yield and botanical composition of Western Montana range.
Agron. Journ. 57:78-81.
Payne, G. F., J. E. Taylor and D. E. Whitmer.
1967. Distribution of
dense clubmqss in Montana. Mont. Agr. Exp. Sta. Cir. 247.
Progress Report, 1965. Clubmoss Research, Mont. Agr. Exp, Sta. and
Bureau of Land Management.
Progress Report, 1966. Clubmoss Research, Mont. Agr. Exp. Sta. and
Bureau of Land Management.
Progress Report, 1967-68. Clubmoss Research, Mont. Agr. Exp. Sta. and
Bureau of Land Management.
Ryerson, D. E., J. E. Taylor, L. 0. Baker, Harold A. Houlton, and D. W.
Stroud.
1969. Clubmoss on Montana Rangelands: Distribution, Con­
trol, Range Relationships. Mont. Agr. Exp. Sta. Bull, (in press).
Stroud, D. W. and L. 0. Baker, 1966.
rangeland to nitrogen and water.
Response of clubmoss infested
WWCC Res. Dept. pp. 16-17.
Wagner, Stephen F. 1966.
Selaginella densa and its chemical control.
M. S. Thesis. Montana State Univ.
Weed Society of America.
1967. Herbicide Handbook.
Press Inc., Geneva, N.Y. 293 p.
W. F. Humphrey
HpfflH
3 '762 10015588 4
f
2378
GtSp
c o p .2
«
»
S tro u d , Don W llns
Cherilcal c o n tr o l o f
cluhmoss
/7