104archive.lib.msu.edu/tic/thesdiss/mcnitt1994c.pdf · studded shoe. why this particular stand of...
TRANSCRIPT
104DISCUSSION
The results section was divided into seven sections, one
section for each of six separate experiments conducted, and
one describing turfgrass stand characterization. The results
of each individual experiment have been summarized in the
results section. This section examines trends or observations
across experiments. Topics to be discussed include the
effects of: species; soil water content; species and soil
water content interaction; verdure wetness; shoe type; shoe
type and soil water content interaction; shoe type and
species interaction; shoe type and traction measurement type
interaction; and turfgrass stand characteristics including
cutting height, verdure, tiller density, and below-ground
biomass on traction values obtained using PENNFOOT.
Species
Kentucky bluegrass and tall fescue had higher traction than
perennial ryegrass and red fescue at peak traction
measurements of 4.4 cm of linear travel in Experiment 2. From
1.3 cm to 2.5 cm of linear travel perennial ryegrass traction
was higher than red fescue, though not significantly higher,
and from 3.2 cm to 5.1 cm of linear travel perennial ryegrass
and red fescue traction values were essentially equal. The
effects of four turfgrass species on traction values in
Experiment 2 were similar to those obtained by Middour
105
(1992), who reported that Kentucky bluegrass and tall fescue
had the highest traction and red fescue the lowest with
perennial ryegrass having intermediate traction values. In
Experiment 2 these species trends held over soil water values
that ranged from an average of 0.18 to 0.34 kg kg-i.
In Experiment 3, traction values due to species differences
were not significantly different. At peak traction
measurements of 40 degrees of rotation, tall fescue had the
highest traction with a value of 29.8 Nm, perennial ryegrass
had the least with a value of 28.6 Nm, and Kentucky bluegrass
was intermediate with a peak traction value of 29.1 Nm. The
magnitude of these differences is small. Middour (1992) found
statistical differences among species when measuring traction
rotationally although perennial ryegrass did not separate
from red fescue. Both perennial ryegrass and red fescue
showed lower rotational traction than Kentucky bluegrass and
tall fescue. While significant differences were not detected
in Experiment 3 the trends due to species were consistent.
In Experiment 4 linear traction values showed a similar
trend, with respect to species, to the results reported by
Middour (1992) and Experiment 2, although Kentucky bluegrass
was not significantly greater than perennial ryegrass in this
instance. In Experiments 2, 3, and 4, species effects on
traction were confounded by other treatments and fewer
106
significant differences were found than Middour (1992)
reported.
Soil Water Content
Soil water content had a varying effect on traction over the
six experiments. In Experiment 1, the average post-irrigation
soil water content of 0.30 kg kg-1 resulted in significantly
higher traction values than the average pre-irrigation soil
water content of 0.21 kg kg-1. In Experiment 2, the traction
values obtained for post-irrigation treatments were not
significantly different from the pre-irrigation treatments
(average soil water contents were 0.33 and 0.18 kg kg-1,
respectively). In experiment 6, the combined experiment
analysis showed that the pre-precipitation treatment produced
higher traction values than the post-precipitation treatment.
Soil water contents averaged '0.17 for the post-precipitation
treatment and 0.13 kg kg-1 for the pre-precipitation
treatment, on this sandy soil. Soil water contents were
measured in Experiments 3, 4, and 5 but were not a treatment.
There was no significant correlation between traction values
and soil water content in Experiment 3. In Experiment 4,
traction values obtained from individual shoes did positively
correlate with soil water contents; however, this result was
confounded by varying water contents among species and is
addressed in the section entitled Species and Soil Water
Content Interaction. Correlation coefficients could not be
107
calculated for Experiment 5 due to experimental design. A
further examination of the effect of soil water content on
traction is discussed in the sections entitled Species and
Soil Water Content Interaction and Shoe Type and Soil Water
Interaction.
Species and Soil Water Content Interaction
No significant statistical interaction between species and
irrigation treatments occurred in Experiment 2. Each species
in Experiment 2 had lower traction values 20 minutes after an
irrigation treatment consisting of 5 cm of water. At 4.4 cm
of linear travel, Kentucky bluegrass traction dropped 43 N
after irrigation was applied, tall fescue dropped 122 N,
perennial ryegrass dropped 120 N, and red fescue dropped 102
N. While the interaction was not statistically significant in
this experiment, Kentucky bluegrass appeared to be less
affected by high soil water conditions than the other
species. Species other than Kentucky bluegrass had a
significant negative correlation with soil water (red fescue,
r = -0.96, perennial ryegrass, r = -0.91, tall fescue, r =-0.93) while Kentucky bluegrass (r = -0.76) did not have a
significant correlation with soil water.
It may be that the rhizomonous growth habit of Kentucky
bluegrass enables it to provide higher traction values under
high soil water condition where soil strength decreases and
108
the morphological characteristics of the grass become more
important. Kentucky bluegrass had significantly more below-
ground biomass than the other species. However, below-ground
biomass alone cannot explain this trend with Kentucky
bluegrass because there was a low correlation between
traction and below-ground biomass. More likely this result is
due to a combination of effects due to both plant and soil
interactions. More work needs to be done on plant
morphological characteristics and their effect on traction
under various soil water contents and soil textural classes.
Verdure Wetness
Experiment 3 was designed to investigate the effects of
moisture on verdure with respect to traction. No significant
traction differences were found between dry and wet verdure
at peak traction values of 40 degrees of rotation; however,
dry verdure had consistently higher traction values under
both loading weights. Due to statistical design, traction
differences due to verdure wetness were tested with an error
term that has only two degrees of freedom. This experiment
should be repeated using a different experimental design. It
can be theorized that dew or gutation water has little effect
on traction until it becomes dislodged and wets the soil
surface. The act of placing a studded foot on the turf can
dislodge the water.
109
Shoe Type
Experiment 4 was designed to compare traction values obtained
using the two shoe types described previously, across species
and cutting heights. The studded shoe had consistently
higher, but not statistically significant, linear traction
values when averaged across species and cutting heights than
did the molded shoe. Traction differences due to shoe types
were tested with an error term that has only 2 degrees of
freedom. The magnitude of difference between peak traction
values obtained with the different shoes was 148 N and is
considered large when compared to other differences that have
been found to be statistically different by this and other
researchers. Significant shoe by species interaction
(discussed later) did show significant shoe differences with
three of the four turfgrass species. It can be assumed that
by using a different statistical design these shoe types
would yield statistically different traction values.
In Experiment 5 there was virtually no difference between the
peak traction values obtained with the molded and studded
shoes when averaged over all loading weights. Although the
difference was not significant, the studded shoe gave
slightly greater traction than the molded shoe at peak
traction values occurring at 4.4 cm of travel for only the
116 kg loading weight. Lighter loading weights of 88 and 59.9
kg showed the molded shoe to 'have higher traction than the
110studded shoe. Why this particular stand of bluegrass yielded
results in which there was little difference between linear
traction values using the different shoes is not clear. The
soil water contents in Experiment 5 averaged approximately
0.24 kg kg-1 for plots on which linear traction was measured
as compared to an average of 0.19 kg kg-1 for Experiment 4.
More soil water in Experiment 5 may have allowed greater
cleat penetration than in Experiment 4; however, cleat
penetration was not determined and differences due to
penetration is only speculation. Kentucky bluegrass tiller
densities were not appreciably different with averages of 168
tillers per plug in Experiment 4 and 167.6 tillers per plug
in Experiment 5. The 'Kentucky bluegrass plots' in Experiment
5 did have a small amount of thatch present, while the
'species plots' had virtually no thatch. The effects of
various levels of thatch have not been investigated; however,
it is possible that thatch would prevent or lessen stud
penetration into the soil. Also it is conceivable that
differences in stand age or degree of wear on a species could
alter its responsiveness to a given shoe type.
In Experiment G.b, rotational traction values obtained with
the molded shoe were significantly higher than those obtained
with the studded shoe at each 10 degree increment of
rotation.
111Shoe Type and Soil Water Content Interaction
Experiment 1 and 2 included similar irrigation treatmentswith the exception that linear traction measurements weremade 20 hours after irrigation was applied in Experiment 1 asopposed to 20 minutes after irrigation was applied inExperiment 2. Experiment 6 was conducted on a sand-modifiedsoil with rotational traction measurements taken before and
immediately after a rainfall.
In Experiment 1, traction values due to irrigation treatmentswere statistically different at 4.4 and 5.1 cm of lineartravel, with the post-irrigation treatment having highertraction values than the pre-irrigation treatment. Althoughnot statistically significant, post-irrigation traction waslower than pre-irrigation traction in Experiment 2 by thesame magnitude difference as in Experiment 1 (114 and 115 Nmrespectively). Experiment 1 and 2 were conducted on differentplot areas, but both were a Hagerstown silt loam soil (seeMaterial and Methods). A loading weight of 102 kg was used inboth Experiment 1 and 2, whereas a 116 kg loading weight wasused in Experiment 6. The molded shoe was used in Experiment1 and 6, whereas the studded shoe was used in Experiment 2.
In practice, the molded shoe is used by athletes on dry soilsand the studded shoe is used when there is more soil waterpresent. The molded shoe has 18 triangular studs (12 rom long)
112
around the perimeter of the sole and 35 smaller studs (9 rom
long) in the center. The studded shoe contains 12 cylindrical
studs, each 12 rom long and 11 rom in diameter. The molded shoe
used in Experiment 1 has more stud surface area than the
studded shoe. Gravimetric soil water values for Experiment 1
averaged 0.21 kg kg-1 pre-irrigation and 0.30 kg kg-1 post-
irrigation. Soil water correlated significantly (r = 0.71)
with traction values when compared across all treatments in
Experiment 1. The increase in traction 20 hours after the
irrigation treatment may be due to increased stud penetration
of the molded shoe. In Experiment 6, significantly lower
traction was obtained on the sandy soil post-precipitation
using the molded shoe. Experiment 6 differed from Experiment
1 in that a heavier loading weight was used to measure
rotational rather than linear traction. Traction values did
not correlate significantly with soil water values in
Experiments 6. A study in which varying water content, shoe
type, soil textural class, and measurement type (rotational
or linear) should be conducted and stud penetration into the
soil should be measured.
In Experiment 3, rotational traction values did not
significantly correlate with soil water content values. Soil
water was not a treatment in Experiment 3 and as a result the
range of soil water values was small, ranging from 0.20 to
0.24 for Kentucky bluegrass, 0.22 to 0.29 for tall fescue and
0.21 to 0.28 for perennial ryegrass.
113
In Experiment 4 there was no significant correlation between
traction on individual species and soil water content.
Individual shoe types did significantly correlate with soil
water content when considered across all treatments. This
result is confounded by varying water contents across
species. Tall fescue and Kentucky bluegrass had average soil
water contents of 0.21 and 0.19 kg kg-i and have been shown to
have higher traction values than perennial ryegrass and red
fescue which had average soil water contents of 0.17 and 0.14
kg kg-i, respectively. It is interesting to note that the
molded shoe was significantly correlated to soil water
content at the 0.01 level (r = 0.88) while the studded shoe
was significant at only the 0.05 level (r = 0.62) and that
traction values obtained with the studded shoe were
significantly correlated with below-ground vegetation (r =0.62) while those obtained with the molded shoe were not (r =0.27). Although soil water contents may have had a greater
effect on the studded shoes' ability to penetrate into the
soil versus the higher stud surface area molded shoe, without
measuring stud penetration this can only be speculated.
Taking all six experiments into consideration it can be said
that although soil water extremes do affect traction, soil
water alone cannot describe varying traction results. In
these studies, it appears that soil water differences not
114
resulting from soil water treatments were confounded with
cutting height and species, which also affect traction.
Conclusions about soil water's effect on traction cannot be
made when data are collected from plots where soil water is
not a treatment or a significant range of soil water levels
does not exist. Since Experiment 2 represents the only
traction measurements taken on plot areas where soil water
was approaching saturation, the possibility that under these
conditions Kentucky bluegrass yielded higher traction values
than other species, possibly due to its rhizomonous
morphology, deserves more study.
The influence of more and varied soil types and soil water
contents on traction needs to be investigated. Also, soil
strength parameters such as the plastic and liquid limits,
should be compared to traction values.
Shoe Type and Species Interactions
A statistically significant shoe by species interaction
occurred in Experiment 4. All linear traction values obtained
on a species with the molded shoe were less than on the same
species with the studded shoe, but this difference was not
significant on the tall fescue stand. At peak traction, the
magnitude of change was much less with tall fescue (29 N)
than with the other species (Kentucky bluegrass - 147 N,
115
perennial ryegrass - 134 N, red fescue - 182 N). The reason
tall fescue maintained higher traction values with the molded
shoe are not apparent. Tall fescue did have the highest soil
water content average when compared to other species, thus
allowing more stud penetration than other species. The strong
bunch-type growth habit of tall fescue may interact with the
molded shoe differently than the way other species interact.
More work is required to explain why species differences
occurred with the molded shoe but not with the studded shoe,
and why tall fescue was unaffected by shoe type.
Shoe Type and Traction Measurement Type Interaction
When measuring traction rotationally in Experiment 5 and 6,
the molded shoe resulted in significantly higher traction at
all incremental degrees of rotation. Thus, under the
conditions of these experiments it can be concluded that when
using PENNFOOT rotationally the molded shoe yields higher
traction values than the studded shoe. When using PENNFOOT
linearly a more mixed picture emerges. In Experiment 4
traction with the studded shoe was consistently higher than
with the molded shoe on three of the four species. In
Experiment 5, however, there was little difference in
traction values obtained with different shoes on Kentucky
bluegrass. Before a standard method of measuring traction on
natural turf is established, more work needs to be done to
establish a standard loading weight and shoe type as well as
116
whether rotational or linear traction should be measured. The
range of traction values obtained when using different shoe
types was greatest when PENNFOOT was used rotationally. When
PENNFOOT was used linearly a greater range of traction values
was obtained from varying turfgrass conditions including
species and cutting heights. Perhaps a standard traction test
method should include more than one loading weight and one
shoe, as well as both rotational and linear measurements.
Vegetative Characteristics
The mowing height treatments in Experiments 2, 3, and 4
affect the vegetative characteristics of the turfgrass plots.
Within the mowing height tolerance for a given species a
lower cutting height results in increased tiller (shoot)
density per unit area, reduction in depth and total quantity
of roots produced, decreased rhizome production, and
decreased transpiration rate (Beard, 1973).
Cutting Height
Differences in traction values due to varying turfgrass
cutting heights were detected when PENNFOOT was measuring
traction linearly in Experiments 1, 2, and 4. Lower cutting
heights resulted in higher traction values regardless of
other treatments. When measuring traction rotationally in
Experiment 3, the same trend of lower cutting heights
117resulting in higher traction values was evident. The
magnitude of the differences was smaller than those found
when measuring traction linearly and differences were
statistically non-significant. These results are consistent
with those of Middour (1992),'who found that traction
differences resulting from varying cutting heights could be
detected when using PENNFOOT linearly but not when it is used
rotationally. The bulk of this work found these conclusions
to be consistent over several years and under a range of
conditions on different plots.
Verdure
In Experiment 1, it was hypothesized that the mass of verdure
between the sole of the shoe and the soil prevents the studs
from penetrating into the soil and thus higher cutting
heights result in lower traction values. Significant
differences in traction values due to varying cutting heights
did occur; however, when verdure was removed just prior to
traction being measured no difference in traction, due to
verdure, was detected. These results suggest that the amount
of verdure, in the range measured, has little effect on
traction.
118
Tiller Density
Numerous researchers (Baker and Canaway, 1991, Baker and
Isaac, 1987, Bell and Holmes, 1988, Canaway, 1983, Holmes and
Bell, 1986, Rogers et al., 1988, Rogers and Waddington, 1989,
Shildrick and Peel, 1984; Winterbottom, 1985) have reported
an increase in traction values as turfgrass cover increases.
In Experiment 1, soil with turfgrass had significantly higher
traction than bare soil.
Shildrick and Peel (1984) attributed increased traction
values to an increase in tiller density. In Experiment 1,
tiller density of tall fescue correlated positively with
linear traction values both before (r = 0.87) and after (r =0.93) irrigation treatments. In Experiments 2 and 3, which
were conducted on the 'species plots', traction values did
not correlate significantly with tiller density under any
condition.
In Experiment 4, individual shoe types negatively correlated
with tiller density when compared across species. This result
is confounded by tiller densities among species. Red fescue
and perennial ryegrass have had consistently higher tiller
densities and lower traction than Kentucky bluegrass and tall
fescue. Shildrick and Peel (1984) describe a method for
comparing tiller size and density to traction. Tiller density
and traction comparisons are most useful when made within a
119
species since morphological differences, such as tiller size,
are not accounted for when comparing tiller counts across
species.
Experiment 6 was conducted on plots in which mowing height
was not a treatment and the range of tiller densities was
small. Traction values did not significantly correlate with
tiller density.
The range of tiller densities between the 'tall fescue' plots
in Experiment 1 and the 'species plots' in Experiments 2, 3,
and 4 was slightly greater in the 'tall fescue' plots. The
lower cutting height plots had the higher tiller densities.
Since results with PENNFOOT have consistently shown lower
cutting height to have the higher traction there should be a
relationship, whether direct or indirect, between tiller
density and traction values in experiments conducted on the
'species plots'. The fact that none existed could be due to
the relative youth and less consistent stand characteristics
of the 'species plots'. In Experiment 1, because of design,
each replication had two tall fescue plots mowed at a
particular height, effectively doubling the number of points
used in the correlation.
120
Below-ground Biomass
No significant correlation existed between traction values
and below-ground vegetation or verdure in Experiments 2 and
3. In Experiment 1, below-ground vegetation correlated (r =-0.88) with linear traction values obtained after irrigation
was applied, and over all treatments (r = -0.66). The higher
cutting heights plots had more below-ground vegetation (Table
30), thus these results are confounded by cutting height
treatments and it becomes difficult to discern the effect of
each. Most likely it is a dynamic relationship in which
below-ground vegetation becomes increasingly important as
soil water content moves towards saturation allowing
increased stud penetration. Below-ground vegetation
correlated positively (r = 0.62) with traction when using the
studded shoe, but had low correlation (r = 0.27) with
traction when using the molded shoe (Table 13). These results
support the supposition that under certain conditions the
lower stud surface area studded shoe will penetrate deeper
into the surface than the molded shoe and allow below-ground
vegetation to affect traction values to a greater degree.
Vegetative characteristics of turfgrass and their
relationship to traction values obtained using PENNFOOT are
inconclusive, with the exception of verdure effects. The
effects of verdure were directly investigated in Experiment 1
and found to have little effect on traction values. In future
121
experiments, vegetative characteristics should be better
controlled so their individual effects can be discerned.
Traction values should be obtained from turfgrass stands
exposed to various levels of wear. Under these conditions a
wider range of vegetative characteristics may occur and any
differences in traction values would be more appropriate when
compared to actual athletic fields.
122
SUMMARY AND CONCLUSIONS
This thesis includes a review of methods developed to measure
traction of natural turfgrass surfaces, a review of the
relevancy of these methods to the actual athlete to shoe to
surface interaction, and a review of turfgrass vegetative and
soil conditions that affect traction.
An apparatus (PENNFOOT) was developed at The Pennsylvania
State University to measure traction. PENNFOOT is a device
that more closely meets the requirements for valid traction
evaluation set forth by Nigg (1990). This device has the
advantage of measuring traction both rotationally and
linearly, accommodating various athletic footwear, and using
loading weights similar to those exerted by athletes. The
device is portable and measurements can be made in situ.
In order to more fully test PENNFOOT over a wider range of
conditions and to evaluate the turfgrass and soil
characteristics that affect traction values obtained with
this device, more research was required.
PENNFOOT was used in six experiments to determine the effects
of various factors on traction. These factors included
turfgrass species (Kentucky bluegrass, tall fescue, perennial
ryegrass, red fescue), cutting heights (ranging from 2.3 to
7.6 cm), verdure (present or removed), soil water contents
123
(averaging from 0.20 to 0.30 kg kg-1 and 0.18 to 0.34 kg kg-1
on silt loam soils and 0.13 to 0.17 kg kg-1 on a sandy loam
soil), loading weights (ranging from 47.6 to 116 kg), and
shoe types (molded and studded sole) .
Species differences were detected with the molded shoe but
not the studded shoe. In general, traction on species
followed the order tall fescue ~ Kentucky bluegrass >
perennial ryegrass ~ red fescue. Shoe type did not
significantly affect traction on tall fescue, but with the
other species traction was greater with the studded shoe.
Linear traction was usually higher with lower cutting
heights. Rotational traction was not significantly influenced
by cutting height, but a trend for greater traction with
lower cutting height was present. Removal of verdure on tall
fescue maintained at three cutting heights did not influence
traction. Soil water content affected traction, but the
effect was not consistent across experiments, apparently due
to differences such as range of soil water contents, and type
of traction measurements used. Traction increased with
increasing loading weight.
Although traction on natural surfaces was affected by turf
species, cutting height, soil water content, and shoe type,
it is difficult to generalize about these effects due to
interactions among these factors and the influence of other
factors not measured.
124
This research has raised questions that should be addressed
in future research. For example, why did a shoe by species
interaction exist, how does varying soil water content
interact with soil texture to affect traction, and what
relationship exists among compaction, turfgrass cover, and
traction? The depth of stud penetration into the turf could
explain some differences in traction, but it was not
measured. This factor should be taken into consideration in
future work.
Under the conditions of these experiments, it appears that
recording peak values, rather than the entire curve, would be
sufficient to assess the effects of the various treatments.
In this and previous experiments the peak traction values
generally occurred at 30 or 40 degrees rotation and at 3.8 or
4.4 cm of linear travel. However, in future work on areas
having somewhat different surface characteristics, the
incremental values should be observed to determine
similarities or differences in values throughout the entire
range of motion.
A much more extensive data base is needed to provide
guidelines for maximum playability and to predict the
influence of management practices on traction. Within this
data base an evaluation of human performance as it relates to
traction measurements should be included.
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Turf Res. Inst. 65:80-90.Rogers III, J.N., and D.V. Waddington. 1990. Effects of
management practices on impact absorption and shearresistance in natural turf. p. 136-146. In R.C. Schmidtet al. (ed.) Natural and artificial playing fields:characteristics and safety features. ASTM STP 1073.
ASTM, philadelphia, PA,Rogers, J.M., D.V. Waddington and J.C. Harper. 1988.
Relationships between athletic field hardness andtraction, vegetation, soil properties, and maintenance
practices. Progress Report 393. The Penna. St. Univ.,College of Agri., Exp. Station., Univ. Park, PA. 15 pp.
Shildrick, J.P. and C.H. Peel. 1984. Shoot numbers, biomassand shear strength in smooth-stalked meadow-grass (poa
Pratensis). J. Sports Turf Res. Inst .. 60:66-72.
130Stanitske, C.L,. McMaster, J.H. and Ferguson, R.J.
(1974) .Synthetic turf and grass - a comparative study.J. Sports Medicine 2, I, 22-26.
Torg, J.S. and T.C. Quedenfeld. 1973. Knee and ankle injuriestraced to shoes and cleats. Physician Sports Med. 1:39-
43.
Torg, J.S. and T.C. Quendenfeld and S. Landau .. 1974. Theshoe-surface interface and its relationship to footballknee injuries. J. Sports Med. 2:261-269.
Waddington, D.V., T.L. Zimmerman, G.J. Shoop, L.T. Kardos andJ.M. Duich. 1974. Soil modification for turfgrassareas. I. Physical properties of physically amendedsoils. Pennsylvania Agri. Exp. Stn. Prog. Rep. 337.
Winterbottom, W. 1985. Artificial grass surfaces forAssociation Football, Sports Council, London, 127 pp.
Zebarth, B.J. and R.W. Sheard. 1985. Impact and shearresistance of turfgrass racing surfaces forthoroughbreds. Am. J. Vet. Res. 46(4) :778-784.
APPENDIX
ADDITIONAL MATERIALS
131
...;..,~:....
:;(~{)~~${~~r.iii::'
Fig. 19. PENNFOOT traction measuring device.
132
133
Fig. 20. Studded and Molded shoes used with PENNFOOTtraction measuring device.
Table 26. Mean traction values for the designated variable in Experiment 1.
Variable 1.3 1.9 2.5ernof travel
3.2 3.8 4.4 5.1
Treatment2.3 ern2.3 em*5.1 ern5.1 em*7.6 ern7.6 em*
Bare soillsd (0.05)
----------------------------------- N ------------------------------------1022 1219 1382 1496 1601 1609 16151027 1222 1374 1478 1569 1583 15891004 1202 1324 1417 1511 1537 15431030 1214 1345 1435 1522 1516 15131016 1176 1292 1365 1435 1458 14671007 1199 1342 1412 1487 1493 1490978 1065 1132 1131 1118 1100 1091NS 63 55 66 65 76 72
--------------------------------------------------------------------------------------Soil water
-------------------------------- N ---------------------------------
pre- 1007 1180 1306 1369 1428 1424 1415irrigation
post- 1017 1191 1321 1412 1498 1518 1530irrigationlsd (0.05) NS NS NS NS NS 62 35
*verdure removed
Table 27. Gravimetric water content for each pre- and post-irrigationtreatment plot in Experiment 1.
Treatment----- Replications -----
Cutting height Verdure I II III Average
cm ------- kg H20/ kg dry soil --------
Pre-irriaation2.3 present .21 .26 .27 .255.1 present .15 .24 .27 .227.6 present .18 .22 .23 .212.3 absent .24 .29 .28 .275.1 absent .21 .23 .24 .237.6 absent .18 .19 .21 .19
Bare soil .10 .10 .10 .10
Post-irriaation2.3 present .30 .34 .32 .325.1 present .28 .34 .35 .327.6 present .30 .33 .36 .332.3 absent .32 .36 .36 .355.1 absent .28 .34 .34 .327.6 absent .32 .28 .33 .31
Bare soil .17 .20 .14 .17
-IN\.1'1
Table 28. Mean linear traction values for treatment x soil water for Experiment 1.
----------------------- em of travel -----------------------Cutting Verdure Irrigation 1.3 1.9 2.5 3.2 3.8 4.4 5.1height
(em) ---------------------------- N -----------------------------2.3 present pre 1019 1222 1374 1484 1566 1560 15482.3 absent pre 1036 1217 1385 1461 1537 1531 15312.3 present post 1024 1217 1391 1508 1636 1659 16822.3 absent post 1019 1228 1362 1496 1601 1636 16475.1 present pre 984 1176 1298 1368 1455 1478 14615.1 absent pre 1013 1199 1327 1403 1484 1473 14495.1' present post 1024 1228 1350 1467 1566 1595 16245.1 absent post 1048 1228 1362 1467 1560 1560 15777.6 present pre 1019 1176 1281 1339 1391 1409 14147.6 absent pre 1009 1199 1350 1409 1461 1438 14207.6 present post 1013 1176 1304 1391 1478 1508 15197.6 absent post 995 1199 1333 1414 1513 1548 1560
Bare soil pre 960 1071 1123 1118 1100 1048 1083Bare soil post 995 1059 1141 1144 1135 1118 1100lsd (0.05) NS NS NS NS NS NS NS
137
Table 29. Mean weight of verdure, below-ground vegetation,and tiller counts per sample plug for eachtreatment plot in Experiment 1.
Treatment Replications --Cutting height Verdure I II III Average
cm ------ g/81 cm2 plug ------
Verdure
2.3 present 2.5 1.9 2.0 2.15.1 present 3.3 3.3 2.4 3.07.6 present 3.7 3.1 2.8 3.22.3 absent 0.0 0.0 0.0 0.05.1 absent 0.0 0.0 0.0 0.07.6 absent 0.0 0.0 0.0 0.0
Bare soil 0.0 0.0 0.0 0.0
Below-aroundveaetation
------ g/81 cm2 plug ------
2.3 present 3.2 4.1 5.1 4.15.1 present 3.7 4.4 4.7 4.37.6 present 4.8 4.2 5.5 4.82.3 absent 3.9 4.2 4.0 4.05.1 absent 4.1 4.9 4.2 4.47.6 absent 3.8 5.7 5.6 5.0
Bare soil 0 0 0 0.0
Table 30. Mean traction values for the designated variable obtainedfrom Experiment 2.
1.3 1.9 2.5 em of travel ----------------------3.2 3.8 4.4 5.1
SpeciesKy. bluegrassTall fescuePro ryegrassRed fescuelsd .(0.05)
---------------------------- N1277 1410 1486 15481237 1367 1450 15171223 1336 1415 14461210 1312 1377 143529 71 71 86
1604157614661478
90
162815991478148492
1622160314821477101
-------------------------------------------------------------------------------Cutting Height3.8 em5.1 em6.4 em
lsd (0.05)
124712291234NS
13761350134331
14551425141531
15061480147428
15531525151533
157315411528
36
15681543152723-------------------------------------------------------------------------------Irrigation
pre- 1297 1403 1483 1543 1588 1595 1584irrigation
post- 1176 1309 1381 1430 1474 1499 1508irrigationlsd (0.05) NS NS NS NS NS NS NS
Table 31. Mean gravimetric soil water values before and after irrigation treatmentfor blocks, species, and cutting heights for Experiment 2.
Blocks123
lsd (0.05)
SpeciesKy. bluegrassTall fescuePro ryegrassRed fescueIsd (0.05)
Cutting height3.8 cm5.1 cm6.4 cm
Isd (0.05)
Pre-irrigation
0.170.180.18. NS
0.190.210.170.14
0.016
0.170.180.18NS
Soil water
kg / kgPost-irrigation
0.310.370.33
0.019
0.340.360.330.31
0.022
0.340.330.33NS
Table 32. Mean traction values for the species x irrigation treatment obtainedfrom Experiment 2.
1.3 1.9 2.5cm of travel --------------------
3.2 3.8 4.4 5.1
SpeciesKy. bluegrassKy. bluegrassTall fescueTall fescuePro ryegrassPro ryegrassRed fescueRed fescueIsd (0.05)
Irrigationprepostprepostprepostprepost
------------------------- N -------------------------1339 1467 1541 1597 1643 1650 16331215 1352 1432 1500 1563 1607 16111283 1405 1495 1576 1640 1660 16471191 1329 1405 .1458 1513 1538 15581298 1380 1447 1510 1535 1538 15271122 1244 1306 1360 1397 1418 14261269 1362 1450 1492 1535 1535 15281178 1310 1381 1401 1422 1433 1436NS NS NS NS NS NS NS
....~o
Table 33. Mean weight of below-ground vegetation per sample plug(81 cm2 by 2 cm depth) for each species x cutting heightplot in Experiments 2, 3, and 4.
----- Replications -----Species Cutting I II III Average
Heightcm -------------- g/plug -------------
Red fescue 3.8 5.0 5.4 5.2 5.2Red fescue 5.1 5.2 5.3 5.3 5.3Red fescue 6.4 5.2 5.7 5.0 5.3
Ky. bluegrq.ss 3.8 7.5 8.3 8.9 8.2Ky. bluegrass 5.1 8.0 7.9 7.8 7.9Ky. bluegrass 6.4 7.3 8.5 8.5 8.1
Pro ryegrass 3.8 3.7 3.1 3.8 3.5Pro ryegrass 5.1 4.3 2.8 3.7 3.6Pro ryegrass 6.4 3.5 3.8 3.3 3.5
Tall fescue 3.8 4.9 5.4 4.6 5.0Tall fescue 5.1 5.7 5.3 4.8 5.3Tall fescue 6.4 6.2 7.0 5.4 6.2
Isd (0.05) 1.23
....~....
Table 34. Mean traction values for cutting height x irrigationfor Experiment 2.
Cuttingheight
3.8 em5.1 em6.4 em3.8 em5.1 em6.4 em
Isd (0.05)
Irrigation
prepreprepostpostpost
---------------- em of travel ----------------1.3 1.9 2.5 3.2 3.8 4.4 5.1
--------------------- N -----------------------1316 1426 1509 1564 1612 1623 16091288 1397 1480 1538 1588 1596 15891288 1387 1460 1528 1564 1567 15541179 1326 1401 1448 1494 1524 15271170 1302 1371 1422 1462 1486 14961180 1298 1371 1420 1465 1489 1500
NS NS NS NS NS NS NS
Table 35. Mean traction values for species x cutting height obtainedfrom Experiment 2.
1.3 1.9 2.5 cm of travel --------------------3.2 3.8 4.4 5.1
SpeciesKy. bluegrassKy. bluegrassKy. bluegrassTall fescue
.Tall fescueTall fescuePro ryegrassPro ryegrassPro ryegrassRed fescueRed fescueRed fescuelsd (0.05)
CuttingHeight3.8 em5.1 cm6.4 em3.8 em5.1 em6.4 em3.8 em5.1 em6.4 em3.8 cm5.1 cm6.4 cm
NS
------------------------- N -------------------------1292 1426 1510 1577 1636 1653 16411266 1397 1478 1537 1593 1621 16251272 1405 1470 1531 1583 1609 16011234 1380 1458 1526 1593 1625 16251231 136& 1461 1516 1586 1609 16091246 1354 1429 1510 1551 1563 15741225 1345 1415 1464 1496 1507 14931196 1295 1353 1424 1450 1461 14641208 1295 1362 1418 1453 1467 14721237 1353 1438 1458 1491 1507 15131222 1339 1408 1443 1472 1472 14721211 1316 1400 1438 1471 1472 1461NS NS NS NS NS NS NS
Table 36. Mean weiqht of verdure per sample plug (81 em2) for eachspecies x cuttinq heiqht plot in Experiments 2, 3, and 4.
Replications -----Species Cuttinq T II III Averaqe...
heiQhtem ------------- q/plug--------------
Red fescue 3.8 2.6 2.4 2.3 2.4Red fescue 5.1 3.t 3.2 2.9 3.2Red fescue 6.4 4.4 3.4 3.3 3.7
Ky. bluegrass 3.8 2.9 2.9 2.6 2.8Ky. bluegrass S.l 3.3 3.5 3.2 3.3Ky. bluegrass 6.4 4.0 3.8 3.8 3.9
Pro ryegrass 3.8 2.1 2.5 3.0 2.7Pro ryegrass 5.1 3.4 2.5 3.0 2.9Pro ryegrass 6.4 3.6 3.0 3.2 3.3
Tall fescue 3.8 2.8 3.0 2.7 2.8Tall fescue S.l 3.4 2.9 2.9 3.1Tall fescue 6.4 3.6 3.7 3.0 3.4
....
Table 37. Mean number of tillers per plug (81 cm2) for eachspecies x cutting height plot in Experiments 2, 3, and 4.
----- Replications ----Species Cutting I II III Average
heightcm ------------ no./plug ------------
Red fescue 3.8 217 153 226 199Red fescue 5.1 257 217 213 229Red fescue 6.4 183 205 186 191
Ky. bluegrass 3.8 193 183 lS9 188Ky. bluegrass 5.1 178 162 175 171Ky. bluegrass 6.4 144 149 145 146
Pro ryegrass 3.8 235 243 229 236Pro ryegrass 5.1 248 187 198 211Pro ryegrass 6.4 165 164 163 164
Tall fescue 3.8 111 148 123 127Tall fescue 5.1 120 99 103 107Tall fescue 6.4 92 100 91 94
-~\JI
Table 38. Mean traction values for the designated variablesobtained from rotational measurements in Experiment 3using a 102 kg. loading weight.
Variable
Species
-------- degrees of rotation ---------10 20 30 40
----------------- Nm -----------------Tall fescue
Ky. bluegrassPro ryegrass
lsd (0.05)
22.722.222.0NS
26.726.125.8NS
29.428.728.4NS
29.829.128.6NS
--------------------------------------------------------------Cutting height
2.3 em 22.6 26.5 29.2 29.45.1 em 22.1 26.0 28.7 29.17.6 em 22.2 26.0 28.6 29.0
lsd (0.05) NS NS NS NS
--------------------------------------------------------------Verdure wetness
Dry verdureWet verdurelsd (0.05)
22.522.1NS
26.326.1NS
29.428.2NS
29.928.5NS
Table 39. Mean traction values for the designated variablesobtained from rotational measurements in Experiment 3using a 47.6 kg loading weight.
Variable -------- degrees of rotation ---------10 20 30 40
----------------- Nm -----------------Species
Tall fescueKy. bluegrassPro ryegrass
lsd (0.05)
12.512.211.8NS
14.714.313.7NS
16.015.514.9NS
16.115.715.3NS
Cutting height
2.3 cm 12.2 14.2 15.3 15.65.1 cm 12.1 14.3 15.6 15.87.6 cm 12.3 14.2 15.4 15.7
lsd (0.05) NS NS NS NS
Verdure wetness
Dry verdureWet verdurelsd (0.05)
12.312.1NS
14.514.0NS
15.815.1NS
16.215.3NS
Table 40. Mean rotational traction values for grass species x verdurewetness in Experiment 3 using a loading weight of 102 kg.
Verdure ------ degrees of rotation-------Species wetness 10 20 30 40
----------------.Nm ---------------Tall fescue dry 22.8 26.7 29.9 30.3Tall fescue wet 22.7 26.6 28.9 29.3Ky. bluegrass dry 22.0 26.0 29.2 29.7Ky. bluegrass wet 22.4 26.1 28.3 28.6Pro ryegrass dry 22.6 26.1 29.3 29.6Pro ryegrass wet 21.3 25.5 27.6 27.6lsd (0.05) 1.4 NS NS NS
Table 41. Mean rotational traction values for grass species x Verdurewetness in Experiment 3 using a loading weight of 47.6 kg.
Verdure ------ degrees of rotation-------Species wetness 10 20 30 40
---------------- Nm ---------------Tall fescue dry 12.4 14.8 16.2 16.4Tall fescue wet 12.6 14.6 15.7 15.8Ky. bluegrass dry 12.4 14.7 16.0 16.3Ky. bluegrass wet 12.1 13.9 15.0 15.1Pro ryegrass dry 11.9 14.0 15.2 15.8Pro ryegrass wet 11. 8 13.4 14.6 14.9
lsd (0.05) NS NS NS NS
Table 42. Mean rotational traction values for grass species x cuttingheight in Experiment 3 using a loading weight of 102 kg.
Cutting - -- --- degrees of rotation-------Species height 10 20 30 40
--------------- Nm ----------------Ky. bluegrass 2.3 em 22.2 26.2 28.7 29.0Ky. bluegrass 5.1 em 22.0 25.9 28.8 29.4Ky. bluegrass 7.6 em 22.3 26.1 28.6 28.9Pro ryegrass 2.3 em 22.2 26.1 28.8 28.9Pro ryegrass 5.1 em 21.6 25.2 27.9 28.1Pro ryegrass 7.6 em 22.1 26.1 28.6 28.9Tall fescue 2.3 em 23.2 27.2 30.1 30.4Tall fescue 5.1 em 22.7 26.8 29.5 29.8Tall fescue 7.6 em 22.3 26.0 28.6 29.3lsd (0.05) NS NS NS NS NS
....VIo
Table 43. Mean rotational traction values for grass species x cuttingheight in Experiment 3 using a loading weight of 47.6 kg.
Cutting ------ degrees of rotation-------Species height 10 20 30 40
--------------- Nm ----------------Ky. bluegrass 2.3 em 12.1 14.3 15.3 15.6Ky. bluegrass 5.1 em 12.2 14.3 15.7 15.9Ky. bluegrass 7.6 em 12.4 14.3 15.5 15~6Pro ryegrass 2.3 em 11.9 13.5 14.6 15.1Pro ryegrass 5.1 em 11.7 13.7 15.1 15.4Pro ryegrass 7.6 em 12.0 14.0 15.0 15.5Tall fescue 2.3 em 12.6 14.8 16.0 16.2Tall fescue 5.1 em 12.5 14.9 16.0 16.2Tall fescue 7.6 em 12.4 14.4 15.9 15.9lsd (0.05) NS NS NS NS NS
.....VI.....
Table 44. Mean rotational traction values for cutting height x verdurewetness in Experiment 3 using a loading weight of 102 kg.
Cutting Verdure ------ degrees of rotation-------height wetness 10 20 30 40
---------------- Nm ---------------2.3 em dry 22.6 26.7 30.0 30.22.3 em wet 22.5 26.3 28.4 28.65.1 em dry 22.2 25.9 29.2 29.75.1 em wet 22.0 26.0 28.3 28.57.6 em dry 22.5 26.2 29.1 29.77.6 em wet 21.9 25.9 28.1 28.4
lsd (0.05) NS NS NS NS
~VIN
Table 45. Mean rotational traction values for cutting height x verdurewetness in Experiment 3 using a loading weight of 47.6 kg.
Cutting Verdure ------ degrees of rotation-------height wetness 10 20 30 40
---------------- Nm ---------------2.3 em dry 12.1 14.5 15.7 16.02.3 em wet 12.3 14.0 15.0 15.25.1 em dry 12.3 14.5 15.8 16.25.1 cm wet 12.0 14.2 15.3 15.47.6 em dry 12.4 14.7 15.9 16.27.6 cm wet 12.1 13.8 15.0 15.1
lsd (0.05) NS NS NS NS
Table 46. Mean rotational traction values for species x cutting height x verdurewetness in Experiment 3 using a loading weight of 102 kg.
Species CUtting Verdure ------ degrees of rotation-------height wetness 10 20 30 40
--------------- Nm ----------------Tall fescue 2.3 cm dry 22.5 26.3 28.4 28.6Tall fescue 2.3 em wet 22.2 25.9 29.2 29.7Tall fescue 5.1 em dry 22.0 26.0 28.3 28.5Tall fescue 5.1 em wet 22.5 26.2 29.1 29.7-Tall fescue 7.6 em dry 21.9 25.9 28.1 28.4Tall fescue 7.6 em wet 22.2 26.2 28.3 29.0Ky. bluegrass 2.3 em dry 21.9 26.1 29.4 29.6Ky. bluegrass 2.3 em wet 22.5 26.3 28.1 28.4Ky. bluegrass 5.1 em dry 21.6 25.5 28.8 29.6Ky. bluegrass 5.1 em wet 22.4 26.4 28.9 29.2Ky. bluegrass 7.6 em dry 22.4 26.5 29.4 29.8Ky. bluegrass 7.6 em wet 22.2 25.6 27.8 28.1Pr. ryegrass 2.3 em dry 23.0 26.9 30.3 30.5Pr. ryegrass 2.3 em wet 21.5 25.2 27.2 27.2Pr. ryegrass 5.1 em dry 22.2 25.2 28.4 28.7Pro ryegrass 5.1 em wet 21.1 25.2 27.4 27.5Pr. ryegrass 7.6 em dry 22.8 26.2 29.1 29.7Pr. ryegrass 7.6 em wet 21.3 25.9 28.1 28.1
lsd (0.05) NS NS NS NS
-U\$:-
Table 47. Mean rotational traction values for species x cutting height x verdurewetness in Experiment 3 using a loading weight of 47.6 kg.
Species Cutting Verdure ------ degrees of rotation-------height wetness 10 20 30 40
--------------- Nm ----------------Tall fescue 2.3 cm dry 12.3 14.7 16.0 16.2Tall fescue 2.3 cm wet 12.9 14.9 16.0 16.2Tall fescue 5.1 cm dry 12.1 14.5 15.9 16.3Tall fescue 5.1 cm wet 12.9 15.2 16.0 16.2Tall fescue 7.6 cm dry 12.9 15.2 16.7 16.7Tall fescue 7.6 em wet 12.0 13.7 15.0 15.1Ky. bluegrass 2.3 em dry 11. 9 14.7 16.2 16.5Ky. bluegrass 2.3 em wet 12.3 13.9 14.5 14.6Ky. bluegrass 5.1 em dry 12.7 14.9 16.2 16.4Ky. bluegrass 5.1 em wet 11.7 13.8 15.2 15.5Ky. bluegrass 7.6 cm dry 12.5 14.6 15.7 15.9Ky. bluegrass 7.6 em wet 12.3 13.9 15.3 15.3Pro ryegrass 2.3 em dry 12.0 13.9 14.9 15.4Pro ryegrass 2.3 em wet 11.7 13.1 14.4 14.7Pro ryegrass 5.1 em dry 11.9 14.0 15.4 16.0Pro ryegrass 5.1 em wet 11.6 13.4 14.7 14.9Pro ryegrass 7.6 em dry 11. 9 14.2 15.2 16.0Pro ryegrass 7.6 em wet 12.0 13.8 14.7 15.0
lsd (O.05) NS 1.15 NS NS
-VIVI
Table 48. Mean soil water for species x cutting height subplots in Experiment 3.
----- ReplicationsSpecies CUtting I II III Average
heightcm grams H20 per grams of dry soil --
Ky. bluegrass 3.8 0.20 0.24 0.23 0.22Ky. bluegrass 5.1 0.21 0.23 0.24 0.23Ky. bluegrass 6.4 0.20 0.24 0.23 0.22
Pro ryegrass 3.8 0.28 0.26 0.27 0.27Pro ry~rass 5.1 0.27 0.27 0.21 0.25Pro ryegrass 6.4 0.21 0.29 0.23 0.24
Tall fescue 3.8 0.24 0.26 0.28 0.26Tall fescue 5.1 0.22 0.25 0.29 0.25Tall fescue 6.4 0.24 0.27 0.28 0.26
Table 49. Mean traction values for the designated variable obtainedfrom Experiment 4.
Variable 1.3 1.9 2.5em of travel
3.2 3.8 4.4 5.1
SpeciesTall fescue
Ky. bluegrassPr. ryegrassRed fescuel..d CO.05)
---------------------------- N ----------------------------1237 1389 1506 1576 1636 1644 16381256 1389 1464 1522 1573 1576 15621193 1304 1384 1446 1472 1472 14511185 1277 1340 1377 1400 1394 138067 79 107 137 147 147 140
CUtting height3.8 em 1238 1369 1458 1513 1551 1551 15295.1 em 1209 1332 1416 1481 1522 1524 15166.4 em 1206 1319 1386 1446 1487 1489 1478
lsd CO.05) NS NS 54 47 42 54 NS
Shoe type
Studded shoe 1297 1403 1485 1543 1588 1595 1584Molded shoe 1138 1276 1355 1417 1452 1447 1431lsd CO.05) NS NS NS NS NS NS NS
Table 50. Mean traction values for species x shoe type obtainedfrom Experiment 4.
------------------- em of travel1.3 1.9 2.5 3.2 3.8 4.4 5.1
SpeciesTall fescueTall fescueKy. bluegrassKy. bluegrassPr. ryegrassPr. ryegrassRed fescueRed fescue
lsd (0.05)
Shoe typestuddedmoldedstuddedmoldedstuddedmoldedstuddedmolded
-------------------------N -------------------------1283 1405 1504 1576 1640 1659 16471191 1374 1480 1577 1632 1630 16281339 1467 1541 1597 1643 1649 16341174 1312 1387 1447 1502 1502 14901298 1380 1447 1510 1535 1539 15271088 1228 1321 1381 1409 1405 13761269 1362 1449 1492 1535 1535 15291100 1191 1230 1261 1265 1253 1230NS 114 118 113 117 139 149
Table 51. Mean traction values for species x cutting height obtainedfrom Experiment 4.
------------------ em of travel1.3 1.9 2.5 3.2 3.8 4.4 5.1
SpeciesKy. bluegrassKy. bluegrassKy. bluegrassTall fescueTall fescueTall fescuePro ryegrassPro ryegrassPro ryegrassRed fescueRed fescueRed fescueIsd (0.05)
Cuttingheight3.8 em5.1 em6.4 em3.8 em5.1 em6.4 em3.8 em5.1 em6.4 em3.8 em5.1 em6.4 em
NS
------------------------- N -------------------------1272 1417 1499 1563 1618 1615 15921260 1385 1476 1531 1580 1583 15751237 1365 1417 1473 1519 1528 15191246 1417 1526 1598 1639 1650 1:6361228 1382 1490 1583 1659 1665 16621237 1368 1461 1548 1609 1618 16151222 1336 1435 1493 1522 1522 14811167 1289 1362 1429 1446 1449 14411190 1286 1356 1414 1446 1444 14321211 1304 1374 1400 1423 1417 14091182 1272 1336 1382 1403 1400 13851161 1254 1310 1348 1374 1365 1345NS NS NS NS NS NS NS
-V1\0
Table 52. Mean traction values for cutting height x shoe typefor Experiment 4.
Cuttingheight
3.8 em5.1 em6.4 em3.8 em5.1 em6.4 em
lsd (0.05)
Shoe type
moldedmoldedmoldedstuddedstuddedstudded
---------------- em of travel ----------------1.3 1.9 2.5 3.2 3.8 4.4 5.1
---------------------- N ----------------------1160 1311 1400 1462 1489 1480 14491131 1267 1352 1425 1457 1452 14421125 1250 1313 1364 1410 1410 14011316 1426 1517 1564 1612 1623 16091288 1397 1480 1538 1588 1596 15891288 1387 1460 1528 1564 1567 1554NS NS NS NS NS NS NS
-0-o
Table 53. Mean rotational traction values for species x cutting height x shoe typefor Experiment 4.
Species Shoe CUtting ----------------- cm of travel ------------------type height 1.3 1.9 2.5 3.2 3.8 4.4 5.1
----------------------- N ------------------------Tall fescue molded 2.3 em 1199 1397 1513 1607 1624 1612 1595Tall fescue molded 5.1 em 1182 1362 1467 1589 1653 1647 1653Tall fescue molded 7.6 em 1193 1362 1461 1537 1618 1630 1636Tall fescue studded 2.3 em 1292 1438 1538 1589 1653 1688 1676Tall fescue studded 5.1 cm 1275 1403 1513 1577 1665 1682 1671Tall fescue studded 7.6 em 1281 1375 1461 1560 1601 1607 1595Ky. bluegr~ss molded 2.3 em 1187 1345 1432 1496 1560 1554 1537Ky. bluegrass molded 5.1 em 1187 1321 1409 1473 1513 1502 1490Ky. bluegrass molded 7.6 em 1147 1269 1321 1374 1432 1449 1444Ky. bluegrass studded 2.3 em 1356 1490 1566 1630 1676 1676 1647Ky. bluegrass studded 5.1 em 1333 1449 1543 1589 1647 1665 1659Ky. bluegrass studded 7.6 em 1327 1461 1513 1572 1607 1607 1595Pro ryegrass molded 2.3 em 1135 1286 1397 1467 1496 1490 1432Pro ryegrass molded 5.1 em 1054 1199 1286 1339 1356 1362 1350Pr. ryegrass molded 7.6 em 1077 1199 1281 1339 1374 1362 1345Pro ryegrass studded 2.3 em 1310 1385 1473 1519 1548 1554 1531Pro ryegrass studded 5.1 em 1281 1380 1438 1519 1537 1537 1531Pro ryegrass studded 7.6 em 1304 1374 1432 1490 1519 1525 1519Red fescue molded 2.3 em 1118 1217 1257 1281 1275 1263 1234Red fescue molded 5.1 em 1100 1187 1246 1298 1304 1298 1275Red fescue molded 7.6 em 1083 1170 1187 1205 1217 1199 1182Red fescue studded 2.3 em 1304 1391 1490 1519 1572 1572 1583Red fescue studded 5.1 em 1263 1356 1426 1467 1502 1502 1496Red fescue studded 7.6 em 1240 1339 1432 1490 1531 1531 1508
1sd (0.05) NS NS NS NS NS NS NS~C7\~
Table 54. Mean traction values for blocks across species, cutting height, and shoetypes for Experiment 4.
1.3 1.9 2.5em of travel
3.2 3.8 4.4 5.1
Block123
lsd(0.05)
---------------------------------N --------------------------------1216 1346 1428 1489 1530 1533 15251265 1373 1446 1498 1521 1518 15041172 1300 1386 1453 1508 1513 1494
64 NS NS NS NS NS NS
Table 55. Mean soil water content for species x cutting height subplots in Experiment 4.
----- Replications ----Species Cutting I II III Average
heightcm ------------ kg / kg -------------
Red fescue 3.8 0.08 0.14 0.09 0.10Red fescue 5.1 0.14 0.16 0.16 0.15Red fescue 6.4 0.17 0.16 0.17 0.17
Ky. bluegrass 3.8 0.18 0.20 0.22 0.20Ky. bluegrass 5.1 0.20 0.16 Q.18 0.18Ky. bluegrass 6.4 0.18 0.17 0.21 0.19
Pro ryegrass 3.8 0.18 0.16 0.20 0.18Pro ryegrass 5.1 0.17 0.18 0.18 0.18Pro ryegrass 6.4 0.14 0.17 0.17 0.16
Tall fescue 3.8 0.20 0.20 0.24 0.21Tall fescue 5.1 0.18 0.22 0.23 0.21Tall fescue 6.4 0.18 0.20 0.21 0.20
Table 56. Mean traction values for the designated variable obtainedfrom linear measurements in Experiment 5.
---------------------------- N ----------------------------Loading weight
116 kg88 kg
59.9 kglsd (0.05)
Shoe type
Molded shoeStudded shoelsd (0.05)
1.3
1222106886729
10241081
23
1.9
14141179~4937
11701191NS
2.5
1519124099832
12481257NS
cm of travel3.2
160713481051
45
13311339NS
3.8
17201394107155
13991391NS
4.4
1752141710~850
14161409NS
5.1
175214171068
50
14161409NS
Table 57. Mean traction values for the designated variablesobtained from rotational measurements in Experiment 5.
Variable
Loading weight
-------- degrees of rotation ---------10 20 30 40
----------------- Nm -----------------116 kg88 kg
59.9 ~glsd (0.05)
2220151
2825192
3328212
3530222
--------------------------------------------------------------Shoe type
Molded shoeStudded shoe
lsd (0.05)
20181
26221
30252
32262
Table 58. Mean traction values for the loading weight x shoe type interactionobtained from Experiment 5.
Loadingweight
Shoetype
-------------------cm of travel1.3 1.9 2.5 3.2 3.8 4.4 5.1
59.9 kg88 kg116 kg59.9 kg88 kg116 kg
lsd (0.05)
MoldedMoldedMoldedStuddedStuddedStudded
------------------------- N -------------------------856 949 1001 1071 1088 1083 10831036 1164 1228 1333 1391 1420 .14201182 1397 1513 1589 1717 1746 1746879 949 995 1030 1054 1054 10541100 1193 1251 1362 1397 1414 14141263 1432 1525 1624 1723 1758 1758NS NS NS NS NS NS NS
Table 59. Mean rotational traction values for loading weight xshoe type in Experiment 5.
Loading Shoe ------ degrees of rotation-------weight type 10 20 30 40
--------------- Nm ----------------59.9 kg Molded 16 20 23 2488 kg Molded 22 28 31 33116 kg Molded 23 31 3.6 3959.9 kg Studded 15 17 19 2088 kg Studded 18 23 25 27116 kg Studded 22 26 30 31
lsd (0.05) NS NS NS NS
Table 60. Plot characteristics for blocks in Experiment 5 for bothrotational and linear measurements.
BelowMeasurement ground Tiller Soil
type Block vegetation Verdure density water
---- g/plug -no/plug- - kg/kg -Linear 1 9.7 2.8 162 0.23Linear 2 11.7 3.2 166 0.25Linear 3 10.4 3.5 175 0.25
Rotational 1 10.5 3.1 176 0.23Rotational 2 8.3 3.7 163 0.24Rotational 3 10.1 3.9 194 0.27
Table 61. Mean rotational traction values for blocks acrossloading weights in Experiment 6.a, inside and outsidethe hashmark, using the studded shoe.
Yard ------ degrees of rotation-------lines 10 20 30 40
Inside hashmark---------------- Nm ---------------
10 to 15 15.3 18.9 21.2 21.215 to 20 14.7 18.2 20.8 21.020 to 25 14.2 18.0 20.4 20.7
Isd (0.05) NS NS NS NS .
Outside hashmark
10 to 15 14.2 17.6 19.5 19.815 to 20 14.4 18.3 20.0 20.420 to 25 14.2 17.7 20.0 20.4
Isd (0.05) NS NS NS NS
Table 62. Mean rotational traction values for blocks acrossshoe types in Experiment 6.b, inside and outside thehashmark, using a 116 kg loading weight.
Yard ------ degrees of rotation ------lines 10 20 30 40
Inside hashmark---------------- Nm ---------------
10 to 15 20.5 26.5 30.1 29.915 to 20 20.3 26.0 29.5 29.720 to 25 19.1 24.9 28.5 29.3
lsd (0.05) NS NS NS NS
Outside hashmark
10 to 15 19.5 25.1 27.1 27.915 to 20 20.5 27.1 29.9 29.420 to 25 20.3 26.0 28.8 30.8
lsd (0.05) NS NS NS NS
...........o
Table 63. Mean rotational traction values for blocks acrosssoil water treatments in Experiment 6.c, inside andoutside the hashmark, using a 116 kg loading weightand the molded shoe.
Yard ------ degrees of rotation-------lines 10 20 30 40
Inside hashmark---------------- Nm ---------------
10 to 15 22.3 29.4 33.1 33.115 to 20 21.9 0.0 32.2 32.220 to 25 21.0 28.7 31.8 32.4
lsd (0.05) NS NS NS NS
Outside hashmark
10 to 15 21.2 27.8 30.8 31.715 to 20 21.9 28.5 32.9 33.620 to 25 22.3 28.8 32.2 32.4
lsd (0.05) NS NS NS NS
-"-
172
Table 64. Mean rotational traction values for the designatedvariables for the ~ombined Experiments, inside andoutside the hashmarks, for loading weightsin Experiment 6.a.
Variable ------ degrees of rotation ------10 20 30 40
Loading weight---------------- Nm ---------------
116 kg 16.9 21. 6 24.4 24.888 kg 14.8 18.5 20.8 21.1
59.9 kg 11.7 14.2 15.7 15.8lsd (0.05) 0.7 1.0 1.1 1.2
-------------------------------------------------------------Experiment
Inside hashOutside hash
lsd (0.05)
14.714.2NS
18.417.8NS
20.819.80.9
21.020.21.0
-------------------------------------------------------------
Interaction
Loading Hashweight mark
59.9 kg Inside 12.1 14.6 16.2 16.259.9 kg Outside 11.3 13 .8 15.3 15.488 kg Inside 15.3 19.0 21.2 21.588 kg Outside 14.3 18.0 20.4 20.8116 kg Inside 16.7 21.5 23.6 25.3116 kg Outside 17.1 21.7 23.8 24.4
lsd (0.05) NS NS NS NS NS
173
Table 65. Mean rotational traction values for the designatedvariables, for the combined experiments, inside andoutside the hashmark, for shoe types inExperiment 6.b.
Variable ------ degrees of rotation ------10 20 30 40
Shoe type---------------- Nm ---------------
Molded shoe 23.2 30.3 33.5 34.1Studded shoe 16.9 21.6 24.4 24.8lsd (0.05) 1.4 1.5 2.1 2.4
-------------------------------------------------------------Experiment
Inside hashOutside hash
lsd (0.05)
20.020.1NS
25.826.1NS
29.428.6NS
29.629.4NS
-------------------------------------------------------------
Interaction
Shoe Hashtype mark
Molded shoe inside 23.2 30.2 33.7 34.0Molded shoe outside 23.1 30.4 33.4 34.3Studded shoe inside 16.7 21.5 25.0 25.3Studded shoe outside 17.1 21.7 23.8 24.4lsd (0.05) NS NS NS NS NS
174
Table 66. Mean rotational traction values for the designatedvariables, for the combined experiments, inside andoutside the hashmark, for soil waterin Experiment 6.c.
Variable ------ degrees of rotation ------10 20 30 40
Soil water
Pre-precipitationPost-precipitation
lsd (0.05)
23.2 30.320.4 26.81.8 2.4
Nm ---------------33.5 34.130.8 31.02.2 2.2
-------------------------------------------------------------Experiment
Inside hashOutside hash
lsd (0.05)
21.821.8NS
28.728.4NS
32.432.0NS
32.532.5NS
-------------------------------------------------------------
Interaction
Soil Hashwater mark
Pre-precip. Inside 23.2 30.2 33.7 34.0Pre-precip. Outside 23.1 30.4 33.4 34.3Post-precip. Inside 20..3 27.2 31.0 31.1Post-precip. Outside 20.5 26.3 30.5 30.8
lsd (0.05) NS NS NS NS NS
Table 67. Plot characteristics for individual experimental units in Experiment 6 bothpre- and post-precipitation.
Shear Infil. Bulk Soil Tiller VerdureYard marker Precipe Hash. Hardness resistance rate density water density weight
g-max Nm cm/hr g/cm3 kg/kg no. /plug grams10 to 15 pre in 105 13.5 3.6 1.61 13.5 45 1.4
post in 92.5 16.5 16.915 to ~O pre in 100.3 14.5 3.3 1.59 13.9 67 1.1
post in 85.7 16.3 17.320 to 25 pre in 100.9 14.9 1.0 1.58 15.2 55 1.3
post in 75.9 17.0 20.310 to 15 pre out 86.1 16.3 9.7 1.61 13 .2 64 1.4
post out 75.7 16.7 15.815 to 20 pre out 86.5 16.2 20.3 1.59 12.4 55 1.6
post out 83.5 15.3 15.620 to 25 pre out 86.3 16.7 11.4 1.56 12.7 48 1.3
post out 77.7 16.5 15.9