ASTM F2396-11(2019)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: F2396 − 11 (Reapproved 2019) Am American National Standard
Standard Guide for
Construction of High Performance Sand-Based Rootzones
for Athletic Fields
This standard is issued under the fixed designation F2396; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
1.1 Thisguidecoverstechniquesthatareappropriateforthe
mendations issued by the World Trade Organization Technical
construction of high performance sand-based rootzones for
Barriers to Trade (TBT) Committee.
sports fields. This guide provides guidance for the selection of
materials, including soil, sand, gravel, peat, and so forth, for
2. Referenced Documents
use in designing and constructing sand-based sports turf
2.1 ASTM Standards:
rootzones.
C88Test Method for Soundness of Aggregates by Use of
1.2 Decisions in selecting construction and maintenance
Sodium Sulfate or Magnesium Sulfate
techniques are influenced by existing soil types, climatic
C131Test Method for Resistance to Degradation of Small-
factors,levelofplay,intensityandfrequencyofuse,equipment
SizeCoarseAggregatebyAbrasionandImpactintheLos
available, budget and training, and the ability of management
Angeles Machine
personnel.
C1444Test Method for Measuring the Angle of Repose of
1.3 This guide offers an organized collection of information
Free-Flowing Mold Powders (Withdrawn 2005)
oraseriesofoptionsanddoesnotrecommendaspecificcourse
D422TestMethodforParticle-SizeAnalysisofSoils(With-
of action. This document cannot replace education or experi-
drawn 2016)
ence and should be used in conjunction with professional
D698Test Methods for Laboratory Compaction Character-
judgment.Notallaspectsofthisguidemaybeapplicableinall
istics of Soil Using Standard Effort (12,400 ft-lbf/ft (600
circumstances. This guide is not intended to represent or
kN-m/m ))
replace the standard of care by which the adequacy of a given
D1883Test Method for California Bearing Ratio (CBR) of
professional service must be judged, nor should this document
Laboratory-Compacted Soils
be applied without consideration of a project’s many unique
D1997Test Method for Laboratory Determination of the
aspects. The word “standard” in the title of this document
Fiber Content of Peat Samples by Dry Mass
means only that the document has been approved through the
D2944Practice of Sampling Processed Peat Materials
ASTM consensus process.
D2974Test Methods for Moisture,Ash, and Organic Matter
of Peat and Other Organic Soils
1.4 The values stated in SI units are to be regarded as the
D2976Test Method for pH of Peat Materials
standard. The values in parentheses are for information only.
D2980 Test Method for Saturated Density, Moisture-
1.5 This standard may involve hazardous materials,
Holding Capacity, and Porosity of Saturated Peat Materi-
operations, and equipment. This standard does not purport to
als
address all of the safety concerns, if any, associated with its
D3080Test Method for Direct Shear Test of Soils Under
use. It is the responsibility of the user of this standard to
Consolidated Drained Conditions
establish appropriate safety, health, and environmental prac-
D4427ClassificationofPeatSamplesbyLaboratoryTesting
tices and determine the applicability of regulatory limitations
D4972Test Methods for pH of Soils
prior to use.
F1632Test Method for Particle Size Analysis and Sand
1.6 This international standard was developed in accor-
Shape Grading of Golf Course Putting Green and Sports
dance with internationally recognized principles on standard-
1 2
This guide is under the jurisdiction of ASTM Committee F08 on Sports For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Equipment, Playing Surfaces, and Facilities and is the direct responsibility of contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Subcommittee F08.64 on Natural Playing Surfaces. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Dec. 1, 2019. Published January 2020. Originally the ASTM website.
approved in 2004. Last previous edition approved in 2011 as F2396–11. DOI: The last approved version of this historical standard is referenced on
10.1520/F2396-11R19. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F2396 − 11 (2019)
Field Rootzone Mixes if a dense, uniform turf cover is maintained, the sand-based
F1647Test Methods for Organic Matter Content ofAthletic system can provide a very stable, firm, smooth, and uniform
Field Rootzone Mixes playing surface. A successful sand-based rootzone system is
F1815Test Methods for Saturated Hydraulic Conductivity, dependent upon the proper selection of materials to use in the
Water Retention, Porosity, and Bulk Density of Athletic project.The proper selection of sand, organic amendment, soil
Field Rootzones and gravel is of vital concern to the performance of the system
F2060Guide for Maintaining Cool Season Turfgrasses on and this guide addresses these issues.
Athletic Fields 4.1.1 During construction, consideration should be given to
F2107Guide for Construction and Maintenance of Skinned factors such as the physical and chemical properties of mate-
Areas on Baseball and Softball Fields rials used in the area, freedom from stones and other debris,
F2269Guide for Maintaining Warm Season Turfgrasses on and surface and internal drainage.
Athletic Fields 4.1.2 Maintenancepracticesthatinfluencetheplayabilityof
F2651Terminology Relating to Soil and Turfgrass Charac- the surface include mowing, irrigation, fertilization, and me-
teristics of Natural Playing Surfaces chanical aeration and are factors addressed in other standards
(see Guides F2060 and F2269).
3. Terminology
4.2 Those responsible for the design, construction, or
3.1 Definitions: maintenance, or a combination thereof, of natural turf athletic
3.1.1 Except as noted, soil-related definitions are in accor- fields for high-performance, all-weather purposes will benefit
dance with Terminology F2651. from this guide.
4.3 Asuccessful project development depends upon proper
NOTE 1—Particle size ranges for sand, silt, and clay used in this
standard vary somewhat from ranges given in Test Method D422.
planning and upon the selection of and cooperation among
design and construction team members. A high-performance,
4. Significance and Use
sand-based rootzone project design team should include a
projectdesigner,anagronomistorsoilscientist,orboth,andan
4.1 A dense, uniform, smooth, and vigorously growing
owner’s representative. Additions to the team during the
natural turfgrass sports field provides the ideal and preferred
construction phase should include an owner’s project manager
playing surface for most outdoor field sports. Such a surface is
(often an expansion of role for the owner’s representative), an
pleasing to the spectators and athletes.Athick, consistent, and
owner’s quality control agent (often the personnel that is
smoothgrasscoveralsoincreasesplayingqualityandsafetyby
employed in advance with the intent of becoming the finished
providing stable footing for the athletes, cushioning their
project’s sports field manager), an owner’s testing agent (often
impact from falls, slides, or tackles, and cools the playing
an expansion of roles for the project’s agronomist/soil
surface during hot weather. Sand is commonly used to con-
scientist), and the contractor.
struct high performance sports turf rootzone systems. Sand is
4.3.1 Planning for projects must be conducted well in
chosen as the primary construction material for two basic
advance of the intended construction date. This often requires
properties, compaction resistance and improved drainage/
numerous meetings to create a calendar of events, schedule,
aeration state. Sands are more resistant to compaction than
approvals, assessments, performance criteria, material
finer soil materials when played upon within a wide range of
sourcing, geotechnical reports, and construction budgets.
soilmoistureconditions.Aloamysoilthatmayprovideamore
stable surface and enhanced growing media compared to sand
NOTE 2—Other specifications on soils for athletic field construction
under optimal or normal conditions will quickly compact and
havebeenpublishedandhavebeenconsideredduringthedevelopmentof
deteriorate in condition if used in periods of excessive soil this guide.
moisture, such as during or following a rainy season. A
5. Construction
properly constructed sand-based rootzone, on the other hand,
will resist compaction even during wet periods. Once 5.1 The steps to be used in construction of a new athletic
compacted, sands are easier to decompact with the use of field include:
mechanical aeration equipment. Even when compacted, sands 5.1.1 Survey and stake the site to establish subgrade and
willretainanenhanceddrainageandaerationstatecomparedto finish grade elevations.
native soil rootzones under the same level of traffic. As such, 5.1.2 Constructandpreparesubgrade,andprovideacorrect
sand-based rootzones are more conducive to providing an and certified subgrade.
all-weather type of playing surface. Properties of both the soil 5.1.3 Install subsurface drainage system, frame out warning
and grass plants must be considered in planning, constructing, tracks, skinned areas, and so forth, as appropriate.
and maintaining a high quality sports turf installation. Turf- 5.1.4 Install irrigation system (irrigation system may be
grass utilized must be adapted to the local growing conditions installed prior to rootzone installation).
and be capable of forming a thick, dense, turf cover at the 5.1.5 Prepare for rootzone installation.
desiredmowingheight.Unvegetatedsandinandofitselfisnot 5.1.5.1 Secure suitable sand, properly tested and approved.
inherently stable; therefore, it is imperative that grasses with 5.1.5.2 Blend any amendments with sand to project
superior wear tolerance and superior recuperative potential are specifications, approve using QC program.
utilizedtowithstandheavyfoottrafficandintenseshearforces. 5.1.5.3 Install approved gravel (if included in design).
Sanddoes,however,haveincredibleloadbearingcapacityand 5.1.6 Install rootzone blend.
F2396 − 11 (2019)
5.1.7 Bring field to final grade and contour in accordance installation of drainage system. Subgrade shall be re-surveyed
with specifications, compact to specifications. and certified prior to gravel or rootzone import.
5.1.7.1 A pre-plant fertilizer application may be applied at 5.4.2 Surface Drainage—To maintain adequate surface
this point as specified. drainage, all field installations should include a minimum of
0.5% slope gradient (simple slope or crown) to remove water
5.1.8 Establish turf by appropriate methods (seed, sprigs,
off of the playing field in case of a storm event with severe
plugs or sod).
rainfall intensity and to facilitate the use of tarps. It is
5.1.9 Fertilizetheinstallationasappropriatebaseduponsoil
recommended that an adequate number of small size surface
testing.
drainage inlets be installed in the perimeter of the installation
5.1.10 Turf is to be established based upon grow-in recom-
(in out-of-play areas) and tied into the drainage collection
mendations from a competent agronomist or soil testing
system for removal of surface runoff with the subsurface
laboratory, as appropriate for the turf species utilized and the
drainage water.
climate of the site.
NOTE 3—In planning and designing projects, consideration shall be
5.2 Survey and Stake—This procedure should be done to
given to the permeability of the rootzone when determining the slope of
conform to the project designer’s specifications as appropriate
the finished surface and the need for adjacent surface drainage systems.
for the sport. In the case of the construction of a replacement
Further consideration shall be given in cold climates where frost penetra-
field, this step may be deleted or modified as appropriate. Care
tion may impact the permeability of the rootzone when determining the
slope of the finish surface and the need for adjacent surface drainage
should be taken to protect staking during the construction
systems. Generally, the need for improved surface drainage increases as
process.
the permeability of the rootzone decreases.
5.3 Construct and Prepare Subgrade—Contour the sub-
5.4.3 Sub-Surface Drainage Material—Three recom-
grade in accordance with specifications at a suggested toler-
mended options exist for the use of drainage material. Option
anceof 612.5mm( ⁄2in.)within3m(10ft)oflineardirection
1 could utilize sand rootzone material to backfill around
as specified in 5.5.6. The subgrade should be installed at a
drainlines within the drainage trenches. Option 2 could utilize
depth such to accommodate the final profile depth of rootzone
gravel material to backfill around drainlines in the drainage
and any gravel layer (if included). The subgrade should be
trenches. Option 3 could include the use of gravel to backfill
compacted sufficiently (suggested 85% minimum to 90%
around drainlines in drainage trenches and to form a drainage
maximum proctor density) to prevent future settling. Subgrade
layer overlying the subgrade before placement of rootzone
should be designed to conform to surface contour of finished
sand blend. All backfill treatments shall be compacted to
playing surface.
specifications prior to further installation procedures. It is
recommended that backfill for trench bottoms is installed and
5.4 Subsurface Drainage System—Many types of designs
compacted prior to installing drain pipe into the trenches. It is
exist for subsurface drainage most commonly including a grid
recommended that the trench bottom remain unobstructed as
or herringbone pattern. The project specifications should in-
installed and no soil pilings, wood blocks, concrete or metal
clude a subsurface drainage design to facilitate drainage for a
blocksareusedtoadjustandmaintainslopeofdrainlines.Any
25 year storm event. Most commonly used drainage systems
blocks used for this purpose must be removed from under the
forsand-basedathleticfieldsincludeutilizingperforateddrain-
lines 10 cm (4 in.) in a 4.5 m (15 ft) to 6 m (20 ft) spacing drainlines and any cavities backfilled before proceeding. It is
recommended that drainage trenches (bottom and sides only)
between drainline laterals.
should be lined with a woven geosynthetic filter fabric to
5.4.1 Drainline Trenches—Trenches constructed for drain-
preventcontamination(lateralmovementofsubgradematerials
linesshouldbeexcavatedintoaproperlyprepared,graded,and
intotrenchfill).Geosyntheticfilterfabricshould notbeusedto
compacted subgrade. Drainage trenches should be of a depth
coverthedrainagetrench.Itisrecommendedthatalldrainlines
suchtoconformtothedrainagecontours.Alldrainagetrenches
are installed straight (without ‘snaking’) within the trenches. It
anddrainlineinstallationsshouldmaintainaminimumpositive
is recommended that sleeves (of oversize PVC piping) should
slope gradient of ≥0.5% toward drainage outlets with trench
be installed across the drainage trenches at appropriate points
bottoms compacted to subgrade specifications. Drainage exca-
as indicated by the irrigation design to facilitate irrigation pipe
vationsshouldbemadesuchthataminimumof5cm(2in.)of
installation at points where the irrigation line crosses over the
bedding material can be contained around the installed drain-
drainage trenches.
line (below, to each side, and above). For example, a 10 cm (4
5.4.3.1 Option 1—Rootzone sand (with or without other
in.) diameter drainline installation will require a minimum
rootzone amendments) may be utilized to backfill around
dimension of 20 cm (8 in.) wide by 20 cm (8 in.) depth (for
drainlines.Ifsandisutilizedforthispurpose,thedrainagepipe
example, 10 cm drainline + (5 cm/side × 2 sides) = 20 cm; 10
used in these installations must be of a type that utilizes slitted
cm drainline+5cmtop+5cm bottom = 20 cm). Once
perforations with slit openings meeting a specification of D
drainage trenches are excavated, all excavated material should
sand/slot width >1.5, to reduce the potential for particle
be removed from the subgrade surface and disposed off site.
migration into the drainage system (1).
The subgrade should have no elevations of subgrade soil
material such to hinder the flow of water along the subgrade 5.4.3.2 Option 2—Gravel may be used for backfill of
interfaceintothedrainagetrench.Oncedrainagetrencheshave drainage trenches. If gravel is used for backfill, it should
been excavated, the trench bottoms should be sufficiently conform to the specifications in Table 1. Soft gravel minerals
compacted to the subgrade compaction specifications prior to (such as limestone, sandstone, or shale) are not acceptable for
F2396 − 11 (2019)
TABLE 1 Gravel Filter/Drainage Layer Specifications (1, 2)
5.4.3.5 Determination of Well-Aerated Rootzone
Performance Acceptable Conditions—A well-aerated rootzone is normally that portion
Criteria
Factor Value
of the rootzone that retains ≥20% air-filled porosity (AFP)
Filtering Factors D of gravel/D of rootzone mix <5
15 85
after gravitational drainage ceases (as determined at 40 cm
D of gravel/D of rootzone mix <25
50 50
tension).To determine the depth of sand required to obtain the
Permeability Factor D of gravel/D of rootzone mix $5
15 15
Uniformity Factors D of gravel/D of gravel #2.5
90 15 desired well-aerated profile depth, a soil moisture retention
>12 mm fraction 0 %
curve of the rootzone material must be determined. Consider-
<2 mm fraction #10 %
ingthattheperchedwateraboveagravellayerwillberetained
<1 mm fraction #5%
at a tension of approximately 10 cm tension, the moisture
retention status of the rootzone material should be considered
use and all questionable gravel material should be tested for
at tensions greater than 10 cm until the proportion of air-filled
weathering stability using the sulfate soundness test (see Test
poreswithintherootzonematerialreaches20%orgreater.For
MethodC88).Alossofmaterialgreaterthana12%byweight
example, let’s hypothesize that a soil moisture retention curve
isunacceptable.Likewise,anygravelmaterialthatissuspectin
shows that a material reaches 20% AFP at 21 cm tension. To
its mechanical stability should be tested utilizing the LA
providea15cmwell-aeratedrootzone,ourprofiledepthwould
Abrasion test (see Test Method C131). An LA Abrasion test
be 21 cm (AFPthreshold tension) – 10 cm (tension of perched
value greater than 40 is unacceptable.
water) + 15 cm of well-aerated rootzone, for a total rootzone
5.4.3.3 Option 3—Gravel may be used to backfill drainage
depth of 26 cm. Moisture retention points should be deter-
trenches and to form a drainage layer beneath the sand
mined utilizing methodologies in Test Method F1815.
rootzone. If gravel is used for this purpose, the same gravel
should be used for backfill and the drainage layer, and should 5.5 Sand-Based Rootzone—Materials used to provide the
conform to the specifications given in Table 1. Soft gravel sand for the rootzone shall meet the performance criteria
minerals are not acceptable for use and all questionable gravel
establishedinthisguide.Additionsofpeatorsoil,orboth,may
material should be tested for weathering stability using the be included in small proportions as part of the rootzone blend,
sulfate soundness test (see Test Method C88). A loss of
if the inclusion of these materials will not bring the resulting
material greater than 12 % by weight is unacceptable.
blend out of specifications and if they are uniformly blended
Likewise, any gravel material that is suspect in its mechanical
together to form a homogeneous blend.
stability should be tested utilizing the LA Abrasion test (see
5.5.1 Sand Type—Quartz sands are recommended; if sand
TestMethodC131).AnLAAbrasiontestvaluegreaterthan40
containsmorethan5%calciumcarbonateequivalent,thesand
is unacceptable.Agravel drainage layer should be a minimum
hasthepotentialforparticlecementationduetodissolutionand
of 7.5 cm (3 in.), with 10 cm to 15 cm (4 to 6 in.) preferred.
reprecipitation of carbonates. Other sands are not recom-
During installation, the gravel is typically dumped from the
mended due to their propensity to weather (by either mechani-
deliverytrucksontotheperimeter,andthendistributedoverthe
cal or chemical means, or both) over a relative short period of
construction site by a small, tracked, crawler tractor (or
time (1 to 5 years) that may influence the performance of the
similar), being careful to avoid driving over and crushing the
construction. For example, granitic material often contains
drainlines.Contourandcompactthegravelinaccordancewith
appreciable amounts of feldspar or mica which is much more
specifications at a suggested tolerance of 612.5 mm ( ⁄2 in.)
readilysubjecttoweathering.Cautionshouldbegiventosands
within 3 m (10 ft) of linear direction and as specified in 5.5.6.
that contain appreciable proportions of mica minerals. Mica
5.4.3.4 Discussion—If gravel is utilized as a drainage layer,
grainshaveaflatorplate-likemorphologyandredistributionof
it will improve the drainage of the system under conditions of
these grains with a rootzone profile may create layers that
saturated flow only. Saturated flow conditions typically only
impede drainage and aeration.
occur during intense or prolonged rainfall events. Under
5.5.2 Particle Size Distribution—Particlesizeanalyses(Test
unsaturated conditions, the use of a gravel layer will impede
Methods D422 or F1632) are based on oven-dried mass of a
drainageandwillservetoretainadditionalmoisturewithinthe
weighed sample; shaker is the preferred method of dispersion
rootzone profile. This condition is commonly referred to as a
to prevent fracturing of sand particles that may falsely influ-
‘perched’or ‘suspended’water table.The water perched in the
ence the sand size distribution. There are many published
rootzone at the interface with the gravel will be retained in a
specificationswithintheturfindustryforsandsizedistribution
condition nearing saturation. While such conditions may be
for sand-based rootzone constructions. Many of these specifi-
beneficial in terms of water conservation, care must be exer-
cations are primarily intended for golf green construction. As
cised in the design of the rootzone system, such that excessive
such, the amount of coarse material allowed is limited in order
moisture is not retained that could lead to anaerobic rootzone
to produce a very smooth surface under extremely short
conditions. Such conditions are common on poorly designed
mowing conditions to facilitate smooth roll of the small golf
gravel, underdrained, sand-based rootzone systems. If a gravel
ball. Such conditions are not required for athletic field con-
underdrain system is used, the design parameters should be
struction and the use of higher proportion of coarser sand
adjusted to assure a minimum of 15 cm (6 in.) of well aerated
materialcanbeutilized.Table2includesarecommendedsand
rootzone. If the capillary rise of salts or other contaminants
from the subgrade are of concern on a particular project, the particle size distribution (before amendments), but is not
inclusiveofallsizedistributionsofsandsthatcouldbeusedto
use of a gravel layer is recommended to prevent this occur-
rence. produce a high performance sand-based field. Additionally:
F2396 − 11 (2019)
TABLE 2 Recommended Particle Size Distribution of
up the rootzone material. This would most commonly include
A
Rootzone Sand
a blend with soil or peat, or both.
Size Particle Specified
5.5.4.1 Soil—Soil is commonly used as a component of a
Fraction Diameter Range Range (%)
sand-based rootzone construction in order to provide some
Gravel >4.75 mm 0 %
Gravel 3.4 to 4.75 mm <5 %
enhanced capacity for moisture and nutrient retention and
Fine gravel 2.0 to 3.4 mm <20 %
sometimestoimprovethemechanicalstabilityoftherootzone.
Very coarse sand 1.0 to 2.0 mm <20 %
Proportions of soil in a high performance rootzone mix
Coarse sand 0.5 to 1.0 mm 25 to 50 %
Medium sand 0.25 to 0.5 mm >25 % typically range from 5 to 15% by volume. The amount of soil
Fine sand 0.15 to 0.25 mm <10 %
to include in a blend depends upon the make-up of the soil
Very fine sand 0.05 to 0.15 mm <5 %
component, and the effects of the soil additions to the physical
Silt 0.002 to 0.05 mm <5 %
Clay <0.002 mm <3 %
performance characteristics of the resulting blend. Ideally, the
A
See 5.5.2.1 – 5.5.2.4 for additional recommendations. soil component would be one that is composed purely of clay.
Clay minerals generally have good moisture and nutrient
retention capacities, and if present in high enough proportions
may significantly improve rootzone stability by enhanced
5.5.2.1 No more than 30% in the combined very coarse
cohesiveproperties.Whenclayisincludedinablendwithsand
sand, fine gravel, and gravel fractions.
in the appropriate proportion, the clay will coat the sand and
5.5.2.2 At least 60% of the total sand should be in the
form bridges between sand grains without clogging up the
combined medium sand and coarse sand fractions.
large pores (interstitial pores or packing voids) of the sand
5.5.2.3 No more than 15% in the combined fraction less
matrix. If a pure clay source is used, many sands will
than0.25mm(finesand,veryfinesand,siltandclayfractions).
accommodate 10 to 15% clay additions without clogging.
5.5.2.4 ACoefficientofUniformity(CU=D /D )valueof
60 10
However, care must be used in the blending and preparation
2.5 to 4.5.
process because a small increase in clay content can cause a
5.5.3 Sand Shape—Although acceptable sand-based root-
drastic detrimental change in the performance of the rootzone.
zonescanbeconstructedwithsandsofallshapes,thisfactoris
This is a primary reason for a well-designed calibration and
worthconsiderationinathleticfieldconstruction.Sandshapeis
quality control program. Other soils may be used as a compo-
generally classed as to angularity and sphericity. Angularity
nentofasand-basedrootzoneblend,butshouldberestrictedto
includes well-rounded, rounded, subrounded, subangular,
those soil textures that are low in silt content. Silt is normally
angular, and very angular. Sphericity includes high sphericity,
a fine-grained, non-plastic soil material and is subject to
medium sphericity, and low sphericity. Sand shape should be
migration and layering. Soils that exhibit a silt to clay ratio
classified according to Figure 1 of Test Method F1632. While
greater than 2 should not be used. Likewise, those soils with a
no sand will have sand grains of uniform shape, there is
fines(silt+veryfinesand+finesand)toclayratiogreaterthan
normally a predominant shape of grains from a single sand
3shouldbeavoided.Generally,soilscontainingmorethan6%
source. The shape and dimension of sand grains affect its
organic matter should not be used, nor any mucky-type soils.
stability. For example, rounded grains are the least stable
Peat may be used to increase the organic matter content in a
becauseofthelackofedgestointerlockthegrains.Assuchthe
three-way blend of sand-soil-peat.
sand grains tend to act like small ball bearings.Angular sands
5.5.4.2 Peat—Peat is commonly used as an amending
to have greater stability because the sharper edges have a
source in a sand-based rootzone. Proportions of peat included
greatergrain-graininterlockandresistancetoshear.Sandsthat
in a blend (usually 15 to 20% by volume) should give an
have a predominance of grains that show extremes in angular-
organic matter content of 0.3 to 2.0% by mass.As with soils,
ity (extremely angular or extremely round) that fit outside the
peat adds water and nutrient retention capacity, but will add
classification in Test Method F1632 should be avoided.
little in terms of increased soil strength (cohesion). Peats can
Likewise, extremely high or low sphericity particles should be
also slow water movement through excessively drained sands.
avoided, including plate-like particles. Many dune sand
Finer peats, whether by decomposition or by finer grinding,
sources may contain sand grains that have internal fracture
generally have a greater effect on slowing water movement.
planes. During the saltation process, dune sands can become
Three sources of peat have been used successfully to modify
roundedastheyrollandskipalongthesurfaceasafunctionof
sands. They are moss peats (sphagnum and hypnum), reed-
the wind. However, during strong wind events, the grains can
sedge peats (derived from reeds, sedges, marsh grasses, and
be moved at a high velocity, whereby the grains impacting
other plants of the wetland), and peat humus, which is
upon each other develop ‘cracks’or fracture planes within the
grain.When rootzones are constructed with these sands, traffic decomposed peat (usually derived from moss or reed-sedge
sources). Peats to avoid in modifying sands are woody peat
and other weathering factors may cause the grains to fracture
alongtheseplanes,resultingintheformationofsilt-sizequartz (derived from trees and shrubs) and sedimentary peat (derived
from plants that grow in water and found on pond and lake
grains which may then be prone to particle migration and
subsequent accumulation in layers. Sand grains should be bottoms).Peatscanbeclassifiedaccordingtofibercontent(see
ClassificationD4427).Ingeneral,mosspeatsfallintothefibric
examined under 20 to 50× magnification for sand size, shape,
and potential fracture planes. classification, which indicates the greatest fiber content; reed-
5.5.4 Rootzone Amendments—Two types of amendments sedge peats into the hemic classification (a mid-range of fiber
arecommonlyincludedinablendwithsandthattogethermake content); and peat humus into the sapric classification (lowest
F2396 − 11 (2019)
TABLE 3 Suitability Ratings of Properties of Organic
sourcing and construction phases. Under strict control and
Amendments for Utilization in High Performance
testing, composts have and may be used for high performance
Sand-based Athletic Field Rootzones
sand-based rootzone constructions. It is recommended that
Rating\Property C/N Ratio Ash Content pH
only compost products be used that have been used success-
Preferred 20:1 to 30:1 <12 % 4.5 to 7.0
fully in high performance sand-based field mixes in the past,
Acceptable 30:1 to 50:1 12 to 17 % 3.5 to 4.5
Marginal 50:1 to 80:1 17 to 30 % 3.0 to 3.5 and only in amounts sufficient to meet the performance
Unacceptable, or use <20:1 or >80:1 >30 <3.0 or >7.0
parameters outlined in this guide. Mix design and testing
only with caution
should be performed by laboratories experienced in evaluating
composts and compost amended mixes.
5.5.4.4 Quality Control (QC) Program—Every high perfor-
fiber content). The acceptable sources of peat range in their
mancesand-basedrootzoneshouldbeconstructedusingawell
physical and chemical properties and information in Table 3
designed and administered calibrat
...