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<br />, U. S. BUR�U OF SOII.S CI,�SSIFICATIOPI SYSTEhI
<br />We use the U. S. Bureau of Soils method of soil classification which is baseci on the
<br />� texture of the soil, The texture of a soil is influenced byr the amouat of the various
<br />sizes of soil particles in. the soil. The soil particles are grouped into three
<br />particle size classifications as follows: U, 5. Standard
<br />`� Particle-Size Diameter of
<br />�articles Niillimeters) Sieve
<br />Classification 2.p ;o Ua05 #10 to #270
<br />i` Sand p,05 to 0.005 (Gannot be separated
<br />Silt by sieving)
<br />'Clay Smaller than 0.005 ,
<br />Soil is grouped into twe?ve ba.s�c classifications according to hownPbrCtheafollo ng d�
<br />,o silt and clay present in the soi7_. These classifications are s y
<br />triaxial graph. 1�O�o 0
<br />,� .
<br />`� . .
<br />� SILT
<br />CI�Y
<br />.��, �.
<br />5o c�Y 50
<br />; �. :. . : _ ILTY
<br />NDY CIAY 70
<br />';� . . . �� �� 1 � . , .
<br />" SkND`l GIAY LOf�M SILTY
<br />"`� .� 2p GLAY LOAM CI�Y LOAM 80
<br />SANDY LO��r2 SILTY
<br />, � .`: 10 � �,QA�! LOAM
<br />, .Y,� ' SILT 100�
<br />� � ,Q 20 �
<br />100 90 $0 Sti�D .
<br />�
<br />r,s�� ;s Th�,s sam� classificatian systein in tabular form is as Follows;�
<br />` '� � BASIC SOIL CLf�SSIFICATIOtJ �ND ` SILT ��Y ,
<br />n■ :
<br />� k, . Sand • 90 - 100� 0- 10 Q_�O
<br />, �} 80-90 a-zo a
<br />� � , yoam�r sand _ � _ 20
<br />'` Sandy , loam 5Q - 80 0- 5�
<br />30 _ 50 •30 - 5� o za
<br />� _
<br />� � Loanl 0 - 20
<br />, -, �� 0�50 5a-�
<br />�, } .� �. : silty �oam
<br />r- =� ,, siit -. o- zo go - l oo a- 2a
<br />7�z�, 0-8� �-��� 2�-3�
<br />, .., : Saix�y clay loam ' S 20 - 30
<br />�a`�,, ` �� �'. y l ay lo a m 20 - 5� 20 50
<br />,�r� o_ 3� 5 0 _ so zo - 30
<br />�'�� � � � Silty clay" loam - : 0- 5Q 0 � �3� - 100
<br />;� ��. � CTa � � � � � �_
<br />� �� ; � �
<br />Sa�ridy clay' 50 -?Q o- 2 0 3 � -. 5 � �
<br />p3w��r a' , 5, _ o_ z o 5 0 - 70 3� -- 50
<br />� , A , Silty clay
<br />,����} U V , .
<br />'� '; l'_ �We cla5s�i the sand present in a soi: l as coarse (#� 1 0 -� 2 Q s i s v e s) , m e� d�Y��#20��40
<br />1� s�'f f.� �. t . V..: � .
<br />''��� �-��:�,-`,w�z�v�s�,,� f�e ,(�40 _' �10� sieves� , vezy .iine (#lOfl - �27� sieves} , or s g
<br />�.rFr ��ahn rfit y, � . . . ; . . .. � _ ��.:
<br />� �Y�;�;��,�+��.ls w�:th a�n appreci:able amount of ravel resent are cl.ass�.fied "with a little gravel"
<br />W A
<br />�'�r�$i } � t'with sc�me grave�.". (15 ta 30`,�) s"�rith gravel" i30 to 50�) }"anrl gr�vel
<br />:�°���Lsss t�an �5`�).�.
<br />s��,� (�q�� ��}y. Materia3 over 3 inches is classiiieci as boulders. Orgar�ic soil is c3.assified`
<br />�'����'��;8�t!� °�aver zI3 arganic material) or „muck" t 1 �3 to 2 f 3 organic material) .
<br />: , �,� ,. _
<br />� .��� �� ��� �.� _
<br />"'rc ����,�,� �
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<br />.�5;�,{ ��,� r�a� p .. . . .
<br />_ . ' ..i �*Hr�" � ti ��� 4 . .. ,. . .. .. . � :�a
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