1. Soils 101- Physical properties

2. Soils 101- Physical properties
It’s more than just “dirt”

3. Introduction – Why should I care?

4. Introduction – Why should I care?
Different soil types have unique properties

5. Introduction – Why should I care?
Different soil types have unique properties
Those properties, along with environment, affect tree survival and growth

6. Introduction – Why should I care?
Different soil types have unique properties
Those properties, along with environment, affect tree survival and growth
Planting the wrong tree for the site is a waste of time and $

7. Introduction – Why should I care?
Different soil types have unique properties
Those properties, along with environment, affect tree survival and growth
Planting the wrong tree for the site is a waste of time and $
Soil physical properties – the first thing to know about a site

8. Photos courtesy of Dave Hopkins, NDSU
Barnes soil
Photos courtesy of Dave Hopkins, NDSU

9. Photos courtesy of Dave Hopkins, NDSU
Barnes soil
Bowdle soil
Photos courtesy of Dave Hopkins, NDSU

10. Soil components

11. Soil components
Solids and pores

12. Soil components
Solids and pores
Solids – Minerals + Organic matter

13. Soil components Solids and pores Solids – Minerals + Organic matter
Pores – Water + Air

14. Soil components Solids and pores Solids – Minerals + Organic matter
Pores – Water + Air
Ideal soil – Even mix of solids and pores ...

15. Mineral 45%
Organic 5%
Brady, 1990

16. Soil components Solids and pores Note:
Solids – Minerals + Organic matter
Pores – Water + Air
Ideal soil – Even mix of solids and pores ...
Note:
Minerals – Sand (largest), silt, clay (smallest)

17. Soil components Solids and pores Note:
Solids – Minerals + Organic matter
Pores – Water + Air
Ideal soil – Even mix of solids and pores ...
Note:
Minerals – Sand (largest), silt, clay (smallest)
Pores – Even mix of water and air

18. Soil components Solids and pores Note:
Solids – Minerals + Organic matter
Pores – Water + Air
Ideal soil – Even mix of solids and pores ...
Note:
Minerals – Sand (largest), silt, clay (smallest)
Pores – Even mix of water and air
Organic matter is good stuff ...

19. Organic matter Holds onto water Great source of nutrients
Binds soil particles together into larger aggregates

20. Texture

21. Texture
Relative amount of sand, silt and clay only

22. Texture Relative amount of sand, silt and clay only
Lots of one part – soil named by that part

23. Texture Relative amount of sand, silt and clay only
Lots of one part – soil named by that part
e.g., 20% sand, 20% silt, 60% clay – clay

24. Texture Relative amount of sand, silt and clay only
Lots of one part – soil named by that part
e.g., 20% sand, 20% silt, 60% clay – clay
e.g., 12% sand, 82% silt, 6% clay – silt

25. Texture Relative amount of sand, silt and clay only
Lots of one part – soil named by that part
Mixtures are called loams

26. Texture Relative amount of sand, silt and clay only
Lots of one part – soil named by that part
Mixtures are called loams
e.g., 40% sand, 40% silt, 20% clay – loam

27. Texture Relative amount of sand, silt and clay only
Lots of one part – soil named by that part
Mixtures are called loams
e.g., 40% sand, 40% silt, 20% clay – loam
e.g., 33% sand, 33% silt, 34% clay – clay loam

28. Texture triangle

29. Example:
20% sand
60% clay
20% silt

30. Example:
20% sand
60% clay
20% silt

31. Example:
20% sand
60% clay
20% silt

32. Example:
20% sand
60% clay
20% silt

33. Example:
20% sand
60% clay
20% silt
Clay soil

34. Example:
62% sand
15% clay
23% silt
???? soil

35. Example:
62% sand
15% clay
23% silt
sandy loam soil

36. Texture
Relative amount of sand, silt and clay only
WHY SHOULD I CARE?

37. Texture Relative amount of sand, silt and clay only WHY SHOULD I CARE?
Different soil types have unique properties
Those properties, along with environment, affect tree survival and growth
Planting the wrong tree for the site is a waste of time and $

38. Pore Space

39. Pore Space
Size matters

40. Pore Space
Size matters – macropores and micropores

41. Pore Space
Size
Macropores – large, water drains easily

42. Macropores
Brady, 1990

43. Pore Space Size Macropores – large, water drains easily
Micropores – small, water held tightly

44. Macropores
Micropores
Brady, 1990

45. Pore Space Size Texture effects
Macropores – large, water drains easily
Micropores – small, water held tightly
Texture effects

46. Pore Space Size Texture effects
Macropores – large, water drains easily
Micropores – small, water held tightly
Texture effects
Sands – lots of macropores

47. Pore Space Size Texture effects
Macropores – large, water drains easily
Micropores – small, water held tightly
Texture effects
Sands – lots of macropores
Clays – lots of micropores

48. Pore Space Size Texture effects
Macropores – large, water drains easily
Micropores – small, water held tightly
Texture effects
Sands – lots of macropores
Loam – mixture of macro- and micropores
Clays – lots of micropores

49. Effect on infiltration and water availability?
Pore Space
Size
Macropores – large, water drains easily
Micropores – small, water held tightly
Texture effects
Sands – lots of macropores
Loam – mixture of macro- and micropores
Clays – lots of micropores
Effect on infiltration and water availability?

50. McLaren & Cameron

51. Steady infiltration rate inches/hour
Textural class
Steady infiltration rate inches/hour
Sands
>0.8
Sandy loams
Loams, fine sandy loams
Clay loams, silty clay loams and clays
Sodic clay soils
<0.04
Hillel, 1982 An Introduction to Soil Physics

52. Water drains out of macropores
Brady, 1990
Water drains out of macropores

53. Water drains out of macropores
Brady, 1990
Water drains out of macropores
Water held tightly in micropores

54. Water drains out of macropores
Brady, 1990
Water drains out of macropores
Water held tightly in micropores

55. Water drains out of macropores
Brady, 1990
Water drains out of macropores
Effect of soil texture on available water?
Water held tightly in micropores

56. Water drains out of macropores
Brady, 1990
Water drains out of macropores
Water held tightly in micropores

57. Pore Space Size Texture effects Where do roots grow?
Macropores – large, water drains easily
Micropores – small, water held tightly
Texture effects
Where do roots grow?

58. Brady, 1990

59. Pore Space Size Texture effects Where do roots grow?
Macropores – large, water drains easily
Micropores – small, water held tightly
Texture effects
Where do roots grow?
“Bulk density” – an indicator of pore space

60. Bulk density = (Weight of soil particles)
(Volume of soil (solids + pores))

61. Bulk density = (Weight of soil particles)
High bulk density
Low pore space
Low bulk density
High pore space
Bulk density = (Weight of soil particles)
(Volume of soil (solids + pores))

62. Pore Space Size Texture effects Where do roots grow?
Macropores – large, water drains easily
Micropores – small, water held tightly
Texture effects
Where do roots grow?
“Bulk density” – an indicator of pore space
Compaction –
Decreases pore space, esp. macropores
Increases bulk density

63. Pore Space
Size
Macropores – large, water drains easily
Micropores – small, water held tightly
Continuity – Water drains better if soil texture is consistent and continuous

64. The sponge example The sponge example The sponge example

65. Pore Space Another way to look at it is
Size
Macropores – large, water drains easily
Micropores – small, water held tightly
Continuity – Water drains better if soil texture is consistent and continuous
Another way to look at it is
Water does not move well from one soil texture to another

66. Pore Space Another way to look at it is
Size
Macropores – large, water drains easily
Micropores – small, water held tightly
Continuity – Water drains better if soil texture is consistent and continuous
Another way to look at it is
Water does not move well from one soil texture to another
Ever heard of the “teacup effect”?

67. Pore Space Size Texture effects Where do roots grow?
Macropores – large, water drains easily
Micropores – small, water held tightly
Texture effects
Where do roots grow?
“Bulk density” – an indicator of pore space
WHY SHOULD I CARE?

68. Pore Space Size Texture effects Where do roots grow?
Macropores – large, water drains easily
Micropores – small, water held tightly
Texture effects
Where do roots grow?
“Bulk density” – an indicator of pore space
WHY SHOULD I CARE?
Different soil types have unique properties
Those properties, along with environment, affect tree survival and growth
Planting the wrong tree for the site is a waste of time and $

69. Applications

70. Applications
What trees can survive on sandy soils?

71. Drought-tolerant deciduous shrubs
silver buffaloberry
caragana
common lilac
silverberry

72. Drought-tolerant hardwood trees
green ash
Russian olive
Siberian elm
bur oak

73. Drought-tolerant conifers
Rocky Mountain juniper
ponderosa pine
Eastern red-cedar

74. Applications What trees can survive on sandy soils?
What species can survive on wet, poorly drained soils?

75. Native trees and shrubs commonly found in wet, poorly drained soils.
American elm
green ash
boxelder
American linden
willows
cottonwood
ironwood (hophornbeam)
chokecherry
redosier dogwood
juneberry
False indigo

76. What species will NOT survive in wet, poorly drained soils?
Colorado (blue) spruce
common lilac
ponderosa pine

80. Applications What trees can survive on sandy soils?
What species can survive in wet, poorly drained soils?
What happens to pore space when a soil gets compacted?

81. Brady, 1990

82. Applications What trees can survive on sandy soils?
What species can survive on clay soils?
What happens to pore space when a soil gets compacted?
Bulk density increases (total pore space decreases)
Greater percentage of micropores

83. Applications What trees can survive on sandy soils?
What species can survive on clay soils?
What happens to pore space when a soil gets compacted?
Bulk density increases (total pore space decreases)
Greater percentage of micropores
Soil compaction  reduced tree health
Might need to break up compacted soils

84. Colorado blue spruce in the yard at a rural farmstead
Colorado blue spruce in the yard at a rural farmstead. And whatever is killing this tree is “moving down the row.”

85. Colorado blue spruce in the yard at a rural farmstead
Colorado blue spruce in the yard at a rural farmstead. And whatever is killing this tree is “moving down the row.”

86. Colorado blue spruce in the yard at a rural farmstead
Colorado blue spruce in the yard at a rural farmstead. And whatever is killing this tree is “moving down the row.”

87. Colorado blue spruce – the issue is soil fill from construction of the new home resulted in the roots of these trees being covered, thus killing the roots, and therefore the trees.

88. Applications What trees can survive on sandy soils?
What species can survive on clay soils?
What happens to pore space when a soil gets compacted?
Bulk density increases (total pore space decreases)
Greater percentage of micropores
Soil compaction  reduced tree health
Might need to break up compacted soils

89. Soils 101- Physical properties
It’s more than just “dirt”
 Questions?

90. Back to the canning jars ...

91. Sand
Clay
Silt

92. Back to the canning jars ...
Measure height of each component
Fill in calculations
Determine soil texture

93. Component Height (inches)
Component Percent
Sand
Clay
Silt A B
+C _____ D
(A/D) x 100
________%
(B/D) x 100
(C/D) x 100 +______%
100%

94. Soil samples Sample Soil type WSG % clay A Williams/Bowbells loam
3 (1)
18-27 B
Bowdle/Lehr loam 6G
10-27 C
Bearpaw/Zeeland loam 4 D
Parnell silty clay loam 2
27-40 E
Zahl/Williams loam
10 (3) F
Heimdal loam ? G
Greenhouse loam
N/A H
Play sand I
(G + H)

95. Before we even begin ...

96. Before we even begin ...

97. Before we even begin ...
Place soil sample in jar

98. Before we even begin ... Place soil sample in jar
Add 1 teaspoon of Calgon

99. Before we even begin ... Place soil sample in jar
Add 1 teaspoon of Calgon
Add water to within ~1/2” of top

100. Before we even begin ... Place soil sample in jar
Add 1 teaspoon of Calgon
Add water to within ~1/2” of top
Fasten lid and band

101. Before we even begin ... Place soil sample in jar
Add 1 teaspoon of Calgon
Add water to within ~1/2” of top
Fasten lid and band
Shake for ~1/2 minute

102. Before we even begin ... Place soil sample in jar
Add 1 teaspoon of Calgon
Add water to within ~1/2” of top
Fasten lid and band
Shake for ~1/2 minute
LET IT SIT ...

103. Soils 101- Physical properties
Introduction
Components
Texture
Pore space
Applications