To be the best you have to beat the best!

Part 1 Physical Characteristics of the Soil

Surface soil and subsoil Surface soil or top soil - texture should be checked in the plow layer or the upper 7 inches of unplowed soil. The plow layer is a darker colored upper layer that has been mixed by tillage. Never check coarse unless told to and when in doubt check medium. Subsoil -is any soil below the surface soil. Samples for determining subsoil texture should be taken between 18 and 24 inches below the soil surface. If the soil is less than 24 inches to bedrock then it should be taken in the middle of the subsoil

Importance of soil texture Soil texture affects the (1)rate of water absorption, (2)water movement, (3)how much water the soil can absorb, (4)how much water the soil can supply to plants, and (5)how easily pollutants can leach into the groundwater. Soil texture also affects (6)ease of tillage, (7)erodibility, (8)fertilizer management and (9)root penetration. Soil texture can only be changed at great costs. Therefore it is one of the most important factors in soil judging.

Depth of Soil Favorable for Roots Rooting depth is the total depth of soil and parent material that will allow root penetration and growth through most of its volume. Deep_________+36 inches_________ o Moderately Deep____20-36 inches___O Shallow____________10-20 inches___O Very Shallow________-10 inches____O

Rock Fragments Rock fragments are loose pieces of rocks of any kind or shape larger than sand. None or Few_____less than 15%____O Common________15-35%_________O Many___________greater than 35%_O

Rock Outcrop Rock outcrops are hard, fixed exposures of bedrock. Limestone is the most common kind in Tennessee, but they may be any kind of rock. Rock outcrop are not movable with ordinary machinery. None or Few- less than 43 sq feet. Rocks are greater than 200 feet apart Common- Rocks take up 43 to 870 square feet of an acre. Rocks are 100 to 200 ft apart. Many-Rocks take up more than 870 square feet of an acre. Rocks are less than 100 feet apart.

Drainage Class Excessively Drained- No gray mottles, subsoils that have loamy texture with many rock fragments or subsoils that have coarse texture from the bottom of the plow layer to 36 inches. Well Drained- No mottles within 36 inches Moderately Well Drained- dominantly gray from 17 to 36 inches deep. Somewhat Poorly Drained- dominantly gray in the area below the plow layer(7in) to 17 in deep. Poorly Drained- dominantly gray within plow layer (top 7 inches). Most of the time soil will have a gray film over the entire profile.

Available Water Holding Capacity AWHC is the amount of water a soil can store and release for use by plants. Three things affect AWHC: Texture, Depth, Rock Fragments. Texture Coarse-.05 Medium-.20 Fine-.15 Multiply depth times the texture to figure AWHC Example: 36 deep and texture is Medium/ 36 X.20= 7.20 High AWHC

AWHC Continued If you have Rock Fragments in the soil you must account for them. Multiply the percentage of what is not rock fragments times the answer you get when you multiply depth times texture. Example: 36 inches deep, Medium Texture, 25 % rock fragments 36 X.20 X.75=5.4/Medium AWHC Low=3.99 or less Medium=4 to 5.99 High=6 or more

Erosion Erosion is the removal of soil material from the soil surface by flowing water or wind. None to slight- at least 75% of the original surface soil is present. (5 ¼ inches or greater of surface soil is present) Moderate- 25%-75% of the original surface soil is present. (1 ¾ -5 ¼ inches of surface soil) Severe- Less than 25% of the original surface soil is present. (Less than 1 ¾ inches of surface soil)

Soil Profile

Position Of Site on Landscape Landscape position refers to the location of a site relative to the landscape around it. Upland or Terrace- Will not flood Footslope- Will not Flood Floodplain- Will Flood Depression- Will Flood

Now you can sit under a shade tree and fill out the back side Land Class I-IV-Cropland-Can grow crops on these land classes Class V- Do not Check Class VI- Pasture ClassVII- Rocks and Non Fruit Production Trees Class VIII- Do Not Check

Land Class Continue This chart will always serve as starting land class. Land class can be no better for any reason than what this chart starts land class as. Erosion 0-2%2-5%5-12%12-20%20-30%<30% Greater Than 1 ¾” I II III IV VI VII Less than 1 ¾” II III IV VI VII Slope After you have determined starting land class you must check to see if any other physical characteristics will bump land class. They include: Texture, Depth, RO, RF, Drainage, and POS

Land Class Continued Bumping and at least as’s.(Don’t Bump on Top of Your Bumps) First rule. Only bump from the chart after you have initial land class. Texture: Both Texture Coarse then bump one land class Depth to rocks : Greater than 36in deep.-No Bump, 20-36in deep. Bump1land class, 10-20in deep. Bump 2 land classes, Less than 10in deep and Less than 12% slope at least a class VI and Greater than 12% slope at least a class VII Special rule for depth to clay or fragile pan, If depth is less than 24 in to heavy structure less clay or fragile pan Bump 1 land class. If deeper than 24 inches no bump.

Land Class Continue Rock Fragment N or F-No Bump Common-No Bump Many-Bump 1 land class Rock Outcrop N or F- No Bump Common-At least a class III Many-Same as Very shallow to bedrock. Less than 12% slope is at least class VI and greater than 12% slope is at least class VII.

Land Class Continue Drainage(NOT BUMP’s, They are at least as’s. Excessively Drained-at least Class II Well Drained-Class I Moderately Well Drained-at least class II Somewhat Poorly Drained-at least class III Poorly Drained-at least class IV

Land Class Continue Position of Site on Landscape If it will flood it is at least a class II. This includes floodplain and depression

Limitations Check limitation if there is a problem. When do you check them? Wetness-MWD, SWP, or PD soils Slope-Greater than 2% Texture of surface soil- coarse or fine Texture of Subsoil- coarse AWHC- less than 6 RF and RO- common or many Effective depth- less than 30in deep for any reason Flooding-if it will flood (depression or floodplain)

Estimated Crop LowMediumHigh Yields Corn Low AWHC, or Medium AWHC on D or greater slopes all other High AWHC A and B slope, except PD Cotton Low AWHC, or PD soils in Floodplains or Depressions all other Same as Corn Soybean Low AWHC all other High AWHC on ABC Slopes Tobacco Low AWHC, or Medium AWHC on D slopes, and on all PD and SWP Drained Soils all other High AWHC on AB Slopes that are well drained and do not flood.(Must have all this) Small Grain Low AWHC on slopes greater than 5%, or very shallow rooting depth, or PD/SWP drained soils that flood all other Soils that do not flood that are WD or MWD that have High AWHC on ABC slopes or Medium AWHC on AB slopes Alfalfa Low AWHC, or PD/SWP drained soils (they do not have to flood) or MWD soils that flood! all other High AWHC on ABC Slopes that are well drained and do not flood. (Must have all this) Fescue/White Clover Low AWHC with slopes greater 12%, and on soils with very shallow rooting depth all other High AWHC(slope does not matter), or Medium AWHC on ABC slopes

Potential Environmental Problems 1.Sediment, nutrients or pesticides in streams Low-0-2% slope or class VI and VII Medium-2-5% slope High-Greater than 5% slope\ 2. Nutrients or pesticides in groundwater Low-Deep(>36 in deep) or class VII land or any other soils that won’t fit into medium or high Medium-Moderately deep to bedrock with medium texture subsoil or medium texture subsoil with many rock fragments. High-Shallow or very shallow to bedrock. In other words anything less than 20in deep to bedrock is high.

Check the one most intensive recommended use. Continuous annual crops-minimal conservation system- check when class I-IV with slopes less than 2%. Continuous annual crops-intensive conservation system- check when class I-IV with slopes 2-5%. Annual crops in rotation with perennial grass/legume- check when class I-IV with slopes greater than 5%. Permanent grass/legume cover- check when class VI. Trees- check when class VII.

Recommended Practices 1. Drainage systems- <2% slope with PD and SWP soils that have outlet.(in other words depression don’t check) 2. Conservation Tillage- all cropland >2% slope 3. Terraces- all cropland 2-8% slope 4. Grassed Waterways- all cropland >2% slope 5. Contour Farming- all cropland >2% slope 6. Strip Cropping- all cropland >2% slope 7. Filter Strips- all cropland 8. Cover Crops- all cropland >2% slope 9. Lime and fertilize- always check unless class VII.

Homesite GoodFairPoor DrainageWDMWDSWP and PD FloodingUpland or Footslope Never CheckDepression or Floodplain Depth>60in deep40-60in deep<40in deep Slope<12% slope12-20% slope>20% slope Percolation Rate No bedrock, Clay, or Pan Clay or Pan <7in thick Clay or Pan >7in thick Shrink-SwellCracks less than 2in wide Never CheckCracks more than 2in wide

Over all analysis for Homesite Check according to the worst factor that you checked on each individual homesite factor. Example: Drainage- Good Flooding- Good Depth- Good Slope- Fair Percolation Rate-Good Shrink Swell-Good Overall analysis would be Fair