Land Judging Lecture Notes Flashcards

Vocabulary definitions for land judging, including soil texture identification, drainage classes, slope rating, AWHC calculations, land classification rules, and homesite suitability criteria.

Coarse Texture (Surface or Subsoil)

No Ribbon, No Ball

Medium Texture (Surface or Subsoil)

Less Than $2''$ Ribbon

Fine Texture (Surface or Subsoil)

Over $2''$ Ribbon (Sticky, Shiny)

Fragipan

A dense layer of medium textured soil compacted soil

BedRock

A layer of rock found under the ground that conventional machinery cannot move.

Rock Outcrop

A mass of rocks found on the top of the ground that can't be moved by conventional machinery, something that you must go around when working

Rock Outcrops (None or Few)

$>200\text{ feet}$ apart; or $0-50\text{ square feet}$ per acre

Rock Outcrops (Common)

$100-200\text{ feet}$ apart, or $50-900\text{ square feet}$ per acre

Rock Outcrops (Many)

$<100\text{ feet}$ apart or $> 900\text{ square feet}$ per acre; more than $5$ outcrops

Excessively Drained

Coarse texture in the subsoil that extends to $36''$ or to bedrock; many rock fragments

Well-Drained

No gray Mottles present in the top $36''$

Moderately Well-Drained

No gray mottles in the top $17''$ but any amount below $17''$

Somewhat Poorly Drained

There will be up to 50% gray in $7''$ to $17''$

Poorly Drained

There will be over $50$% gray in $7''$ to $17''$ or any amount in the top $7''$

Rock Fragments

Any rock larger than sand that can be moved by hand

Rock Fragments (None or Few)

$0\%$ to $15\%$

Rock Fragments (Common)

15% to 35%

Rock Fragments (Many)

Over 35 %

Available Water Holding Capacity (High)

$6.0$ or higher

Available Water Holding Capacity (Medium)

$$4.0-5.99$$

Available Water Holding Capacity (Low)

Less than $4.0$

AWHC Equation (1 Texture)

$$\text{depth of soil} \times \text{texture coefficient}$$

AWHC Equation (2 Textures)

$$(\text{depth of surface soil texture} \times \text{coefficient}) + (\text{depth of subsoil texture} \times \text{coefficient})$$

Texture Coefficients

Coarse ($0.05$), Medium ($.20$), Fine ($.15$)

Slope

The amount of rise from one point to another point

Slope A

0-2%

Slope B

2-5%

Slope C

5-12%

Slope D

12-20%

Slope E

20-30%

Slope F

> 30\text{%}

Erosion

The wearing away of the topsoil by wind or water

Erosion (None to slight)

Over $5''$ of topsoil present

Erosion (Moderate)

$3''-5''$ of topsoil present

Erosion (Severe)

Less than $3''$ of topsoil present

Land Class 5

ONLY poorly-drained floodplain or poorly-drained depression

Land Class 7

Suitable only for TREES; occurs on slopes more than 30%

Moderately Deep Soil

Soil to bedrock ($20''-36''$) or less than $24''$ to large structure-less clay; ADD one land class

Shallow Soil

Soil to bedrock ($10''-20''$); ADD two classes

Filter Strips

Recommended practice for all cropland (classes 1-4)

Potential Environmental Problems in Streams (High)

Cropland (Classes 1-4) with slopes more than 5%

Potential Environmental Problems in Groundwater (High)

Shallow or very shallow to bedrock

Suitability for Homesite (Poor Flooding)

Floodplain or Depression

Suitability for Homesite (Good Percolation Rate)

No fragipans

Suitability for Homesite (Poor Shrink-Swell)

Visible cracks in soil

Erosion (None to slight)

Over $5''$ of topsoil present.

Erosion (Moderate)

$3''-5''$ of topsoil present.

Erosion (Severe)

Less than $3''$ of topsoil present.

Land Class 5

ONLY poorly-drained floodplain or poorly-drained depression.

Land Class 7

Suitable only for TREES; occurs on slopes more than 30%.

Moderately Deep Soil

Soil to bedrock ($20''-36''$) or less than $24''$ to large structure-less clay; ADD one land class.

Shallow Soil

Soil to bedrock ($10''-20''$); ADD two classes.

Filter Strips

Recommended practice for all cropland (classes 1-4).

Potential Environmental Problems in Streams (High)

Cropland (Classes 1-4) with slopes more than 5%.

Potential Environmental Problems in Groundwater (High)

Shallow or very shallow to bedrock.

Suitability for Homesite (Poor Flooding)

Floodplain or Depression; likely to have poor drainage.

Suitability for Homesite (Good Percolation Rate)

No fragipans; indicates good drainage.

Suitability for Homesite (Poor Shrink-Swell)

Visible cracks in soil; related to poor drainage.

Suitability for Homesite (Slope Consideration)

Optimal slopes are generally less than 20%; slopes greater than 30% are not suitable.