This follows the Oklahoma manual used at the national contest. States use different cards, and your contest's rules and judges decide.
How the key is worked out
Depth, slope and erosion become classes as on pages 3 and 4 of Land Judging in Oklahoma (4H.HPS.101). Permeability follows the subsoil and runoff the slope (page 5); set either by hand if your judges call it differently. Each factor has a best possible class (page 6), the field gets the worst, and Tables 1 to 5 can lower it further. Every table row is checked against this tool; a field outside the tables gets a note.
The opening fields are the 2006 National Land Judging Contest fields, and the key matches the official answers on every line. Field 1, shallow on a 3.8% slope, drops from III to IV.
Students can practice on random fields; coaches can grade a contest with team totals from the best three of four.
Questions from coaches and students
How do you find the land capability class?
Each factor has a best possible class: a 2% slope can be no better than Class II, a shallow soil no better than III. If only one factor keeps the field out of Class I, that factor sets the class. With two or more, the manual's tables give the answer, and some pairs lower it further.
What counts as a major factor?
Coarse surface texture, a shallow or very shallow soil, any slope over 1%, any erosion beyond none to slight, rapid or very slow permeability, and rapid or very slow runoff (except on rapidly permeable soil). Wetness and flooding count when the site card gives them. Mark 9 None only for Class I.
When do you mark terraces, 15 and 16?
On cultivated land, Classes I to IV, with more than 1% slope, unless the surface is coarse. Mark 16 only with 15. With overhead water you build a diversion terrace (17) and leave out 16.
Which soil test values need fertilizer?
Mark 21 when pH is 6.3 or less, or above 8.0. Mark 22 when phosphorus is under 60 lb per acre and 23 when potassium is under 300. Mark 24 when nitrogen is given as deficient. If none apply, mark 25.
How is a land judging card scored?
Each field is worth 75: 45 for Part I and 30 for the treatments, so 300 for four fields. There is no partial credit, major factors must be exactly right, and if a field needs three treatments only your first three marks count. Judges set the points for each item.
Does my state use this card?
Not always. This follows the Oklahoma manual used at the national contest in Oklahoma. Some states have their own system: Georgia's FFA guide uses different slope classes, a drainage item and its own lime rule. Use your contest's card and rules; the judges' key is final.
Which edition of the manual is this?
Land Judging in Oklahoma, 4H.HPS.101, revised by Jason Warren, dated December 2008 and posted as the 2009 manual. OSU's FFA and 4-H land judging pages say it "will be the authority for rules, placing, and grading", and OSU's 2025 contest packet calls it the most recent manual. The manual itself says it "shall be used to resolve contest differences".
Sources: Land Judging in Oklahoma, 4H.HPS.101 (PDF); OSU FFA Land Judging CDE; OSU 4-H land judging; OSU FFA land judging packet, 2025 (PDF); 2006 national contest fields; Georgia FFA Land Judging Contest Guide, June 2024 (PDF); Oklahoma Conservation Commission, national contest.