We understand that K-State hosted the National Collegiate Soils Contest in Spring 2016 and the NACTA Contest in Spring 2017. Will some of the same sites be used?
Yes, K-State hosted the National Collegiate Soils Contest sponsored by the American Society of Agronomy/Soil Science Society of America in April 2016 and the NACTA Contest in April 2017. The websites used for these contests are still open:
You are welcome to use any materials available at these websites. Some of the practice sites will be the same locations used for practice sites at these two contests. Other practice sites will be different. We will not be using the locations for the contest sites from the 2016 or 2017 contests. By the way, some of the FAQs from these contests are recycled for the 2018 Regional Contest. The answers have been modified in some cases because of differences in the handbooks and scorecards.
In the Parent Material section of the Handbook, how do we tell the difference between Eolian Sand/Eolian Loam and Loess?
The Parent Material section of the Handbook provides a good description of the characteristics that will be used to differentiate these parent materials. I would add that the loess in the contest area tends to have <25% sand, approximately. The % sand in eolian sand/eolian loam is quite a bit higher.
RMF Conc. box on the scorecard: This includes what in the old days we would call high chroma mottles, right?
Judgers should check Y in the box for RMF Conc. if pedogenic accumulations of Fe and Mn occur. Such accumulations would include what would be called high chroma mottles in the old days. However, it would also include Fe and Mn nodules and concentrations and pore linings of Fe and Mn.
RMF Depl box on the scorecard: This includes what in the old days we would call low chroma mottles, from poor drainage, right?
Judgers should check Y in the box for RMF Depl. when zones of chroma 2 or less and normally values of 4 or more are present when either Fe-Mn oxides alone or Fe-Mn oxides and clays have been removed by eluviation. This does not exactly fit what we would have called low chroma mottles in the old days.
The rules appear to read that a soil which has a depleted or gleyed matrix would not automatically have RMF Depl. checked “Y”, even though the entire matrix is depleted? Instead, we will only answer “Y” for depletions if there are other depleted zones/areas in addition to the depleted/gleyed matrix. Is that correct? This seems insane to me since a depleted matrix is obviously a depletion (and a big one at that).
The key issue here is for judgers to determine whether a soil horizon with a color for example of 10YR4/2 is in fact a depleted matrix. We have some very dark colored soils on floodplains and terraces where the value is ≤ 4 and the chroma is ≤ 2, i.e., mollic colors to a depth of 150 cm or more. Unless redox concentrations were present, we would not consider this as a depleted matrix, and we would not check “Y” on the scorecard for RMF-Depl. If redox concentrations were present, “Y” should be marked for both RMF-Conc. and RMF-Depl. The official judges will not make automatic decisions in regard to linking RMF-Conc., RMF-Depl., and a “g” designation. Instead, they will be consistent in the way they make decisions. For example, they will make two separate decisions in assigning a “g” designation and indicating a Y” for RMF-Depl.
Would you say that the occurrence of depletions that are not related to a seasonally high water table are common in the contest area?
Relict depletions are not common in the contest area. The official judges will associate depletions with a chroma of 2 or less with a seasonally high water table. The presence of these depletions will affect the soil wetness class. Judgers need to be careful not to confuse carbonate concentrations with depletions.
Is a blank box on the scorecard counted the same as “none,” “no,” or “-“?
We want this to be a positive educational experience for all participants. We will try to avoid enforcing rules that could be considered as “picky” rules. We have indicated in those sections of the handbook where we would prefer a “no”, “none”, and/or “-“ response for a box on the scorecard. Hence, there may be some differences as to what we prefer for a negative response in different sections of the scorecard. In my opinion, a blank is a negative response, although it might not be the response that we would prefer. As long as the answer is not ambiguous, we will give the judger the benefit of the doubt and will count “N”, “no”, “none”, “-“, or a blank box correct.
Can you explain a little more background on "clayey sediments" being listed as a parent material in some of the soil surveys in the area?
The term “clayey sediments” is sometimes used in older soil survey reports from the Bluestem Hills in association with paleosols when the exact parent material source of the sediments was not known. We will not use this term during the contest.
Can you give an explanation of where you expect footslope to be used as a landform?
In the Bluestem Hills, we sometimes have a prominent, elongated footslope at the base of a hillslope. This landform will be shown at one or more practice sites. These elongated footslopes may have formed due to solifluction under periglacial conditions during the Late Wisconsin. Colluvium/pedisediment will be the parent material for this landform. Unless a situation develops that we do not anticipate, the selection of footslope as a landform will accompany the selection of footslope as a hillslope profile position.
When assessing soil limitations for septic tank effluent treatment areas, the first of the criteria is average hydraulic conductivity between 45 and 180 cm. How do you average two (or more) HC classes?
To simplify, we have decided to base the determination on the most restrictive layer between 45 and 180 cm. If an R or Cr occurs within that depth, the hydraulic conductivity would be very low. For the practice sites, the judges will write a note for the reason for the suitability rating.
For the criteria for Evaluating Soil Limitations for Dwellings Without Basements, how would an average for rocks > 7.5 cm in diameter be determined? Also, I assume you do not go below a bedrock contact?
If necessary, we will calculate the weighted-average content of rocks > 7.5 cm in diameter from the soil surface to a depth of 100 cm. If an R or Cr horizon occurred at a depth < 100 cm, we would make the calculation to the top of the R or Cr horizon. Please note that in most cases, the occurrence of an R or Cr at a depth < 100 cm would cause a more restrictive limitation than that caused by the rock content.
For Dwellings without Basements, what is the limitation being referred to in the criteria “Texture of most limiting horizon”? Is it the most limiting for subsurface hydraulic conductivity, or does it refer to the texture of any horizon that occurs within the 25-100cm depth range?
It refers to the texture of any horizon that occurs with the depth range of 25 to 100 cm.
For the criteria for Evaluating Soil Limitations for Septic Tank Effluent Treatment Areas, how is the coarse fragment content in the 45 – 105 cm depth evaluated?
If necessary, the weighted average content of coarse fragments from 45 – 105 cm would be used.
In regard to the Official Series Description for Wymore, there are redox concentrations in the Bt2 (43 – 64 cm) horizon and in horizons below. The matrix color of the Bt2 is 10YR 4/2. Would it be considered to have aquic conditions within 50 cm? Wymore is also listed as moderately well drained. Do the redox concentrations allow us to interpret the colors (value of 4 or more and chroma 2 or less) as redox depletions?
Most of the soils in the contest area that are mapped as Wymore would be better drained than the soil at the type location for Wymore. Typically, the soils mapped as Wymore in the contest area will have a matrix chroma ≥ 3 in the upper part of the Bt and to a depth of at least 50 cm. In addition, for this contest, we would not interpret the morphology of the soil at the type location to have aquic conditions. Please note that this soil has dark colors due to the organic matter content. We would not interpret the chroma 2 matrix color in the Bt2 horizon as redox depletions. Typically, the Wymore soils that occur in the contest area will exhibit either a chroma 3 matrix or else with a chroma 2 matrix without RMF concentrations in the upper part of the Bt. The official judges will assign Wetness Class 3 for such soils.
If a site occurred within a drainageway, what would be the Hillslope Profile Position?
To answer this question, we need to consider first how we are interpreting the landform for a drainageway. We do have landforms in the contest area that could be described as upland drainageways. This landform would occur along a small, intermittent stream. We considered putting an additional landform on the scorecard for this landform that would have been listed as “upland drainageway.” However, we thought it would add too much complexity for the judgers, and we would have difficulty explaining to them how this landform would be separated from a small floodplain. In addition, we have upland drainageways in the contest area where a very small stream valley is filled with colluvium without a noticeable floodplain. For the landform where a small floodplain with alluvium occurs, judgers should check Floodplain as the landform. If the small valley is filled with colluvium without a noticeable floodplain, Footslope should be checked for the landform. Now, to get to the question of Hillslope Profile Position for the upland drainageways in the contest area. If Floodplain is checked for the landform, the Hillslope Profile Position will be Toeslope. If Footslope is checked for the landform, the Hillslope Profile Position will be Footslope. The upland drainageways in the contest area will not have a floodplain that would be extensive enough to select None (gradient <2%) for the Hillslope Profile Position.
In the bottom of an upland depression, will the Hillslope Profile Position be Toeslope or None (gradient <2%)?
The depressions that occur in the contest area tend to be small and are often filled with colluvium. To avoid controversy, we will give credit for either Toeslope or Footslope for the bottom of these small depressions. The bottoms are not of large enough extent to select None (gradient <2%). It is also possible for these upland depressions to have a backslope and a footslope component along the hillslope grading into the depression.
If Stream Terrace is checked for the Landform, do we mark None (gradient <2%) even if the Hillslope Profile Position is a summit (slopes down on all sides of the terrace)?
Most of the terraces that occur in the contest area are well defined and will be extensive enough to select None (gradient <2%). If the terrace has limited extent with a slope >2%, the Hillslope Profile Position that is the most appropriate should be checked.
Will the students be told if the site floods, and will a frequency be given? Or will it be obvious?
If a site is subject to occasional or frequent flooding, we will provide that information. Otherwise, the students should assume that a site is not subject to flooding.
Can your low terraces flood?
Yes, we have low terraces that are subject to occasional flooding.
Regarding Table 10, it is specified in several places that hydraulic conductivity class is influenced by the organic matter content of the soil, referencing "high" or "moderate" or "low" organic matter content. However, the thresholds for these three classes are not specified. Similarly, the Moderately Low HC class refers to "high clay content" but does not specify how much clay is considered "high". Would it be more appropriate to use specific class limits based on organic carbon and clay contents?
These descriptions are meant to be general enough to be used for a wide range of soil properties. We think it is a better learning experience for students if they see how the official judges handle these situations. Then, they can use their best judgement and make their own interpretations about organic matter and clay contents. We do not want to define arbitrary class limits based on organic carbon and clay contents. However, we will add site notes for the practice sites explaining the reasons when the official judges make adjustments in the hydraulic conductivity class because of clay or organic matter contents or shrink-swell potential.
Regarding the description of Table 11, it is stated that "If the profile is not visible to a depth of 150 cm, or if you are requested to describe a soil only to a shallower depth, then you may assume that the conditions present in the last horizon described extend to 150 cm." While it would be highly unlikely, what if the pit is 160 cm deep, the depth of description is 110 cm, and there is observable bedrock at 130 cm? Would the visible root restrictive layer be ignored because it is below the depth of description?
For the scenario mentioned above, we would have made sure that the depth of description included the observable bedrock. For example, we would have given the profile depth as 135 cm (not 110 cm), and we would instruct the pit monitor to make sure that all judgers could see that bedrock was exposed within the profile depth. We should also mention that the depth to bedrock can be quite variable within the pit. In addition, there can be much variation between depth to bedrock from one control section to the other. We will make sure that each profile has the same number of horizons to describe so that each profile has the same number of points possible. Judgers should take the depth measurements from the tape measure anchored to the pit face within the control area.
If redox concentrations are present, would they be identified as such and also recognized as Fe-Mn matrix concentrations?
Redox concentrations would be recognized with a Y in the RMF Conc. column and with an FE-MN in the Matrix Conc. column.
I am assuming that marking a Y for RMF Concentrations does not automatically require listing FE-MN under Matrix Concentrations?
No, this is not our intent. If a Y is marked for RMF, the type of Matrix Concentration must also be given. Soils occur in the contest area that have multiple Matrix Concentrations in the same horizon. For example, we have soil horizons where Fe-Mn matrix accumulations occur with calcium carbonate accumulations. In this case, Y should be marked for RMF, and FE-MN and K should be marked under Matrix Concentration. 1 point would be awarded for the FE-MN and 1 point for the K.
Is there ever a time when you would put a k, y, or z on the horizon name but not list them under Matrix Concentrations?
We intend for the students to make two separate decisions in regard to the horizon suffix symbol k, y, or z and the type of Matrix Concentration. In our professional work, those two decisions are not linked. For example, it is possible to have a horizon with disseminated pedogenic carbonate in which the Bk designation should be used. However, the disseminated carbonate would not be considered as a concentration of pedogenic carbonate that occurs in the matrix. Also, coatings of pedogenic carbonate can occur along peds. These features are ped coatings and not concentrations occurring in the matrix. It is up to the coaches to decide how they want to teach this to students. If coaches teach their students to link them, this would be correct most of the time for the soils in the contest area. However, these two decisions will be made separately and not linked by the official judges.
Is there ever a time when you would mark Y for redox concentrations but not put FE-MN under Matrix Concentrations?
We also intend for the students to make two separate decisions in regard to marking a Y (yes) for RMF concentrations and for marking FE-MN as a Matrix Concentration. Please note that RMF concentrations can include pore linings or ped coatings of Fe and/or Mn. These features are coatings (cutans) and not concentrations that occur in the matrix. In this case, if no other forms of RMF concentrations were present, we would mark Y for RMF concentrations and mark a "-" for matrix concentrations. Again, coaches can decide how to teach this to their students. If coaches teach their students to link these two decisions, this would give the correct answer most of the time for the soils in the contest area. However, the official judges will make two separate decisions.
What is your interpretation on carbonate 'masses', do you consider them significant for pedogenesis (B vs C horizon nomenclature)?
We generally do not have carbonate masses in the contest area. The carbonate forms in the contest area typically include nodules, ped coatings, and/or filaments (which are probably ped coatings). We believe these forms are pedogenic. The soils exhibiting these features in the contest area usually have soil structure. We generally would describe these horizons as some type of a Bk such as a Btk, Bkss, Bk, etc. Also, we do have Cr horizons with pedogenic carbonate forms. These will be described as Crk or Crtk.
How common is gypsum accumulation in this area? Are there series that have "y" suffixes mapped in the area? (I didn’t find any in the OSD's).
We didn’t recognize gypsum accumulation in the contest area until we started soil micromorphology for research projects. Gypsum tends to occur in association with pedogenic carbonate in soils in the contest area that also have elevated Na contents. It is difficult to recognize the gypsum in field examination, except it occurs as white accumulations that do not react with 10% HCl. Gypsum commonly occurs in soils with a parent material sequence of loess over colluvium over residuum. Dwight and Konza often contain gypsum accumulations. We have posted a guidebook for a field trip to the Rannells Prairie on the website for the 2016 National Contest. The Konza pedon in the guidebook contains gypsum, and the horizon nomenclature includes a y suffix. We will post % gypsum for any soil horizon where gypsum occurs and if the gypsum content is needed for classification purposes.
"k" horizons seem pretty common, but according to the NRCS OSD site, there are no Calciustolls or Calciudolls mapped in the contest area. What part of the "calcic" definition in the Taxonomy is usually NOT met in these Bk's (>15% CCE or one of the following: >5% more CaCO3 compared to C horizon, OR >5% pedogenic carbonates)? (for example: Benefield).
We will post CCE for soils where the data are needed for classification. In most cases, the soils in the contest area, which have a k designation, will not have the 15% CCE required for a calcic horizon. Many of the soils in the contest area will have >5% pedogenic carbonate accumulations. Hence, we use a k designation, but the classification for a calcic is not met. We could find inclusions in a mapping unit of a soil like Clime that could make the criteria to classify with a calcic horizon.
There are a few redundancies on the scorecard. For example, marking a “k” under horizon subscript and then marking “K” under Matrix Concentrations while using the same criteria. What is the meaning for this?
We do not view this as a redundancy because these are separate determinations. The horizon subscript k should be used when appropriate according to the definition found in Chapter 18 of the 2014 Keys to Soil Taxonomy. K should be marked as a Matrix Concentration whenever matrix accumulations of calcium carbonate occurs. Please note to follow this same procedure for a y horizon subscript and a Y matrix accumulation of gypsum. We have soil horizons in the contest area that may have matrix accumulations of both calcium carbonate and gypsum.
Many BC horizons underneath argillics would qualify as cambics, but there is no point in recognizing them. Also, we may find a Bw horizon that qualifies for cambic above a Bk horizon that qualifies for calcic. Should we mark cambic if it is not the diagnostic horizon that determines class placement?
Although it is open to interpretation, the intent of Keys to Soil Taxonomy is probably to not recognize a cambic if it occurs above or below another diagnostic horizon. For this contest, we will not mark cambic if a horizon with cambic properties occurs above or below an argillic or calcic horizon.
Are the disseminated carbonates in the contest area visible with a hand lens?
Yes, disseminated carbonates in the contest area are visible with a hand lens.
If a Cr horizon is cemented by finely disseminated carbonates, with no visible coatings or masses in the horizon, are those carbonates considered pedogenic?
In the contest area, the Cr (or Crk) horizons that contain carbonates will exhibit carbonate nodules, masses, and threads (films) of carbonate between mudstone layers that are clearly visible. At least one practice pit will provide an excellent example of pedogenic carbonate forms that occur in Crk horizons in the contest area. Most of the Cr horizons in the contest area have clearly visible pedogenic carbonate forms such as nodules, masses, and threads. Such horizons will be designated Crk. Although rare, Cr horizons can occur in the contest area that lack visible forms of pedogenic carbonate. We will designate such horizons as Cr.
The handbook says that if a soil has measureable gypsum content, that data will be given. But for carbonates, it will be given only if needed for classification. Could there be a soil where there are detectible or visible carbonates but where no lab data will be given?
If a soil horizon has measureable gypsum content, we will provide % gyspum because of the difficulty in identifying the gypsum and distinguishing it from pedogenic carbonate. Some soil horizons in the contest area will have pedogenic carbonates, but the soil matrix is non-calcareous, and the quantity of pedogenic carbonate is low enough so that it is obvious that the CCE is less than 15%. CCE data will be given only if the official judges believe that the data are needed for classification.
If lab data reveals any measureable content of gypsum or carbonates or sodium in an A or B horizon, is that enough to warrant use of the lowercase letters for naming the horizon?
Since gypsum will be difficult for the judgers to identify and separate from pedogenic carbonate accumulations, we will designate any horizon in which the gypsum content is reported with the suffix y. We tend to put a k on any horizon with visible pedogenic carbonate. Many soils in the contest area will have measureable amounts of Na. We will provide SAR data only if needed for soil classification. We tend not to use the n suffix unless the SAR is approaching 13, and the soil morphology is typical for a natric horizon.
In the recognition of soluble salts as a matrix concentration, the text refers to the use of lab data for identification. Is EC >4 ds/m a good reference point to give the students?
Yes, we will not mark Z unless the EC meets that threshold.
Diagnostic subsurface horizons and features: Regards to albic horizons and albic materials, I am assuming if “albic horizon” is checked then “albic materials” must also be checked. However, “albic materials” might be used independently if they are <85% of the horizon?
This is correct.
Can you give us more details about when “Lithological discontinuities” would be checked as a diagnostic feature?
The judges will check Lithological Discontinuities when a prefix 2 is used in the horizon nomenclature. Please note that many soils in the contest area have multiple parent materials or multiple ages of the same parent material, e.g., two ages of colluvium.
Do Vertisols occur in the contest area?
We have soils in the contest area that will classify as Vertisols. If needed for classification, we will provide information on the data sheet for the cracking characteristics of any soil that is close to meeting the classification criteria for a Vertisol.
Do you recognize Cd horizons in the contest area?
We have Permian mudstones and shales in the contest area that have traditionally been described with a Cr designation, sometimes with the addition of suffix k and/or t (Yes, we can have Crkt). Some people have suggested that our Cr horizons should be designated Cd horizons because some of the material will mostly slake in water, although it could take several days of soaking. Our experience is that these mudstones and shales are partly cemented with carbonates. When you see these materials in the field, we are curious about your opinion and whether you would designate them as Cr or Cd. A task force committee is currently working within the National Cooperative Soil Survey to refine the definitions for Cr and Cd horizons and paralithic versus densic contacts. From a practical standpoint, this is not a big deal anyway because paralithic and densic contacts are both root limiting layers. For this contest, we decided to make this an easy decision. We will not use the suffix d on the contest, and densic contact is not on the scorecard.
Is there are reason that Epiaquents are not included in the key?
Epiaquents do not occur in the contest area, and we ran out of room to add additional great groups.