Field Survey & Data Collection Flashcards

In a 'problematic' wetland situation where hydric soils and hydrophytic vegetation are present but hydrology indicators are absent, a delineator should:

Answer: Investigate further using soil morphology, landscape position, and regional hydrogeomorphic data

When one of the three parameters is not clearly met, the delineator must apply professional judgment using additional evidence such as soil morphology, topographic position, and known hydrology patterns before reaching a determination.

When flagging a wetland boundary in the field, survey flags are placed:

Answer: Along the line where the transition from positive to negative parameter indicators occurs

Wetland boundary flags mark the precise location where field indicators transition from meeting all three wetland criteria (wetland side) to failing one or more criteria (upland side).

The 'atypical situation' exemption in the Corps of Engineers methodology applies when:

Answer: Human activities or natural disturbance events have recently altered the normal expression of one or more parameters

Atypical situations occur when recent disturbances (e.g., draining, filling, fire, drought) suppress the normal expression of wetland indicators, requiring the delineator to assess what conditions would exist without the disturbance.

On the Corps of Engineers Wetland Determination Data Form, the 'Dominance Test Worksheet' is used to:

Answer: Determine whether dominant plant species support a positive hydrophytic vegetation indicator

The Dominance Test Worksheet tallies dominant species by NWI status to determine whether more than 50% of dominants are hydrophytes, which is the key calculation for the vegetation parameter.

A 'Routine Determination' under the Corps of Engineers methodology is most appropriate when:

Answer: Typical indicators are clearly present and site conditions fit standard, undisturbed conditions

Routine Determinations are used for sites with clearly present, unambiguous wetland indicators that do not require the detailed sampling effort of a Comprehensive Determination.

To precisely locate a wetland boundary between a forested wetland and an adjacent upland, the recommended field approach is to:

Answer: Move incrementally from the wetland toward the upland, placing flags where parameters transition from positive to negative

The standard practice is to begin in clearly positive wetland conditions and move toward the upland, placing sample points at intervals until all three parameters are no longer met, then flagging that transition line.

Which document must a delineator consult to identify the applicable hydric soil and hydrology indicators for a specific geographic region of the United States?

Answer: The applicable Corps of Engineers Regional Supplement to the 1987 Wetland Delineation Manual

Regional Supplements update the 1987 Manual with region-specific hydric soil indicators, hydrology thresholds, and problematic wetland guidance calibrated to local climate, soils, and plant communities.