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Locating the Greenline. Define the greenline Sampling using a monitoring frame Greenline rules Examples. Defining the Greenline. The first perennial vegetation that forms a lineal grouping on or near the water’s edge. ( Winward 2000). Lineal Groups.
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Locating the Greenline • Define the greenline • Sampling using a monitoring frame • Greenline rules • Examples
Defining the Greenline The first perennial vegetation that forms a lineal grouping on or near the water’s edge. (Winward 2000) Lineal Groups
Greenline: The first lineal grouping of perennial vegetation, embedded rock, or anchored wood at least 20 cm X 50 cm (8” X 20”).(the length and width of one monitoring frame)
Using a Monitoring FrameAlign the frame perpendicular to the stream flow at the water’s edge and move until it meets the greenline. The frame may be rotated up to 75° from parallel to streamflow to meet greenline criteria.
Ten rules to ensure: Precision Repeatability Consistency Greenline Rules
Greenline Rule A The greenline can be comprised of any combination of perennial vegetation, shrub/tree seedlings, embedded rock, or anchored wood provided that there are no patches of bare ground, litter, or nonvascular plants greater than 10 cm by 10 cm within the plot.
Bare Ground: A single patch of bare ground exceeding 10 cm X 10 cm (about 4 inches squared).
Bare Ground: Non-vascular plants Non-vascular plants (mosses, lichens, etc.) are not part of the greenline.
Perennial Vegetation > 4” bare patch (not continuous) There must be at least 25 percent continuous, live foliar cover of perennial herbaceous vegetation and/or shrub/tree seedlings (< 0.5 m tall) within in the plot. …comprised of any combination of perennial vegetation, shrub/tree seedlings… NO
Cover equals the shadows cast if the sun was directly overhead. Perennial Vegetation >25% is shaded/covered, and bare patches do not exceed 4 inches – thus this is the greenline. YES
The greenline may include rocks at least 15 cm in diameter with no evidence of erosion behind them, talus Embedded Rocks slopes, and bedrock outside the active channel and above the scour line.
Anchored wood may include logs and root mats if they are above the scour line, not likely to move in high flows, and have no evidence of erosion behind them. Log (Wood) Anchored Wood Rock
Greenline ? No
Greenline Rule B If woody plants are located closer to the water’s edge than qualifying perennial vegetation, rock, or wood then the greenlineis located at the base of the shrubs or trees.
Greenline Rule B When trees and shrubs are present, there is canopy directly overhead, and there is no understory beneath the canopy… …the greenline is located by drawing a line connecting the base of the plants on the stream side.
Greenline Rule B When there is no canopy cover above the line joining the bases of woody species, the frame should be moved away from the stream until the greenline is reached or the distance from the stream is 6 m.
Greenline Rule B Plants rooted on the opposite side of the stream are not considered greenline
Greenline Rule C Exposed live shrub or tree roots are part of the greenline.
Greenline Rule D Avoid sampling when the greenline is flooded.
Greenline Rule E The edge of the water is the greenline when perennial plants grow in the margins of the stream.
Greenline Rule F When plants occupy the entire width of the channel, the greenline is down the deepest part of the channel.
Greenline Rule G Brookgrass (Catabrosiaaquatica) American Speedwell (Veronica Americana) Floating and submerged plants are not part of the greenline (unless rooted and above the water line).
Greenline Rule H Block detached from streambank Fracture Slump blocks detached from the bank are not part of the greenline. If vegetation covers the fracture, creating a new floodplain (false bank), the greenline is the edge of the vegetation along the stream.
Greenline Rule I Active Channel The greenline follows the outside channel on each side of an island and does not cross onto an island. Islands Islands: bound by water at low flow or by channels that are scoured frequently enough to prevent perennial plant growth.
Greenline Rule J The greenlineis absent if the greenline rules are not satisfied within 6 m from the water’s edge. Use edge of terrace or 1st bench for other indicators. More than 6 meters
Greenline Rule J If the waterlines of a meander are less than 6 m apart and the greenline rules cannot be satisfied, then “NG” is recorded and the frame is placed at the top of the peninsula to measure other indicators.
Greenline is absent at well-defined trails (livestock, hiking, etc.). Place frame on a line joining the greenline on either side of the trail. Greenline Rule J Well defined livestock trail
Where is the Greenline? 6 meters (20 ft) No Greenline (NG)
Where is the Greenline? Greenline The greenline may include non-hydrophilic species.
Where is the Greenline? Once the block re-attaches, it becomes part of greenline. This feature is a “false bank”