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At the lower edge of Level Four, a scallop shaped
sharp edged rock with a relatively smooth top forms
the water stream into a shimmering spherical shape as
it falls over the edge. The smooth and
continuous flow causes very little turbulence as it
enters the small pool at the beginning of Level
Five. This level contains four terrestrial
environments. Pinewort - Hypericum drummondii
grows in a plug of decayed peat moss that absorbs
water from the eastern edge of the brink rock.
Below it, is an area of "stagnant" water
logged soil, with a group of unidentified miniature
ferns that grew volunteer in the kid's
"turtle" sandbox and have been moved to this
location. There is a moss covered rock sitting
on top of the gravel but in the water. Bugle
Weed Mint - Lycopus Virginicus, Woods Nettle - Laportea
canadensis and Viola macklowsyi? grow in
the moss on the rock. The mossy rock is
protected from the sun by the shade of these plants
and of scrub-willow branches, growing among the
wetlands plants at the edge of the pond.
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The primary purpose of Level Five is to condition the
flow of the water, so that the fall from this level to
the pool occurs as a ribbon smooth sheet of
water. Small flat pieces of broken and split
flagstone and limestone gravel pebbles are positioned
so as to evenly spread the water stream across the
brink of the ribbon falls. Unlike the other
falls, the ribbon falls does not have a rock edge
brink. Instead, the smooth plastic liner
material is left exposed here, allowing the water to
establish a low turbulence flow to an abrupt, thin,
flexible edge to generate a glassy ribbon
waterfall. The ribbon falls minimizes turbulence
in the pond while efficiently entraining air into the
pond water. This is important, because
turbulence negatively effects the growth of the hardy
water lilies growing in the pond. Rough water
will submerge the floating leaves and blossoms and
cause them to rot. I have found that the falls
requires occasional cleaning with a brush.
Otherwise, filament algae will spoil the appearance of
the ribbon.
The final level is the fish / lily pond. Water
hyacinth, Water Lettuce and Parrot's Feather, float on
or near the surface. The Parrots feather pokes
through openings and forms hedges in unoccupied shore
areas. Sedges and Scrub-willows border the pond
on all but the southern side. The non-disturbing
quality of the ribbon falls is evidenced by the mirror
smooth water surface and the presence of lily pads in
close proximity to the falls.
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Level Five
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