|
 Landscape
and Vegetated Buffers: Why Should I Be Concerned?
The removal
of trees, shrubs and other protective vegetation to make room for the
development of roads and houses has increased the amount of impervious area
in the lakeside landscape. Native vegetation with its deep root systems and
natural duff layer act like a sponge to hold storm water runoff and
associated nutrients. Impervious surfaces result in more storm water running
directly into the lake. Storm water runoff picks up non point source (NPS)
pollutants like soil sediment, nutrients and chemicals that can be
detrimental to lake water quality. NPS pollution that enters lakes affects
the nutrient balance of the water and creates a bottom habitat ideal for
weeds to root. It can cover fish eggs and habitat as well. Revegetate or
allow native landscape plants to fill in the shoreland zone and you will
increase biodiversity, increase wildlife habitat and protect your property
values.
What is a Buffer?
A buffer is an area of land
between developed property and the lakeshore where trees, shrubs and
ground cover plants are allowed to become established, or are manually
vegetated with appropriate (preferably native) plants. The best or ideal
buffer for ecological and water quality value is a combination of tall
trees, shrubs, groundcovers and duff. Lawn grass alone can not protect
the lake and associated shoreline. Grass roots are shallow and are
unable to filter out sediment and NPS pollution during rainstorms. While
a well-maintained lawn may be a wonderful asset to your property, a
buffer between the lawn and the water’s edge is essential to remove
nutrients and slow down storm water runoff before it reaches the lake.
Components of a Good Buffer
Trees
This upper canopy intercepts
raindrops. By breaking the fall of these tiny water bombs soil erosion is
reduced. Trees provide shoreline habitat for wildlife, shade for your house
and keep the water cool. Their deep roots take hold of the soil protecting
it from erosion and slumping. Lower tree branches can be trimmed for people
who prefer to have an unobstructed view of the lake, but the more tree
branches the better.
Shrubs
The second obstacle raindrops hit
on the way to the ground is shrubs. Shrubs provide wind protection and birds
love to take refuge in them. Their roots also hold the soil in place. Shrubs
are a great noise barrier and are low growing so they will not obstruct a
view of the lake.
Groundcovers
Vines, grasses and
flowers slow down surface water runoff and absorb nutrients and other
non-point source pollution. Their roots hold onto surface sediments.
Groundcovers that flower can create accents of color with a variety of green
backdrops. They also provide habitat for such insects as butterflies and
honeybees.
Duff Layer
Allow vegetation and woody
material to stay where it falls. Accumulation of plant matter on the ground
acts like a sponge, absorbs water, traps sediment and prevents erosion. Duff
hosts microorganisms that improve soil by breaking down and recycling plant
material into nutrients to be used in the growth of new plants.
Types of Buffers
A Natural Buffer
If you would
rather be fishing and swimming in the lake instead of maintaining a lawn and
landscape plants, than this method is the one for you. A naturally vegetated
buffer is the simplest and least expensive landscaping option for your lakeside
home. Decide where and how large an area you want as a buffer and then just stop
mowing. Plants will establish themselves in succession. First, grasses and other
groundcovers will grow. Then, as a duff layer becomes established (to allow duff
to accumulate, do not rake the area) the soil conditions will be suitable for
woody plants to grow. These native plants will be resistant to local pests,
(which lessens the need for chemical pesticides), and they will be adapted to
the climate (requiring less watering and protection from the elements).
Landscaped Buffer
If you prefer
a more managed and structured look you can create a landscape design for
your buffer. This means it will take less time to establish this protective
strip of vegetation, but more effort and money will be required. You can
still choose native plants for your buffer. Ask your local plant nursery
what native, local plants they propagate, and which will require the least
amount of fertilizer to be beautiful. University of Maine
Cooperative Extension has produced two wonderful, informative
brochures for planting with native plants:
Native Plants: A 2002 Maine Source List, which
provides a list of Maine nursuries and garden centers that sell native
plants, and
Gardening to Conserve Maine's Native Landscape: Plants to Use and Plants to
Avoid, which lists what plants are harmful to the
Maine landscape as well as a list of native plants with recommendations on
successful growing. Or you can, of
course, combine the two methods; for example,
allow some trees that are already established to grow and purchase some
flowering shrubs to plant along the shore, securing it from erosion.
Lake Access
Another very IMPORTANT aspect of a
good vegetated buffer is lake access. A winding footpath to the water helps
shed runoff into the vegetation. Often times a straight path will act like a
streambed, directing rooftop runoff right into the lake. Secure the walkway
to prevent erosion with mulch, rock, groundcover plants or other materials.
A beautiful touch for your access path is to edge it with plants like day
lilies (if in the sun) or hostas (if in the shade). These plants have great
root systems that will firmly hold the soil in place; they also fill in
nicely.
Fertilizer
Fertilizer use can be another hazard to your lake. By reducing the amount of
nutrients reaching the lake you can reduce the possibility of weed and algae
growth in the lake. Fertilizer will feed plants in the lake just as it does
on land. If the fertilizer you use for your buffer is applied before a large
rain event, much of it may end up in the lake. Be mindful of when you apply
fertilizer, if you use any at all. Also, stay away from using
phosphorus-containing fertilizer in close proximity to the lake.
Phosphorus is the middle number on a standard bag of fertilizer (10-5-2) and
it is what lake plants use to thrive. Zero phosphorus fertilizers are
available at many agriculture and hardware stores.
The best way to find out what your soil has to
offer your buffer plants, is to do a soil test. Soil testing kits are
available at your University
of Maine Cooperative Extension county office
or online at Analytical
Laboratory and Maine Soil Testing Service. You will receive an analysis
of the pH and nutrients in the soil sample. They will also send you
recommendations stating what you need to add to the soil to create a healthy
vegetated buffer.
What To Do Next...
You need a plan for your new or improved landscape. Make a sketch of the area
you want converted to a buffer. Review the University of Maine Cooperative
Extension factsheet "Designing
your Landscape for Maine." Ask your town Code
Enforcement Officer if you need any permits for the work you are going to be
doing. Take a soil sample to find out what nutrients are available. And
start planting!
Other Considerations
Install gutters and downspouts to catch stormwater runoff from your roof. If
roof runoff is allowed to fall from 30 feet up, soil erosion will occur around
the edge of your house. Water will also be more likely to be a problem under the
house if you don’t direct it away. Collect the water in a barrel and use it to
water your buffer, garden or lawn during dry days. If you have a good vegetated
buffer, you can point the downspout to drain directly into the buffer area.
Take the Buffer
Self-Assessment.
Lake*A*Syst |
Last
Modified:
05/30/08
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