DIY Chemical Applications
There are a few
basics that will be used in all chemical applications. Let’s
start with equipment. You should have a spray wand with an
adjustable spray tip that easily goes from a straight stream to
an open cone or fan pattern. Fan patterns offer better coverage
but have a limited range and are very prone to drift. The mist
created from an open pattern, the drift, can easily be windblown
onto non target species. Temperature inversions can even carry
drift away from the treatment area. Pressure is another
contributing factor to drift, high pressure creates more drift.
The straight stream covers the greatest distance with the least
amount of drift but is inadequate for close quarter
applications. Having a spray wand that is easily adjustable is
essential so that a combination of spray patterns can be used to
cover all scenarios. I will commonly start my application near
the boat with a moderately open pattern and as I work away from
the boat I will gradually shift to a closed pattern. This gives
the coverage needed at close range and then the straight stream
give you the distance, the combination allows you to cover a
larger area in a single pass by.
In this video you see how regular pond water runs and flows over
the surface of a leaf of American Water Lotus. It flows as if it
were liquid mercury, in beads of liquid but never penetrates the
plants surface and never saturates the plant. This is due to the
surface tension created by tiny hairs, a defense mechanism of the
plant. Without the proper surfactant your product will never come
into direct contact with the plants surface and therefore can't be
Green Algae Control's spray boat uses a custom injection system,
pictured right. With this rig we are able to inject the approiate amount
of product directly into our prop-wash where it is then quickly and
evenly distributed. This ensures uniform chemical concentrations over
the entire treatment area, which is essential to provide the desired
results. Other methods use drop tubes and various other methods. These
can be effective but are prone to collecting vegetation and debris and
then rising to the surface. This fixed sytem eliminates that.
Pictured Left: Straight stream, Moderate Fan, and Open Fan Patterns are
used to cover many different spaying scenarios.
Surfactants are especially important in topical treatments. A surfactant
improves coverage and increases chemical absorption. However not all
surfactants are the same. Some surfactants have Oil based components
that help resist evaporation and other Non-ionic surfactants can help
reduce surface tension and allow penetration of fine hairs. When
treating plants such as American Water Lotus and Water Lettuce the use
of a Non-ionic Organo-Silicone surfactant is critical to penetrate the
fine hair-like structures that repel water. Without this type of
surfactant the fine hairs create surface tension that causes the product
to bead-up on the hairs and roll off of the plant. On the other hand
some products like Imazamox based chemicals specifically say to use with
MSO type surfactants. MSO stands for Methylated Seed Oils, these
surfactants help penetrate fine hairs but also resist evaporation.
Chemicals are only absorbed through the leaves while in a liquid state;
this is why delayed evaporation is an important trait in a surfactant.
For the treatment of submerged vegetation you will need to inject
the chemical below the water surface. The injection of the product
will bring it into direct contact with the submerged plants and make
it more effective. If this product were simply applied topically
surface tension will hold the product on or near the ponds surface
where it is prone to drifting away from the treatment area via wind
and water currents. Injection can be done with nearly any spary
equipment so long as the spraying apparatus is atleast 8-10 inches
below the surface. Through years of experience and research we have
an Injection method that is far superier to any that we have seen
Hopefully this section will have given you an inside
look into what it means to propperly apply herbicides. With the
multitude of different plants you may encounter there is always an
appropiate application method to ensure the desired results. Effective
applications can be the difference between a sucessful treatment and
marginal results, it's cheaper to do it right the first time. GAC is
also offering, free of charge, the following paper that goes into
greater detail about the specficics of certain treatments and methods.
You are welcome to use this information to manaage your private pond.
Keep in mind though that YOU MUST follow all safety requirements and always comply with state and
federal laws. Fully read and understand all product labels and MSDS.