Chapter 3: Aquatic Vegetation Management Flashcards
True or false: the planned use of a body of water often determines the need for management or control of aquatic plants
True
Many _____ may be pests in some situations and desirable in others depending on their abundance, use of waters they inhibit, or personal values of people using or living near the water
Aquatic plants
The application of ____ and ____ to aquatic environment management offers the best solution for meeting the diverse interests of all water users.
Science and policy
Aquatic weeds are usually separated into four broad categories based on their life form: __, ___, ___, ____,
Algae
Emersed
Submersed
Floating vascular plants
True or false: the first step toward prevention or control of aquatic weeds is to correctly identify them
True. Most control methods are aimed at specific plants or groups of plants
____ are the most primitive plants in structure and organization. They are also the most common and uniformly disturbed.
Algae
____ are unicellular and capable of carrying out all life processes without specialized tissue such as leaves, roots, or stems.
Algae
Under conditions of ____ and phosphorus levels and during hot calm sunny weather, algae multiply rapidly.
High nitrogen
Algae accumulates in large masses called ___.
Blooms
The two types of algae are ____ and ___.
Filamentous and plankton
_____ algae consist of long stringy hair like filaments that form in mats or pond scums during summer. Can be seen in plain sight. Can also form a green fur like coating on stones.
Filamentous
____ algae are commonly single cell or small colonial groups. Each ounce of water can contain millions of microscopic algae. In large numbers, they can color the water. Upon death, they can release foul odors and release toxins.
Plankton
True or false: filamentous algae can release toxins upon death that could be toxic to humans and animals.
False. Plankton algae can.
True or false: vascular plants are less complex than algae in structure and organization.
False. They are more complex.
What type of plant has specialized tissues such as roots, leaves, stems, and flowers?
Vascular plants
____ plants could be annuals or perennials.
Vascular
What type of plant is rooted or anchored in the bottom soil but has most of the leaf-stem tissue above water?
Emersed plants
True or false: emersed plants parts above water rise and fall with the changes in water level.
False. The portion of the plant above water does not move. For example, cattails.
____ plants grow with all or most of the vegetative tissue below the water surface. They are either free floating or more often rooted to the bottom. Example: pondweed
Submersed
__ plants are either free floating or anchored to the bottom while most of the plants tissues are above water. Example: water lilly
Floating
Proper design of ___ and ___ are important factors in preventative weed control.
Ponds and ditches
For weed control is shallow water or steep banks more beneficial?
Steep banks. With a 1:1 or 1:15 slope until a depth of at least three feet help prevent the establishment of many emergency weeds.
When constructing a pond or reservoir what should be removed before filling with water?
Fertile topsoil
True or false: water can be lowered to expose plants as a form of weed control. This will either freeze or dry the plants for several months
True: depending on the situation. For example, it is not practice to drain canals in the summer months. The species of plant and seasonal growing period will determine practicality of this method
What type of control includes mowing, raking, digging, and pulling weeds?
Mechanical control
True or false: mechanical control methods may sometimes spread the infestation.
True. Attempts to dislodge plants or dragging a chain on the bottom may spread the infestation because weeds can grow from the fragments that float downstream.
What type of control employs plant or animal agents to control vegetation?
Biological
What four primary factors should you consider when considering and herbicide?
Characteristics of environment: population, plant stage growth
Water use: human use, livestock, fish production
Characteristics of water: temp, depth, quality
Herbicide: label, restrictions
What type of formulation is best used for algae or submersed plants because it sinks to the bottom?
Granular
Advantages of ____ herbicides include:
treatment is confined to bottom where plants are rooted
Provides long contact time with plants
Formulated to be non toxic to fish
Granular
True or false: granular herbicides work well in flowing water.
False. They are best used in static water.
True or false: there are few herbicides available for control of weeds in flowing water.
True
Copper sulfate is available for use in flowing water to control ____
Algae
True or false: copper sulfate is toxic to trout and other fish
True
True or false: xylene and acrolein are approved for use in flowing water
True
True or false: xylene and acrolein are highly toxic to fish and other aquatic organisms
True
