Integrated Pest Management (IPM)
      IPM-links       Revegetation
      [ Chemical (Herbicide) Applicators by Montana County ]
      [ Weed Fighting Companies ]
      A weed is a pest!  A weed is any plant that grows where you do not want it to be.  A noxious weed causes environmental and/or economic damage.

      Why should we care about weeds?
      When they invade an area, many aspects of the environment and economy are affected.  These include:
      1. Decreased grazing for livestock and wildlife.
      2. Decreased diversity therefore, decreased stability of the ecosystem.
      3. Increased soil erosion.
      4. Decreased water quality and fish habitat.
      5. Decreased amount of food we can produce through ranching and farming.
      6. Decreased tourism.

      Montana farmers and ranchers spend $100 million a year just to control weeds.  This money could be spent in other areas of the economy.

      Studies show that knapweed alone costs Montanans $42 million in lost tourism every year.  This $42 million in lost dollars would support about 500 well-paying jobs in Montana. (1)

      Why are many weeds hard to control?
      1. They produce many seeds and thus spread rapidly.
      2. They have deep roots.
      3. They are not palatable to livestock and wildlife therefore, these grazers eat the other desirable plants first, leaving the weeds to flourish.
      4. They are invader species.  They are adapted to rapidly colonize disturbed areas.
      5. They have allelopathy- they give off chemicals that inhibit the growth of other plants.
      6. They have waxy leaves so herbicides do not stick to the plant.


      So, how do we control these unnatural, unwanted foreign invaders?  No one way completely works therefore, our best strategy is a mixed bag of methods used together.  This is called:
      INTEGRATED PEST MANAGEMENT (IPM)
      The methods:
      1. Prevention- Keeping weeds out in the first place.
      2. Chemical- Using chemicals such as herbicides that control or retard the growth of weeds.
      3. Biological Control- Using beneficial creatures such as insects or fungi that damage the weeds.
      4. Mechanical- Tilling (plowing) or hand pulling the weeds.
      5. Controlled Burning- Safely burning the weeds.
      6. Grazing- Using grazing animals such as sheep or goats that will eat the weeds.
      7. Revegetation- reseeding a disturbed site to block or choke out the weeds.
       
      IPM
      CHART
      FAST ACTING
      LONG LASTING
      ENVIRONMENTAL SAFETY
      PERSONAL SAFETY
      EFFECTIVENESS
      PREVENTION
       
      +
      +
      +
      +
      +
      CHEMICAL
       
      +
      0
      0
      0
      +
      BIOLOGICAL
       
      -
      +
      +
      +
      +
      MECHANICAL
       
      +
      0
      +
      +
      +
      CONTROLLED BURNING
      +
      -
      +
      0
      +
      GRAZING
       
      +
      -
      +
      +
      +
      REVEGETATION
       
      -
      +
      +
      +
      +
      0 = Neutral (mixed)           + = Positive             - = Negative
      As compared to the other methods.

      Explanation:

      Prevention:
        Examples:
          -Washing the undercarriage of the car to remove seeds.
          -Using weed seed free hay to feed horses on pack trips.
          -Not moving soil or gravel with weed seeds in it.
        + 1. Fast acting: Occurs even before the weed is present.
        + 2. Long lasting: If prevented, will not occur
        + 3. Environmental safety: These are all safe to the environment.
        + 4. Personal safety: Most prevention is quite safe.
        + 5. Effectiveness: Keeping weeds out works if we all work together!!
                        "An ounce of prevention is worth a pound of cure."
      Chemical:
        Examples:
          -Most commonly used herbicides to control Noxious Weeds: Tordon 22K, Hi-Dep, 2,4-D, Banvel, Curtail, Transline, Escort and many others.
        + 1. Fast acting: Most herbicides show immediate results.
        0 2. Long lasting: Most herbicides quickly break down in the environment and need to be reapplied
                    yearly.  However, some types last many years in the environment (soil sterilants).
        0 3. Environmentally safe: Herbicides need to be applied correctly, each person who wants to apply
                    restricted use herbicides needs to get her/his private applicators license. Improperly applied
                    herbicides can be unsafe to the environment, but when applied correctly are a benefit to the
                    environment as they control the noxious weeds that would otherwise cause vast environmental
                    damage.
        0 4. Personal safety: By following label directions and wearing Personal Protective Equipment (PPE) the
                    risk to humans is minimal. The improper use of herbicides may cause harm to humans.
        + 5. Effectiveness: Herbicides used correctly, with proper timing, do control weeds well.
      Biological:
        Examples: (Biological Control Agents)
          -Releasing an insect whose larvae eat the roots of the weed.
          -Releasing a round worm (nematode) or a mite that causes a gall (swelling) on the plant.
          -Infecting the weeds with specific fungi that damage that weed.
        - 1. Fast acting: Biological control agents are often hard to establish.  Once they do establish, their
                    population often takes many years to build up to levels where significant damage to the weed
                    infestation can occur.
        + 2. Long lasting: Once established on a site, these agents will be there as long as the weed is present.
                    They will also spread (disperse) across property and political boundaries.
        + 3. Environmentally safe: Many biological control agents are ecological specialists.  That means that
                    they eat only one type of plant (the weed!) and often even feed on only one part of one type of
                    plant.  These agents have been rigorously scientifically tested to be sure that they are species
                    specific feeders (i.e. are safe) before release.
        + 4. Personal safety: "They only bite weeds!"
        + 5. Effectiveness: In the long run, just as they keep these foreign plants in check in their native
                    Eurasian habitats, they may finally work in many of our North American habitats.
      Mechanical:
          Examples:
                    -Tilling (plowing) weed infestations to control the weeds.
                    -Hand pulling the weeds, along with proper disposal.
                    -Watering a weed infestation to allow more desirable plants to out compete the weeds.
        + 1. Fast acting: Plowing and hand pulling control the weed immediatly.
        0 2. Long lasting: Surviving roots and seeds left in the soil can sprout.  Remember, the seeds of some
                    weed species can stay viable in the soil for up to 10 years.  Therefore, the site must be
                    inspected and new sprouts pulled for 10 years!!
        + 3. Environmentally safe: Tilling and watering are similar to farming and gardening.
        + 4. Personal safety: Wear gloves when hand pulling to avoid exposure to the toxins in some noxious
                    weeds.  Be careful not to injure your back while stooping and pulling deep rooted species.
        + 5. Effectiveness: When done consistantly and properly tilling, hand pulling and watering can be very
                    effective.  Be sure to properly dispose of pulled plant (weed) matter so as to prevent seeds/roots
                    from sprouting in new areas. 
      Controlled Burning:
        Examples:
                    -Carefully burning an area infested with noxious weeds and then reseeding the burn in grasses
                    and/or native plants.
        + 1. Fast acting: Fire rapidly destroys the above ground portion (tops) of most weeds.
        0 2. Long lasting: Most fires do not get hot enough to damage the roots or buried seeds of noxious
                    weeds.  However, the stems, leaves flowers and seed heads can be severly damaged.  Many
                    weeds will quickly resprout after a fire.  Infact, some noxious weeds are stimulated to produce
                    more stems after a fire and also benefit from the nutrients released from the ashes of the fire.
        + 3. Environmentally safe: Northern Rocky Mountian and plains ecosystems are well adapted to fire.
                    Control measures such as hand dug fire lines generally cause more damage than the fire.
        + 4. Personal safety: When done with the proper equipment and personal, controled burning is quite
                    safe.
        + 5. Effectiveness: Many species of noxious weeds are severly damaged by hot, properly timed fires.
      Grazing:
        Examples:
                    -Using sheep to graze a patch of leafy spurge just as it starts to flower can severly damage the
                    foliage and seed production.  The sheep seem to "develope a taste" for the weed.
                    -Fencing goats onto a small area infested with spotted knapweed will cause them to eat the
                    knapweed to the ground.
        + 1. Fast acting: A large number of sheep and/or goats in a small area can rapidly damage a weed patch.
        - 2. Long lasting: When you take the animals out, the noxious weeds can quickly resprout new tops.
        + 3. Environmentally safe: Well managed grazing is safe.
        + 4. Personal safety: Sheep and goats are generally save animals.
        + 5. Effectiveness: Yearly grazing at the proper time can severly damage foliage and seed production of
                    many weed species.  Be sure that enough time passes before you move the animals to an uninfested
                    area so that seeds in the digestive tract have passed through the animal and so that seeds stuck to
                    the fur (wool) have had time to fall off.
      Revegetation:
        Examples:
                    -Rapidly reseeding grasses and/or native plants after a controlled burn.
                    -Immediatly reseeding the ditches and banks of a new road.  These desirable plants compete with
                    weeds that may sprout in these distrubed areas.
        - 1. Fast acting: It takes a long time and healthy ecological conditions for reseeded plants to compete
                    with weed infestations
        + 2. Long lasting: Once established under healthy conditions, desirable plants can compete with potential
                    weed invaders.
        + 3. Environmentally safe: Planting native plants is environmentally safe.
        + 4. Personal safety: Similar in safety to farming and gardening.
        + 5. Effectiveness: When done in a timely fashion and with the correct plants for the site, these plants can
                    effectively compete with many weed species.
        (1) Schmidt, Lisa, Madison-Jefferson Extension Agent, P.O. Box 1079, Whitehall, MT 59759, (406)287-3282.

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