Example Noxious Weed Research Paper
      Sections Labeled
      As written by a 7th grade student, no changes.  Teachers, feel free to use this.
      Students, do not copy this to use as your own paper!
      Title:
      Knapweed: The Plant Killer

      Attention Getter:
          Imagine that you are riding your horse in the woods and you get off to rest and let him graze.  After a while you come back and he is breathing really hard.  He lies on the ground and is breathing a lot harder.  Slowly, you watch your horse die!  You start to walk home very disappointed, wondering how to tell your parents about your horse being poisoned by a noxious weed....

      Introduction:
          In this report I will tell you about: 1) where spotted knapweed grows, where it came from, and how it spreads, 2) the effects it can have on the environment, 3) the herbicides that kill or damage spotted knapweed, and 4) the insects that can kill or damage spotted knapweed.

      Body:
      Topic Sentence 1:
             Spotted knapweed first started to grow in Central Europe and East to Central Russia, Caucasia, and Western Siberia.  Spotted knapweed came into North America in the late 1800's as a contaminant in alfalfa.  Early introductions were also through discarded soil used as ship ballast. The first record of spotted knapweed was in Victoria, British Columbia, in 1883.  This weed grows in all 56 counties in Montana and in 25 other states in the U.S.  This weed also lives in parts of Canada. (1)
              Spotted knapweed grows almost anywhere.  It will grow in or on grass, crop fields, and almost any where else you can think of.  Knapweed will not grow in mining tailings or in solid rock. (2)  Knapweed lives mainly in a temperate climate. It does not need a lot of water because of its long tap roots.  It does not have to battle for water with other plant because it kills the plants around it. (1)
              This weed spread further in domestic alfalfa seeds and hay before it was recognized as a serious problem.  Spotted knapweed populations are largely extended through peripheral enlargement of existing stands.  Seed production of a knapweed can be 5,000 to 40,000 per square meter per year.  Bracts of the flower heads open when dehydrated, two to three weeks after maturity, and wind or passing animals can flick the loosely held seeds up to one yard from the parent plant.  Long distant transport occurs when seeds become attached to passing animals, or by rodents and birds.  Spotted knapweed flower heads also become attached to the undercarriage of vehicles, are transported long distances in mud, and commonly become attached to or drop into shoes.  Seeds of spotted knapweed spread through rivers and along watercourses and they are transported in crop seed and hay. (1)
      Topic Sentence 2:
              Spotted knapweed affects the environment in many ways.  Spotted knapweed reduces livestock and wildlife food.  Researchers found that spotted knapweed infestations decreased blue bunch wheatgrass yield by 88%.  Elk use, as estimated by pellet groups, was reduced by 98% on spotted knapweed-dominated range compared to bunch grass-dominated sites.  Spotted knapweed dominance on bunch grass rangeland is also bad for water and soil resources.  If some animals, like horses, eat knapweed, they will have a bad reaction to it. (1)
              Knapweed can have a bad effect on grass and other plant life.  Knapweed has a poison in its leaves that most plants die from.  This allows the knapweed to kill plants that are around it.  If a knapweed plant gets into a field where crops are being grown and goes undiscovered for a while the knapweed can decrease the crop.  The poison in the leaves may last for several years after the knapweed has been removed. (2)
      Topic Sentence 3:
              There are many ways to control spotted knapweed with chemicals.  Tordon is a very strong chemical that can kill knapweed and last for about three to five years.  In order to spray with Tordon you need a special permit through the State Weed Board.  When you spray with Tordon you should put a dye in with the mixture to tell you where you sprayed.  You should keep livestock off the sprayed area for about two weeks. (2)
              You can buy mixtures of chemical to spray weeds with at hardware stores.  Most of those chemicals aren't as strong as Tordon, but can kill some of the weeds.  One of the chemicals that you can buy is called Roundup.  You can buy chemicals in a store already mixed up or the type where you have to mix it up yourself.  People who want to spray a little area buy Roundup or something similar to it.  Spotted and diffuse knapweed can be controlled by spraying with Stinger.  Control is inconsistent and short term with 2,4-D and Banvel.  For long term treatments you must apply it annually until no viable seed remains in the soil.  Montana State University (Bozeman, Montana) research shows that 2,4D, Banvel, Stinger, and Tordon were most effective when applied during May to early June when most of the plants are sending up a seed stalk. (3,4)
      Topic Sentence 4:
              There are some insects that kill or damage spotted knapweed.  The Seedhead Weevil (Bangasternus fausti) originated in the Mediterranean region and targets both spotted and diffuse knapweed.  All stages of the larvae feed within the seed head resulting in almost total destruction of the florets, seeds, and receptacle.  The Seedhead Weevil produces one generation per year.  Females lay from 150 to 300 eggs during the three-month period in which the female lays eggs.  A single female may lay up to 15 eggs in one day.  Each egg is sealed to the plant with an excretion that serves to protect the egg and newly emerged larvae.  The larvae feed in the seed head and terminate seed production.  Pupation occurs within a chamber in the middle of the seed head.  Adults emerge about 32 days after the egg had been laid. (5)
              The Root Boring Moth (Agapeta zoegana) originated in Europe and attacks the roots of spotted knapweed.  Feeding of the late instar of the larvae causes considerable damage to the root, especially on small roots or when several larvae are present.  Larval feeding may cause total destruction to smaller roots.  This insect produces one generation a year.  Eggs are laid within crevices of stems and leaves on the host plant.  Green plant material must be present.  Eggs hatch seven to ten days after being laid.  The larvae move directly to the root crown area where they begin to mine into the roots.  Pupation occurs within a pupal cell usually attached to the root at the root crown area.  Adults emerge in the field between May and September depending on local climate conditions. (5)
              A Gallfly (Uraphora affinis) which originated in Europe and Asia Minor attacks the seed head of spotted knapweed.  The larvae cause the formation of galls resulting in destruction of seeds.  The galls also act as a nutrient sink reducing overall plant vigor.  The Uraphora affinis gallfly lays eggs into immature flower heads and produces one generation per year.  The developing larvae induce the formation of a gall which provides protection and nutrients for the developing larvae.  As spring time temperatures increase, larvae pupate and emerge about the time flowers are present on the knapweed plants.  Adults of Uraphora quadrifasciata appear to be able to disperse a greater distance than Oraphora affinis. (5)

      Conclusion:
              In this report I told you about: 1) where spotted knapweed grows, where it came from, and how it spreads, 2) the effects they can have on the environment, 3) the herbicides that kill or damage spotted knapweed, and 4) the insects that can kill or damage spotted knapweed.  In my opinion, spotted knapweed is a weed because it causes major damage to farmers, ranchers and wildlife.  I am ready to help land owners with the knapweed problem!  When I see the plant, I pull it!!  Good luck in your fight against this plant killing noxious weed!!!  I hope this paper will help you!!!!

      Bibliography:
      Bibliography

      (1) Weed control notes, Montana Weed Control Association, [website]:
                  http://www.mtweed.org/Identification/Knapweed/knapweed.html, 5/12/99.

      (2) Weed control notes, Crane, William II, 5/17/99, 971 Hwy 2, W. Whitehall, Montana .

      (3) Biology and Management of Noxious Rangeland Weeds, edited by Sheley, Roger L., and Petroff, Janet
                  K., EB, Montana State University, Bozeman, Montana.

      (4) Controlling knapweed on Montana Rangeland  by Lacey, C.A., Lacey, J. R, Fay, P. K., Story, J. M.,
                  and Zamora, D.L..

      (5) Weed control notes,  [website] http://www.cariboord.bc.ca/knapweed/htm.


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