Agrilus hyperici
      St. John's wort beetle
      Insect: beetle (Coleoptera: Buprestidae) 
      Biological Control Agent Links

      Origin: Agrilus hyperici's range is found in Southern, Central, and Eastern Europe.  They were first collected in France.  (1,2,3)

      Life Cycle:
      Over wintering Stage: During the over wintering stage the beetle is larval, within the root. (2)
      Egg Stage: Eggs are layed on stems between the height of 8 in (approx. 20 cm) and just above soil level during July and August. (3)
      Larval Stage: The long white larvae have flattened dark brownish heads, and feed within the roots from July through May or June of the folloing year. (1,2,3)
      Pupil Stage: Pupation happens inside of the damaged root during early May to June.  This stage lasts 9-15 days.  (under laboratory conditions).  Initially, pupae are a creamy white, and darken with age.  (1,2,3)
      Adult Stage: Adults are found in July or early August.  They are usually active during the heat of the day.  They disperse readily by flight and feed on the St. John's wort foliage, doing insignificant damage to the plant.  They are also about .02 in (5 mm long) and a reddish bronze color, and a little bit tapered and flat towards the rear.  (1,2)

      Type of Damage to Host:
      Destructive Stage: Larval within the root  (1,3)
      Plant Species Attacked: St. John's wort (Hyperici peroratum), and Hyperici  montanum.  The beetle has also been found on Hyperici concinnum in California. (1,2)
      Location of attack: roots and stem (1-4,6)
      Impact on host: When a larvae is feeding within a root of a plant, it can entirely consume the tissues, severely damaging the plant.  The flower production is reduced because stems produced from an infested root crown are stunted.  Most of the plants infected are killed.  (4-6)

       Release History: First introduced into the U.S.: California in 1950.  (1,2,5,6)  Now established in: Washington, Oregon, Montana, Idaho, and California.  (1-6)

      Habitat: In North America, the beetle is found, for the most part, in the mountain areas.  In Europe, the drier regions are where you can find the beetle.  In a damp site, larvae are subjected to fungal attack. (1-2)

      Availability: The beetle is said to bb available for collection in "limited" numbers. Check with your county extension agent and or county weed supervisor (1,2,5,6)

      Stage to transfer: The beetle isn't ready to be transferred until it's adult stage. (1-6)
       
      Redistribution: You can collect the adults with a sweep net, or hand pick them during their most active part of the day, the hottest temperature.  You can do this during July and August. It is best to release the beetles as soon as possible after collection.  They can be stored for 1-3 days in a refrigerator with some fresh foliage in their container.  They can be transported in a cooler with an ice pack.  (1,3,6)

      Where to purchase: You can purchase this particular beetle on the internet, or through the mail.  (5)

      Remarks: This particular beetle has also been established in Australia.  It disperses widely and in most cases is somewhat lost for years after the release, but then the population grows extremely rapidly and the damage to the weed in readily observable.  Agrilus hyperici will also attack plants in the shade that are not attacked by Chrysolina hyperici.  (1-6)


      Bibliography:
      1.  Rees Norman, Coombs Eric, Piper Gary, and Story Jim, Biological Control of Weeds in the West,   November 1995.

      2. Http://www.mcn.net/~rosebutweed/st1.htm, Rosebud County Weed district, St. Johnswort Borer, contact rosebud@mcn.net

      3.Wysiwyg://14/http://res.arg.ca/leth/weedbio/agrilus.htm, Lethbridge Research Center, updated 7-23-99, Canada

      4. Campbell, C.L. and J.P. McCaffery.  1991 Population trends, seasonal phenology, and impact of Crystolina quadrigemina, Crystolina hyperici (Coleoptera: Chrysomeliade), and Agrilus hyperici (Coleoptera: Buprestidae).

      5. McCaffery J.P., Campbell C.L., and Andres L.A.,  1995 St. Johns Wort,  Pp.281-285 J.R. Nechils et al.  (Eds.), University of California (Oakland), Pp. 356.

       6. Wilson, F.  1943.  The Entomological Control of St. John's Wort (hypericum perforatum L.)  Council of Scientific and Industrial Research, Australia.  Bulletin 169  pp. 87. 


      By: Kenzie Cowling      Published by: Pam McKinney

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