Insect: Beetle (Coleoptera:
Brown dot leafy spurge flea beetle
Links Photos: Beetle
sp. Larva Adult 1
Control slide show, Reeves Petrov.
: Europe, Austria, Hungary, and Italy. (1)
One generation per year. (1)
Over wintering stages:
Mature larval. (1)
Eggs are generally laid on the lower stem next
to the soil or on the soil surface during June and July. They
hatch in about 13 days. (1)
: The larvae are active from August until early
spring. There are three Larval instars (developmental stages): the
first lasts about eight days (under ideal conditions), the second
lasts 25 to 30 days, and the final instar requires about 45 days.
A cold period is needed to cause the mature larvae to pupate. The
larval head is well sclerotized (has a hard covering) and sub
compressed and the body is grub-like and whitish in color. (1)
: Pupation lasts about 20 days within a soil
cell, from late spring to early summer.
: Adult beetles are found on the leafy spurge
plants from July until about September with many individuals
surviving and laying eggs for three to four months. Adult are oval
and brown and measure about 3.2 mm (0.13 in.) long. (1)
Adult and larval. The larva have
the greatest effect on the plant.
Leafy spurge, (Euphorbia esula
Host Impact (method/focus):
Adult feeding on the leaves
causes the plant to loose some root reserves. The larval
feeding on the root hairs and young roots have the greatest effect
by reducing the plants ability to uptake water and
nutrients. The plant desiccates (dries out). This
decreases the height attained by the plant, delays the flowering
time, and causes the plant to take its nourishment from the
taproot for other reasons than growth and reproduction. Over
prolonged periods, continuous pressure by the beetles weakens the
plant and can cause death of this hard to control noxious weed.
Favorable/unfavorable release habitats:
infested with leafy spurge are favorable. Areas with
flowering spurge stems that are tall and with a density between 50
and 125 stems per square meter, and with soils between 40% to 60%
sand. These requirements are often found on dry alluvial fans.
This flea beetle prefers warm, open, sunny areas and slightly more
moist conditions that A. nigriscutis
It is now established in Colorado, Iowa, Idaho, Minnesota,
Montana, Nebraska, Nevada, New Mexico, North Dakota, Oregon, South
Dakota, Washington, Wisconsin, and Wyoming. (1)
How to redistribute:
: Areas with flowering spurge stems that are tall
and with a density between 50 and 125 stems per square meter, and
with soils between 40% to 60% sand. These requirements are often
found on dry alluvial fans. This flea beetle prefers warm, open,
sunny areas and slightly more moist conditions that A.
: Collect the beetles with a sweep net and
transport them in a cooler with an ice pack. Within the cooler,
the insects should be kept in paper breathable insect containers
that are not directly touching the ice pack(s). After they
are sorted, they can be shipped or stored on leaf material for
several days if kept cool, or for several weeks under cool
temperatures with with warm feeding and exercise periods every few
days. Also, frozen roots and soil containing the larvae can
be removed from the field in the winter and kept frozen until four
to six weeks before the adults are desired. The beetles can then
be reared at room temperature. (1)
: After this insect is turned loose, leafy
spurge plant density is gently reduced. Roots that are not
attacked including the taproot are able to send up small new
shoots to supply the sugars for root reserves. It is only
through long term establishment of the beetle in a site favorable
to beetle development that the lateral roots of leafy spurge will
be destroyed, the taproots weakened, and many of the plants
finally eliminated from the area. (1)
"This biocontrol agent is established near Whitehall, MT and is
causing reduction of leafy spurge density on most sites." T. Breitenfeldt, WHS science teacher.
brown dot beetle
1. Rees, Norman, et, al., Ed., Biological Control of Weeds in
, Western Society of Weed Science, in cooperation
with USDA, ARS, MT Dept. of Ag, and MT State Univ., Bozeman, Color
World Printers, Bozeman MT, Feb, 1996.
2. Hansen, Rick, Biological Control, A Guide to Natural Enemies in
North America, Cornell Univ. [Online] Available: http://www.nysaes.cornell.edu/ent/biocontrol/weedfeeders/a.cyparissiae.html
. Last modified March 17, 1998.
By: Scott Merkel
By: Joe Wilson 2/15/2000.
Updated By: Trista Zink 3-17-05, Sari Dersam 6/16/16