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Perennial, up to 3 feet tall,
reproduces by vigorous rootstalks and seed. Leaves are
alternate, narrow, 1 to 4 inches long. Stems are thickly
clustered. Flowers are yellowish-green, small, arranged in
numerous small clusters and subtended by paired heart-shaped
yellow-green bracts. Roots are brown, containing numerous
pink buds which may produce new shoots or roots. The entire plant
contains a milky juice. Seeds are oblong, grayish to purple,
contained in a 3-celled capsule, each cell containing a single
seed. Leafy spruge is
native to Eurasia and was brought into the United States as a seed
impurity about 1827. However, it seems to be a serious
problem only in North America where it infests almost 2.5 million
acres, mostly in southern Canada and the northcentral United
States. It has been reported to cause severe irritation of
the mouth and digestive tract in cattle which may result in death.
Capsules explode when dry, often projecting seeds as far as 15
feet. Seeds may be viable in the soil for up to 8 years.
An extensive root system containing large nutrient reserves makes
leafy spurge extremely difficult to control.
Chemical control
Herbicide: Plateau (imazapic)
Description: Apply 8 oz./APlateau
Timing: Apply after summer
dry period when plants begin to grow
Herbicide: Tordon + 2,4-D (picloram
+ 2,4-D)
Description: Apply 0.5 lb ae/A
picloram + 1 lb ae/A 2,4-D
Timing: Apply to bloom stage
Herbicide: Tordon (picloram)
Description: Apply 0.5 lb to
1 lb ae/A picloram
Timing: Apply to bloom stage
Herbicide: Roundup,
Touchdown, etc. (glyphosate)
Description: Apply 0.38 lb ae/A
glyphosate at three times beginning in Jun e at 1 month intervals
or apply 0.75 lb ae/A glyphosate at two times beginning June at 1
month intervals
Timing: June, July and August
Herbicide: Banvel, Clarity,
Vanquish, etc. (dicamba)
Description: Apply 4 to 8 lb.
ae/A dicamba
Timing: Apply spring to early
summer
Herbicide: 2, 4-D lv ester
Description: Apply 1 lb ae/A
2, 4-D to suppress seed production or 6 lb. ae/2, 4-D for control
Timing: Apply to actively
growing plants
Biological control
Insect: Flea beetle (Aphthona
cyparissiae, A. czwalinae, A. flava, A. nigriscutis, and A.
abdininalis)
Description: Adult Aphthona
beetles feed on leaves, and larvae food on root hairs and root
tissues. Collect beetles as adults.
Redistribution: August 1 to
October 1
Insect: Gall midge (Spurgia
esulae)
Description: Larvae feed on
shoot tips and stimulate the production of galls and malformed
shoots. Collect galls in spring.
Redistribution: April 1 to
May 1
Insect: Red-headed spurge
stem borer (Obera erythrocephala)
Description: Larvae feeding
causes shoots to die and reduces root reserves. Adult
feeding has little impact. Collect bettles as adults.
Redistribution: July 15 to
August 31
Insect: Spurge clearwing moth
(Chamaesphecia hungarica)
Description: Root feeding
inhibits shoot production and reduces plant vigor. Collect
moths as adults.
Redistribution: May 15 to
June 30
Insect: Leafy spurge hawkmoth
(Hyles euphorbiae)
Description: Larvae food and
defoliate the plant. Collect H.euphorbiae adults June
15 to July 30 and again August 15 to September 30. Collect moths
as adults.
Redistribution: June 15 to
July 30 and August 15 to September 30
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