Leafy Spurge
Scientific Name: Euphorbia esula

History/Origin
          This native of Eurasia (Central Europe and east to Central Russia) was first brought into the United States around 1827 as an ornamental. Soon after, it escaped and moved into yards and household gardens. By the early 1900's, leafy spurge had spread from the East to West coast.

Biology/Ecology
          Leafy spurge plants reproduce in two ways: vegetatively and by seed. Vegetative spread is accomplished by sending up new shoots from the roots. Small buds growing along each of the roots have the potential to grow into a completely new individual plant. These buds are activated when the plant is damaged in some way (mowing, grazing, fire, plowing, etc.). These new individual plants are usually stronger and healthier than those grown from seed, due to the existing root system.

          Reproduction by seed starts with the dispersal of seeds. Leafy spurge flowers usually develop two weeks after the larger yellow-green bracts that surround them (May to early June in northern climates). Each flowering stem produces an average of 140 seeds that develop in three-lobed capsules. Twenty to thirty days later when the capsule is dry, it explodes, throwing seeds up to 15 feet away. These seeds float well and establish easily along waterways. Dispersal also occurs in mud that sticks to vehicle and bike tires, boots, and animal feet and hair. Seeds have been known to travel through the digestive tracts of animals (birds, goats, sheep, rodents, and whitetail deer) and establish well in the resulting dung. Seeds can live for over eight years in the soil, with most germinating within the first two years. Seedlings can emerge from four inch depths. Eighty percent of the seedlings die, but those remaining become highly competitive within four months.

          The above-ground portion of the plant may stand up to three feet tall, but below ground is where you will find most of the plant. The root system of these plants can grow over 26 feet down and 15 feet across (seedlings can produce a root system three feet deep and 40 inches wide in only four months). These roots provide storage for a large nutrient reserve and can move herbicides out of the plant and into the soil, making the plant very difficult to kill.

          Within the leafy spurge plant, there is a cell known as the laticifer. This cell can run the length of the plant, making it one of the largest cells known to man. It acts as waste disposal site (the plant's version of a hazardous waste dump) where undesired chemical byproducts are kept in a latex solution. In some instances leafy spurge plants have been sprayed with an herbicide only to have the plants place the chemical in the laticifer. This prevents the herbicide form interacting with the vital functions of the plant. The white-colored latex that is found in the lattisifer deters herbivory and can be a skin and eye irritant because of the chemicals within it.

Known Impacts
Detrimental:
           This plant is known to force out native plants through competition, and in many cases, forms a monoculture. This loss of plant diversity reduces wildlife forage and habitat. Leafy spurge populations as small as 10-20 percent of the total plant community have discouraged cattle from grazing. When it is grazed by some domestic or wild animals, it can cause severe irritation to their mouths and digestive tracts. With current laws, the required control and management of this plant has lowered the financial value of infested lands.

Beneficial:
           In some cases, this plant has been effectively used as forage by sheep and goats. It has also proved to be a good food source for seed-eating birds and rodents. Leafy spurge has also been used as a fuel. Chopped up and pressed into pellets, it is burns like coal and releases considerable energy. The latex found in the laticifer can be used in the production of commercial latex.

Potential Locations
          Leafy spurge can grow in many different areas. This plant can grow anywhere from hot, hilly rangelands to cool, wet riparian areas. It often dominates bottom lands, and is less abundant in the uplands (upper slopes, summits, and ridge lines). Primary locations include: pastures, rangelands, roadsides, waste areas, and areas disturbed by recreation and development.

Control/Management
          Management of this weed must be considered a long term project. All tools available have been used with varied success. The more effective methods include:
• Prevention: not letting it get an established foothold (true for all weeds, but especially true for this one).
• A combination of reseeding and spring grazing with sheep (when they prefer forbs to grass). This decreases the competitive effectiveness of leafy surge over time.
• A combination of domestic stock and insect grazing. Graze in the Spring and in the Fall to avoid insect breeding schedules.
• A combination of herbicide application, and reseeding (example herbicide: Clarity, Tordon 22K, 2-4,D, Roundup Ultra [look at herbicide label: free search]).