Leafy-Spurge Control

[Muttley]

I have been battling spurge for years in my pasture. We tried the beetles but are finding that they can not control fast enough. For years I have been spraying a high volume of 2-4D and Banvel on it. The last couple of years I have felt that the chemical was doing very little if anything. I am assuming that the plants are becoming tolerant of the chemicals.
What else is there I can try? I have heard that the states have some chemicals out that work pretty well, I wonder if this is true and can we get them in Canada.
Much of the spurge has gotten into places that we can not get to except by plane.
I really don't care about loosing some grass or trees trying to get this weed, I can allways replant.

[cowman]

Tordon 22K will get spurge. It has only recently been allowed for use in pasture, as it is basically an industrial spray. I believe you have to get approval to use it. It is definitely not cheap but really works. It also gets toadflax which is another toughie. Dow-Elanco make it.

[Muttley]

Will Tordon 22k kill spurge or just set it back?

[cowman]

It will kill it and it will kill any seedlings for five years. Tordon 22k is very residual thus the heavy restrictions on it. Picloram(the main ingredient in Tordon) doesn't break down very easily in the soil and it forms a layer. When seedlings sprout they do well until their roots get down to this layer and then they die. The layer is the where the mature plants roots extended to. Tordon is only a broadleaf herbicide and is very easy on grass. It is also one of the safest chemicals for mammals and insects, having a LD number better than even Round-Up. Tordon 22K is used extensively on oil and gas leases as well as on municipal roads. There is also another product Tordon 101 that is now being marketed as Graze-On. It is a combination of picloram and 24D and is an excellent thistle control but will not get the toughies like spurge,toadflax or field scabeous. By the way you should be careful using Tordon 22K as it likes to move in sandy soils and it will definitely kill trees.

[nakodo]

I have heard the killing the top growth over and over (ie intensive grazing with sheep or goats or by mowing regularly) decreases the root strength and eventually the combination of herbicide and root reserve depletion kills the plant.

Just some ideas..

[cowman]

The trouble with spurge is it can increase very rapidly in a few years. That is why it is a noxious weed in Alberta...I don't know about Sask. or Manitoba. Being a noxious weed it must be controlled(it's the law) or you will have your local weed inspecter calling! The problem with plants like spurge,field scabeous, toadflax is the leaf structure. Narrow leaves that don't allow absorbtion of most chemicals. I've often wondered if Banvel/24D with an adherent might do the trick. 24D can usually enter a plant but not if it has a waxy leaf. Super Sticker(an adherent) helps 24D enter a plant and works very well. It works on Snowberry bush which has to be one of the toughest weeds around.

[dickens]

An excellent resource website (US based but still very informative) is Team Leafy Spurge at:

http://www.team.ars.usda.gov/

Check it out. The main thing with spurge is to understand that you are fighting a creeping rooted perennial. Seeds are a secondary concern at best. Established patches have a web-like network of runners underground that send up multitudes of aerial shoots. When you cut or spray it, the established root system's response it to use its reserves to send up even more shoots the following year. DONT DESPAIR - this means you have hurt the plant and it is now having to draw on root reserves to sustain itself. Repeated and diligent management of spurge, and encouragement of competitive grass and crops are the keys to managing spurge. Eradication is likely a pipe dream, but you can keep ahold of it if you work consistently year after year.