Dalmatian toadflax is adapted for survival and spreading.  It is capable of surviving rapid and extreme temperature changes.  One plant can produce 500,000 seeds that can float on water and can remain viable in the soil for 10 years.  The plant also spreads from its roots.  Roots can spread 4 to 10 feet below ground and extend as much as 10 feet from the parent plant to send up even more plants.  Because of this extensive root system, hand pulling, mowing and burning have little effect on a stand’s survival.  Herbicide must be applied at high rates potentially damaging native or preferred forbs.

So what’s a land manager to do?  Graze it!  I trained cows to eat this plant in 2008 in Boulder County, Colorado and they have been eating it in pasture ever since.  Likewise I worked with folks in Roundup, Montana to teach their cows to eat it.  Once cattle had learned to graze the plant they were released into a very large pasture.  Observers found that in spite of the size of the pasture and the spread of the plant, most plants had been grazed to some degree after the first year.    

You might be surprised to find that, contrary to some information provided on the internet, Dalmatian toadflax is not toxic to livestock.  As always, before deciding to train animals, I did thorough research on this plant.  In this case, Dalmatian toadflax does not appear as a toxic plant in the most respected texts in this area:

“Toxic Plants of North America” Burrows and Tyrl
“A Guide to Plant Poisonings of Animals in North America” Knight and Walters
“Poisonous Plants” Frohne and Pflander
“Natural Toxicants in Feeds, Forages, and Poisonous Plants” Cheeke

Both Dalmatian and yellow toadflax contain quinazolene alkaloids, vasicine, vasicinone and deoxyvasicinone, as well as some flavinoid glycosides.  Vasicine can cause bronchodilation (expansion of the airways) which is probably why Native Americans burned it in sweat lodges.  But otherwise no problems have been shown for animals eating it.  There are some other things I would watch for in yellow toadflax, but again, nothing of great concern.

As with all forages, timing of grazing of Dalmatian toadflax is important.  Animals will graze it more readily in rosette and bolting stages when it is more nutritious.  You’ll notice the amount they eat drop off as the plant matures into seedset.  This past summer my Boulder County, Colorado trainees grazed a lot of Dalmatian toadflax, moving from plant to plant just as they would when grazing grass.  Sometimes they ate entire stems, others they grazed the tops and leaves off of stems as in the picture shown here.

Plants were in full flower when we put the trainees in this pasture.  Our goal for this pasture is to reduce weedy species and increase native grasses and forbs.  So, this coming spring we plan to put them in even earlier so they can graze more of the weeds that come up early in the spring.  You should adjust your own grazing timing based on what grows in your pastures and your own goals.