Wild parsnip and giant hog weed, oh my – Audio

Wild parsnip and giant hog weed, oh my - Audio

Wild parsnip and hog weed

Mark Renz, Extension Agronomist
Department of Agronomy
UW-Madison College of Agricultural and Life Sciences (608) 263-7437, (608) 262-1390

3:09 – Total Time
0:12 – Wild parsnip
0:42 – Livestock beware
1:17 – Hog weed a nasty customer
1:55 – Hog weed localized
2:24 – Mowing, herbicides
2:45 – For more information
3:01 – Lead out


Sevie Kenyon: Some weeds to be looking out for, we’re visiting today with Mark Renz Department of Agronomy University of Wisconsin-Extension in the college of Agricultural and Life Sciences and I’m Sevie Kenyon. Mark, we got some weeds to be looking out for, what are they?

Mark Renz: Today I want to talk about some of the weeds that we’re seeing on our roadsides in particular; it’s been another really good year for wild parsnip. This is the plant that’s getting anywhere from two to five feet tall, yellow flat top flowers, that’s flowering right now along many of our roadsides in Wisconsin. This is a real big problem because if you get the sap on your skin and that skin is exposed to sunlight, you can get a really bad burn that often is described as similar to battery acid, so it’s one to really be on the lookout for.

Sevie Kenyon: Can wild parsnip end up in livestock feed?

Mark Renz: Surprisingly, it can end up in livestock feed and it has been implicated as being poisonous to livestock but it actually is a much more complicated and nuanced story and often has to do with the skin color of those animals. If they are light skin color they can get a similar reaction to what we get if they’re dark skin they tend to actually, actively look for it and graze it and have no impact at all so it’s one of those that really depends on the animal. In general, what we recommend is never feed more than 20 percent forage that consists of this wild parsnip.

Sevie Kenyon: Mark, what other plant should we be looking out for this summer yet?

Mark Renz: Well, I think the other one that we’ve had a lot of reports on and to keep a look out for it was is called Giant Hogweed. This is a plant in the carrot family like wild parsnip we talked about, but it just gets massive and has these very tall, white flat topped inflorescences, but this plant will be 10-15 feet tall and have stalks that are as round as your wrist, so very, very large, and it even causes even worse burns than we do see with wild parsnip. We just recently confirmed a new population in Sheboygan County and a lot of other potential cases have recently come in.

Sevie Kenyon: Mark, let me ask a little bit about that, how widespread are these weeds?

Mark Renz: So, the Giant Hogweed is very isolated, looks like it’s being spread through people doing purposely planting it in urban cultures what we tend to do is get a lot of false reports on look-alike species like Cow Parsnip as well as Angelica these can easily be differentiated by looking at the size of the plant and looking at the leaf structure we just recommend that you contact your local county agent to get some of the specific information to make sure you’ve identified it correctly.

Sevie Kenyon: What are some of the control measures for these weeds?

Mark Renz: Well like anything else there is a wide range of control measures that often depends upon the environment that we’re working in, a lot of mowing can be effective. We need to be careful that we limit our exposure, so often mowing isn’t a good option. Another option that we can rely on is use of herbicides and used at the correct timing they can be really effective.

Sevie Kenyon: Mark where should people go for more information?

Mark Renz: We have a plethora of information that’s available on fact sheets on wild parsnip. Probably the easiest thing to do is just to get on your computer and do the local search engine of UW Weed science can also go to your county extension agent and they get you in touch with some of the latest and greatest information.

Sevie Kenyon: We’ve been visiting with Mark Renz Department of Agronomy University of Wisconsin-Extension/Madison in the college of Agricultural and Life Sciences and I’m Sevie Kenyon.