Family Apiaceae

Wild Parsnip is in the Apiaceae – the carrot family – and like carrots, the roots are edible.  Wild Parsnips are native to Eurasia, and were introduced to the U.S. by European settlers.

Wild Parsnip is very prolific – producing many seeds, and advancing quickly into areas of native plants.  And its sap causes painful blisters on people’s skin when exposed to sunlight.  It’s on  many states’ noxious weed lists.

Wild Parsnip is a biennial, producing a rosette of two or three leaves the first year, and a single flowering stalk the second year.  It grows in open areas and wetlands – not in standing water, but in areas with plenty of moisture.

First year plant

 

Second year flowering plant, with the center flower starting to form seeds.

 

This is one of our wetland fields, taken over by Wild Parsnip

 

We have about 50 acres of wetland, and there’s Parsnip in nearly all of it.  We started trying to eliminate it on our western border, and we’re slowly working our way east.  I think we’ll always have some parsnip, but I’d love to get it to the point where we only have to spend a few days on control every year.

We’ve found two methods of control that seem to work well: Mowing and Pulling.

Mowing
Where there are dense patches of second year plants, we mow just when the plants are beginning to come into bloom.  The mower always misses some plants, and the mowed plants sometimes send up new flower stalks.  If possible, it helps to mow again, just as the newly sprouted flowers are starting to bloom, but we don’t usually get around to it.  Even mowing just once reduces the number of seeds produced dramatically.  We mow dense areas for two or three or four years until the number of plants is small enough that they can be pulled.    (It’s important to mow with something that doesn’t spray plant bits up into the air and onto the person who’s mowing.)

This field is being mowed for parsnip.

 

After mowing for a few years, and the density of second year plants is lower, I pull the ones that are left by hand before they go to seed.

Pulling
I prefer pulling to mowing if possible – it can be done in places the tractor can’t get to or where the soil is too wet, and it allows the native wetland plants to bloom.

The most important part of pulling is protecting your skin from contact with the plant.  Here’s my parsnip pulling outfit.  (The only thing missing is a waist pack that I wear to carry my clippers and a dauber filled with glyphosate.)

– The netting is to keep the gnats away, and also to protect my face from stray pieces of parsnip.
– The shovel is a Parsnip Predator, a special shovel that I use to cut the root below the soil.
– The purple bag is to hold seeds that I need to carry away so they don’t make new plants.
– The hand clippers and dauber are to cut and treat any plants that I can’t pull.

I used to have trouble protecting my wrists – I’ve gotten several blisters where my shirt cuffs and gloves didn’t quite meet.  Now I sew pieces of velcro to the cuffs of my shirt, and the glove fabric sticks to it, closing that gap.

 

Wild Parsnip roots are large and sturdy.  If the ground is wet – in wet soil, or after a big rainstorm – they can be pulled out of the ground fairly easily.  This method is very fast and works well.

 

If the ground is drier, they’re harder to pull.

Most of the time I use a special shovel – designed to cut, not to dig – to cut the root below the surface.  The Parsnip Predator is designed to remove Parsnip, and other tap rooted plants.  I push the blade down near the root at an angle so it cuts the root about an inch below the surface.

 

Then I can easily pull out the top of the plant.  Here’s the top of the plant with the cut root.  Once it’s been cut, the root that’s still in the ground dies.

 

The other possibility is to cut off the stalk close to the ground, and treat the cut stump with herbicide.  For treating I use a buckthorn blaster filled with 10-20% glyphosate.  I do this along our gravel driveway or along the roadside, where the plants are difficult to pull and I can’t get the shovel into the ground.  This method also works along the steep banks of the creek.  I can walk in the creek, and reach up to cut and treat plants along the edges.

The best time to pull plants is when the flower stalks have elongated, but before the flowers have started making seeds.  If the seeds haven’t started forming, I just drop the pulled plants on the ground and they decompose.

If seeds have started forming, I cut off the seed heads and collect them in the bag I carry over my shoulder.  (I used to collect and carry away the whole plants, but that’s a lot more work.)  I dump the seed heads onto our compost pile.  Most of them get covered up with other weeds so the seeds don’t sprout.  Some seeds do sprout, but it’s easy to keep an eye on the compost area, and easy to either spray or pull plants that come up.

Flowers with seeds forming

 

When the seeds look like this, the plant is starting to dry up, and I can leave the root in the ground, and just cut off the top.  But the season for working on parsnip is almost over.

 

This picture shows some very dry seeds – they’re starting to fall off the plant.  It’s still worth cutting and removing as many as I can – it prevents a lot of new plants from getting started.

 

In spite of the fact that Wild Parsnip isn’t native to the U.S., a few insects nectar at the flowers and eat the leaves.

Baltimore Checkerspot butterfly

 

Black Swallowtail caterpillars will eat Wild Parsnip.

 

Ants on Wild Parsnip seeds

 

Aphids

 

Borer Moth caterpillar – Papaipema species – boring inside the stem.

 

Purple Carrot Seed Moth caterpillar – feeds on plants in this family

 

Brown Wasp Mantidfly – probably hunting prey on the flowers

 

Parsnip Webworms came here from Europe, probably sometime in the 1800s.  They’re the caterpillars of small moths that eat Wild Parsnip and several related plants, but don’t seem to have enough impact to really affect its spread.

Here’s the caterpillar of the Parsnip webworm.

 

Here it is inside it’s ‘nest’ on a parsnip plant.

 

And here’s an adult Parsnip Webworm moth.

 

This is a disease called Aster Yellows.  It prevents the plants from forming functional flowers and seeds.  It’s transmitted by hoppers which don’t overwinter here – they fly up from the south in the spring.  So in years when there are lots of those hoppers, there are more diseased Parsnip plants – but not enough.