NOT Giant Hogweed!

— Written By

Recently there was a webinar on invasive plants in North Carolina. One of the plants highlighted was Giant Hogweed. All parts of Giant Hogweed are very toxic. The sap of the plant will cause burns if it comes in contact with the skin. Here in Carteret County, that webinar prompted several phone calls and a few emails about plants that are blooming now (mid-July) with white umbel flower heads.

Water hemlock plant covered in umbels of white flowers growing on a ditch bank.

Water Hemlock growing on a ditch bank

Water Hemlock, found here in Carteret County, reaches 4 to 7 feet in height, can be found growing on the ditch bank, has compound leaves and thick stems. All this is similar to Giant Hogweed except that Giant Hogweed reaches heights of 8 to 15 feet tall and the leaves are measured in feet not inches.

After going and taking a look at the plants in question and doing some research. The plants in both locations were identified to be water hemlock (Cicuta maculate). While this particular plant is poisonous if eaten, brushing up against it will not cause burns on the skin.

The U. S. Forest Service has a great webpage on water hemlock that gives some distinguishing characteristics without being too technical. Here are a few of those:

White flowers, s stem with magenta streaks and several compound leaves of the water hemlock plant

Stems, leaves and flowers of Water Hemlock.

  1. The umbels of white flowers are at the tip of the stems and are slightly domed
  2. The leaves are two or three times pinnately compound (the leaf comes off the stem and branches two or three time) having a fern-like appearance.
  3. The veins in the leaves branch at the tip of the vein with one branch leading to the tip of the tooth on the leaf and the other leading to the base of the “V” between teeth.
  4. The stems may have some magenta (red) streaking but not spots.

There are several plants that have a similar appearance to Giant Hogweed growing wild here in Carteret County, but there has yet to be a sighting of the very dangerous Giant Hogweed here. The only known population of Giant Hogweed in North Carolina is in Watauga County in the mountains, so it’s unlikely that Giant Hogweed would be found in Carteret County. U. S. Fish & Wildlife Service has a great website with a list of six plants that look similar to Giant Hogweed. If a plant is seen that looks like giant hogweed, please send pictures and the location of the plant to carteretmastergardeners@gmail.com.

A picture of a roadside ditch with cattails, reeds, and several flowering water hemlock plants growing together.

Water Hemlock growing in a roadside ditch.