A huge and toxic weed

After my October column on weed management appeared, I received several emails on the subject. One reader reported a giant weed growing in the northwest corner of San Francisco. When I saw the photos, I could identify it as pokeweed, a plant not common in our area.

This weed, named Phytolacca americana, grows 4 to 10 feet tall. The plant has simple, oval pointed leaves, 5 to 10 inches long, on long stems. The white or greenish flowers bloom on spikes, known to botanists as racemes, which can be as long as 8 inches. The tightly clustered ripe berries are dark purple, their short stems bright pink. These berry spikes are the easiest part of the plant to recognize.

All parts of pokeweed are poisonous. The roots are the most toxic part, but even the berries and their seeds have poisoned babies and small children who found them tempting. In addition to direct poisoning, the toxins in pokeweed have been linked to mutations and birth defects.

Birds, including northern mockingbirds, mourning doves and cedar waxwings, enjoy the berries, are immune to the toxin, and spread the seed. Raccoons and opossums also seem to escape harm when they eat the berries, but many mammals would be poisoned.

If you are trying to get rid of pokeweed, the best method is to dig it out so the perennial tap roots can’t grow new shoots. Then clean up any berries you find on the ground. Watch for seedlings from seeds you missed, and pull them when they are still small. Wear gloves when handling this plant, as the toxins can be absorbed through skin.

Even though it is toxic, some people grow this plant as a garden perennial. The variety Silberstein has pale, cream-colored leaves with green spots; another, named Sunny Side Up, has yellow-green leaves.

Pokeweed is native to the eastern half of the country. People in Appalachia and the South traditionally eat the leaves of very young pokeweed plants, but only after taking precautions to remove the toxin. This is done by boiling the leaves, discarding the boiling water, and repeating this process two or three times. The resulting cooked green is known as “poke sallet.” (It’s important to know that the word “sallet” is from the Middle English word meaning cooked greens, not salad, since the raw greens would be toxic.)

Caitlin Atkinson / “Designing With Succulents” “Designing With Succulents” includes a Bay Area garden (left) that uses a copper fountain as a focal point amid succulents; and a balcony in downtown S.F. (this page) with sleek, sculptural succulents.