Musings of a roaming nature nerd

The Nasties: Poison Oak & Stinging Nettle

The last month of field work has just begun, which means the start of vegetation surveying and the start of a whole new slew of nasty field encounters. Plants do not always get top billing in my blog entries, but today two plants have made the grade: Poison Oak and Stinging Nettle.

Poison Oak

Poison oak it isn’t all bad for nature’s non-human critters. It produces berries, which are eaten by a number of different birds including the Wrentit, found throughout our area of California. And its dense viney growth adds a thick layer to the understory in which some birds may nest and small mammals may find protection from predators. However, having had two mild cases of poison oak so far this season I can attest that the bubbled, blistered rash produced by its oil is at best uncomfortable. And at worst, the oil (known as urushiol) from the leaves, stems and berries of this plant cause severe itching rashes, swelling and may even need steroid treatment to get it under control.

Urushiol (which is the same oil found in poison ivy) actually changes the make up of the skin cells it comes in contact with. The body’s immune system then reacts as if these altered cells are a disease and attacks. The itchy rash we get is from the body attacking itself! Over time our bodies become really effective at fighting off this perceived threat and as a result our reactions to the oil only get worse. Washing exposed skin within a couple hours of contact can prevent the rash from developing, but since even a tiny, trace amount of oil is incredibly potent it is difficult to fully detox. And since the effects of contacting the oil may not be felt for several days one’s anxiety has extra time to build, wondering if the tell-tale rash will appear! Getting it on your clothes or boots or backpack is just as problematic. The oils can stay viable for years and the next time you put on your pack or lace up your boots, you might be spreading the oil onto your hands and elsewhere. Yikes!

A 1-2m high barrier of Stinging Nettle

Stinging nettle is another story. There is no waiting to see if symptoms emerge. Brushing against this plant produces an instantly painful sting! The stems are covered in needle-like hairs which when touched, inject a mix of chemicals into its unfortunate victim… often yours truly! Reactions tingle and itch and go numb for anywhere from a few minutes up to 24 hours. I tend to fall into that 24 hour end of things of course, and have to say that it is a strange sensation to have both numb and stinging appendages for that length of time. On the flip side, bees and butterflies love to feed from the flowers, and through trial and error people have found that young nettle shoots can actually be tasty. Cooking young shoots removes the stinging chemicals and the plant can be enjoyed in soups, salads, teas and other dishes. It is even said to improve inflammation problems such as arthritis. Certainly this plant is not without benefits, but a too-close encounter with stinging nettle can definitely ruin your day.

Despite the intense sting, I’ll take nettle over oak any time since the lasting effects are much shorter. And although lacking in the same “icky” factor that ticks possess, both poison oak and stinging nettle are a significant enough bane in the field to warrant making the nasty list!

I'll think I'll be looking for an alternate route around this wall of oak!


One Response

  1. Momchester

    You two sure know how to live a fun life!

    August 15, 2012 at 1:14 pm