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Out There: Touch-Me-Not

There are some plants that are very sensitive to being touched
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Policeman’s Helmet (Impatiens glandulifera) is the largest touch-me-not found in the area. (Photo by Ed McMackin)

By Ed McMackin, biologist by profession and naturalist by nature

There are plants that are sensitive to being touched. One is the sensitive plant (Mimosa pudica), which when touched, folds up, and may open back up in a couple of hours, or may not look normal again until the next day. The venus fly-trap usually it goes into action when a fly or other small insect lands on a sticky part of the plant. It then closes its leaves, trapping the insect inside. The sticky surface then “digests” the critter. Many plants and some other life forms, that zoologists and botanists are not sure whether they are plant or animal, also have mechanical aspects.

One other example is the squirting cucumber. That plant I have personally never met, so I will leave that one to you to investigate. It is not always a matter of touch me and I’ll eat you, or I will squirt, or I’ll wither, but in some cases it is, “If you touch me I will go ballistic!” Another group of plants, called “touch-me-nots”, do just that. This small group of plants, of the genus Impatiens, belong to the Balsam family (Balsaminaceae).

The cape jewelweed, touch-me-not, or orange balsam (Impatiens capensis) is found mainly in coastal regions from southern British Columbia, southward through Washington and Oregon. I remember one from southern New Brunswick that grew in a moist ditch along the road, which had gold spots on the petals, hence the name “jewelweed”.

In our local Kootenay Lake region, we have the “spurless touch-me-not”, called as such because the back of the flower is spurless while some of the other species have a spur. Like the others, this smooth succulent is “touchy”. This native jewelweed grows well in damp or wet soil and goes by the name Impatiens ecornuta. The flower is generally a plain yellow-gold in color and about 1 inch (2.5 cm) in length. It has a tubular, trumpet-shaped flower made up five fused petals and a seed pod that bursts open on touching or when the seeds inside have ripened.

This local species of Impatiens doesn’t eat or squirt you but, like our other touch-me-nots, has its own ballistic mechanism that shoots the seeds away from the plant. The pod when mature bursts open and an uneven tension in its covering instantaneously curls the five strands of the pod into tight coils catapulting out the seeds.

This action is also found in more impressive and much larger species of Impatiens found on uncultivated land in the Kootenay Lake region.

This one goes by the name of “Policeman’s Helmet”, (Impatiens glandulifera), that, although it is not an orchid, is also locally, called “Alaskan Orchid”, a bit of a misnomer. It is an introduced Asian ornamental which has become established in uncultivated areas, namely wet ditches and swamps around residential areas. It is also grows naturally in a few gardens, but is not invasive.

It would be difficult to see seed pods in action in late fall unless one were to find some late bloomers. Two areas one could check now or, ideally in August, their blooming time in the south Kootenay Lake area are a ditch along Packing Shed Road in Wynndel and a cat-tail swamp on Helen Road, by the trail in north Creston. There I found them growing any height from three to eight feet tall, with flowers about 1.5 in. (4 cm) in length.

If you find a plant and don’t know what it is, ideally, get a photo and send it to me with a description at anagallis77th@gmail.com. Also if you want to see strictly Kootenay Lake region flowers, log into Eflora BC and enter Ed McMackin in the search bar.

READ MORE: Out There: White-tailed Ptarmigan