The Invasion of the Orchids

Written by Jeremy Smith and Joan Martin, DRBIPA Members & Langley Field Naturalists – August 20, 2019

It’s the invasion of the orchids! Well, not quite, but there is an introduced orchid spreading across our region that acts like a weed. Its name is the Broad Leaved Helleborine or Epipactis Helleborine. One of the members of Derby Reach Brae Island Parks Association spotted it on the Tavistock Trail on Brae Island, where it appears to be spreading.

This is an unassuming little plant, 35 – 50 cm tall, with a single stalk and purple flowers along the upper stem. When you bend down and look closely, you see they are indeed orchid flowers. It is classed as an invasive alien in parts of the United States. It will probably become a lot more common in our area over the next few years. It is very adaptable, growing in disturbed areas such as gardens and roadsides, as well as more natural forested areas.

Don’t let its small size fool you though, there is a lot going on with this plant. Firstly, all orchids need an association with a symbiotic fungus, at least when they are seedlings. The seeds are almost as fine as dust and the fungus helps this tiny, tiny plant extract nutrients and water from the environment. Many orchids maintain this mycorrhizal symbiosis all their lives. Secondly, the sweet nectar contains small amounts of opioids. Yes indeed, insects respond to opioids. This neurochemical response may be 100 million years old or more. The wasps and other hymenoptera insects that pollinate these flowers may have been addicted for a long, long time!