Rare Plants: What’s It Good For?

Do you have a minute?

Where should I start? I was driving in to meet Jeremy Lundholm’s class a couple of years ago as I’d agreed to give a talk on rare plants, specifically, the Endangered Eastern Mountain Avens. As I drove, I lost confidence..why should these students care about rare plants? Why have I been drawn to study rare plants for much of my research and conservation life?

Eastern Mountain Avens-Endangered. Persists vegetatively in low nutrient, moderate pH, cool wetlands with near surface watertable. Regenerates after seed dispersal by ….unknown….in disturbances of Sphagnum lawn by fire, ungulates, all-terrain vehicles.

Plymouth Gentian-Endangered. Vegetative growth in infertile wetlands, large seasonal water-level fluctuations, ice-scour disturbances. Regenerates after seed flotation in liverwort in Twigrush nurseries

The last time I left Brier Island, I got talking on the ferry to a couple of guys who had real jobs as electricians. We talked about our day–rewiring  and bog restoration to rescue the Endangered Avens–and one  guy asked, “what’s it good for?”

As I go over the plants in my career..Plymouth Gentian, Long’s Bulrush, Golden Paintbrush, Early Coralroot Orchid, Southern Twayblade, Eastern Mountain Avens.. a pattern emerges. Each rare species is an indicator, a landscape specialist, a green light that the ecosystem was working as it should be. The Coastal Plain flora was first in my career. Paul Keddy had maintained that this flora required infertile wetlands and then 20 years later, leaky mink farms in the upper watershed of the Tusket demonstrated how important the rare plants were: nutrient inputs to the river allowed blue green bacteria to bloom, let robust exotics like Reed Canary root in the water column which threatened to competitively displace the slow-growing, small, evergreen rosettes of the beautiful Plymouth Gentian.

Rare plants are useful sentinels of ecosystem processes. They are the green lights indicating all is well and they are the most sensitive to ecosystem alteration. This sentinel thesis is put forward in an upcoming paper in Rhodora ( SENTINEL ).

Southern Twayblade, Neottia bifolia, S3 Rare. Requires mycorrhizal connections to basidiomycetes and black spruce maintained in cool moist lawn of Sphagnum under spruce swamp canopy. This mycotrophic orchid was only plant extirpated after swamp disturbance (see SENTINEL)