Seed mix design for land rehabilitation, reclamation, and restoration has come a long way in the last 30 years. I recall using yellow sweet clover (Melilotus officinalis) in reclamation and road construction projects back in the early 1990’s. Very recently, a client insisted that we incorporate Dutch white clover (Trifolium repens) into a seed mix for a remote mountainous mine site reclamation project, because it was untimely and too difficult to apply for a revision of the existing State-approved reclamation seed mix. Both species are non-native and classified as invasive by most States; and are recognized globally as problematic invasive species. Upon further investigation, I recognized the broader context of this ecological conundrum. The following are examples:
- The potential of using Lavender (Lavandula vera L.) for phytoremediation of soils contaminated with heavy metals (Angelova and others, 2015) appears promising. It has been tested and verified through extensive field applications on mine wastes in Bulgaria and West Virginia. Lavender also produces uncontaminated and valuable crops for use in essential oil and fragrance production. This aggressive native plant from the Mediterranean region, is very hardy, drought tolerant, easy to establish, and is not currently classified as “invasive” in North America.
- Rocky Mountain Bee Plant (Cleome serrulata) has proven to be highly successful in revegetation of drastically disturbed, poorly developed soils of cold and arid regions of the western USA (Curran, 2019). Bee Plant is a native self-sustaining annual forb, with documented success on revegetating barren spoils on several of our projects in southwest Montana. Although the plant has low forage value and can cause nitrate poisoning in grazing animals, it is not listed as invasive by any State. Also, its’ ability to establish on undisturbed soils is rare. Seedling vigor is good with nearly all plants reaching maturity and setting seed the year of establishment.
- Fireweed, (Chamerion angustifolium (L.) holub), a native perennial, literally grows on talus and waste rock piles within our mine sites. We decided that onsite harvest and re-application of fireweed seed for stabilization of steep and rocky micro-sites, was the right thing to do. Upon consultation with our preferred seed distribution company, they offered us $1700 per pound for quantities of this seed. It turns out that fireweed is prolific as a pioneering species on severely burned forest soils and used extensively in revegetation of oil sands tailings in Canada (Pinno, 2014; Omari, 2021). Some detriments to using Fireweed, is that it can rapidly overtake other native plant species, can be very difficult to control if introduced into crops, and numerous references suggest that it is very toxic to humans and many grazing animals.
- Last, but not least, the highly controversial Lupines. Our company is often expected to include Lupines in mine reclamation and range improvement seed mixes. The native varieties are common and prolific on adjacent references sites, and they perform exceptionally well at rapidly colonizing our higher elevation projects. There are at least ten species of lupines in Montana, but the most common are Silky (Lupinus sericeus), Silvery (Lupinus argenteus), and Bigleaf lupine (Lupinus polyphyllus). According to the National Park Service (NPS), Maine’s native Wild Lupine (Lupinus Perennis), has been nearly extirpated by Bigleaf Lupine. Currently, the NPS tries to eradicate infestations of Bigleaf, a native lupine common in western states, from encroachment into Acadia and other NPS parks. Alaska Lupine (Lupinus nootkatensis), native to the Pacific Northwest, has allegedly devasted the ecology of much of Iceland (Kuprian, 2018). It was introduced from Alaska to increase the soil cover and fertilize sandy and gravelly soils. For that purpose, it has been widely used throughout Iceland since the 1980s. Bluebonnet Lupine (Lupinus texensis), a native variety from the southern- and mid-western U.S., and many other of the 100-plus lupine varieties, cause lupinosis, a crippling and often fatal disease in sheep, horses, cattle, and other grazing animals (colostate.edu, 2019).
In conclusion, there is obviously a need to fully consider the unique characteristics of different species and sub-species of forbs we use while performing land improvements. The unanticipated consequences of our actions could be significant.
John Whittingham, Montana Representative, MSC IECA, CPESC, PWS, info@basicbiologicalservices.com Owner, Basic Biological Services LLC, Dillon, Montana, basicbiologicalservices.com