We just returned from the National Native Seed Conference in Washington DC. The title is a bit of a misnomer. Most of the attendees were from the western US where federal agencies are the largest landowners and buy millions of pounds of seed for restoration after wildfires, drought and other natural disasters, and for rehabilitation of lands disturbed by mining, invasive species, and other human disturbances. All of the sessions this year related to the National Seed Strategy released in 2015 and formulated to address the need for more and better native seed. Over the next month I’ll try to cover some topics in more detail but here were some of the issues and concepts presented at the conference that captured my attention.
Resilient plant communities will adapt to climate change and resist invasion by non-native species better than degraded ecosystems. But how do we increase resiliency? More diverse seed mixes that represent a variety of plant families: asters, legumes, grasses, sedges, and less common like roseacae. Plant species with varied life cycles: warm season, cool season, annuals, perennials, even shrubs. Plant early successional species like annual sunflower or at a minimum don’t despair if they appear in abundance. Consider the root structure: fibrous, taproots, and rhizomatous.
The seed strategy stresses the importance of seed transfer zones which should help preserve the genetic diversity of individual species. I’m still trying to figure out how this might work in Nebraska. A logical starting point is to source seed by EPA ecoregions or the vegetation communities of Nebraska developed by Robert Kaul and Stephen Rolfsmeier. The vegetation units must be large enough to support several populations of a given species without varying too much in climate or soil conditions. This would be a good project for the Nebraska Native Plant Producers to pursue in cooperation with Game and Parks, USDA NRCS, Nebraska Crop Improvement, and other interested parties.
If genetic diversity is the goal, how do current testing and sampling methods based on commodity crops contribute to that end? Currently not well. No one wants to introduce an invasive weed like Palmer amaranth or cheat grass into a restoration but when an agency buys 1-2 million pounds of native seed some contaminants are probable. Cleaning and testing seed deserve a separate entry in this blog but I learned some crazy things at the conference. I should have known that noxious weed seeds are on a separate list from noxious weeds in each state and some restricted or noxious weed seeds are native like annual sunflower, smooth dock and horsenettle. These will not ruin a restoration or pollinator planting. Another surprise was the revelation that the standard viability test for dormant seed is not very accurate for some species. It underestimated the viability of some Carex (sedge species) by three to six times what actually germinated in a greenhouse study. Yikes!
All in all I enjoyed the conference and returned home with several new/renewed goals. Our niche will continue to be local ecotype seed but we need to expand our acreage and increase the number of wild populations we collect from to expand diversity in our seed plots. I would like to grow some more common but under-represented species like upland sedges and maybe some annuals like prairie ragwort or wild bean.
To be continued and probably edited…