Notes on the History of Seeding in Forest Preserve District of Cook County
Stewardship Council Annual Meeting
January 13, 2019
by Stephen Packard
I was asked to summarize what I know about the history of seeding in Cook County Forest Preserve (FP) restoration.
In earlier decades, FP staff bought seed from the cheapest sources. Tree seed may have come from southern Illinois or even commercial sources of European species. For the scenic meadow, play meadows, and other open areas, they planted European pasture grasses, which was all that was available. There was little true ecosystem restoration as it is now known until the influential prairie restoration work of Ray Schulenberg (begun from seed collected along railroads in 1962) and later by Dr. Robert Betz.
The earliest large FP prairie restoration was by Chuck Westcott, director of Crabtree Nature Center. The grass seed came from a company in Nebraska, as that was how people got quantities of grass seed at that time. It was believed that wind-pollinated grasses might not have highly locally adapted genetics. Forb seeds were gathered locally. They called the resulting prairie “Phantom Prairie” to emphasize that it was not the real thing, and the real large prairies were gone.
Many people were influenced by the 650-acre Fermilab prairie restoration, when it was begun in 1974. Seed for that restoration came from spontaneous sources within fifty miles. Prof. Robert Betz of Northeastern Illinois University, who supervised that work, advised the FP on their prairies.
When the North Branch Prairie Project started in 1977, FP staff encouraged us to develop plans with advisors Betz, Schulenberg, Westcott, and others. This work was very different from that done at the Arboretum and Fermilab, in that we were starting with degraded prairie remnants rather than cornfields. Also, since many small prairies were known nearby, we sought to conserve local genetics as much as possible by limiting the seed we gathered to a radius of 15 miles. When our own discoveries and the advice of staff and our mentors inspired us to expand the restoration work to include savannas and woodlands, to our surprise we found it more difficult to locate a full complement of species nearby, so we expanded our range to 25 miles for savanna and woodland species. For difficult to collect species, we gathered what few seeds we could, gave them to the Chicago Botanic Garden to propagate, and distributed the seedlngs to gardens where seed could more easily be gathered.
With the encouragement of the Illinois Nature Preserves Commission, the FP approved restoration projects at Wolf Road Prairie and in the Calumet Region. In both cases, very high quality ecosystems were being lost to brush. The goal was to cut the brush, burn, and let the ecosystem heal itself. So far as I remember, no thought was given to seed in those areas.
FP staff appreciated North Branch type restoration efforts sufficiently to invite The Nature Conservancy to sponsor a similar effort on hundreds of acres at the Poplar Creek preserves in 1989. It seemed daunting to get seed from within 15 miles, and unnecessary, as most acres were former cornfields. So we set the limit at 50 miles. On the other hand, this project included the very high quality Shoe Factory Road Prairie. It was agreed that no seed would be introduced into the high quality prairie. The Poplar Creek Prairie stewards developed an impressive seed collection initiative under the leadership of Diana Granitto. Every attempt was made to get as much seed as possible close to home.
A similar project at Bluff Spring Fen followed similar principles. BSF included some of the highest quality wetland communities in the region. No seed was introduced to them. But seed was sought for the surrounding prairie, savanna, and woodland areas, which were degraded and impoverished.
Some of the biggest FP prairie restorations emerged at the Bartel and Orland Grasslands – funded by and in collaboration with Openlands. In both case, the initial goal of staff and volunteers was to seek seed from within 50 miles. In neither case was high quality prairie part of the project. As knowledge of global climate change was advancing, we began to seek at least some seed from farther south and west (and limit seed from east and north.) In time, what we might call bureaucratic complexities resulted in some people buying seed with less regard to where it originated. Although it had been agreed that the restoration here would not be limited to highly local seed, the Orland Grassland Volunteers did impressive work to find as much seed as possible from nearby, so at least some local genetics would be in the mix.
A major restoration effort for the Spring Creek Preserves was launched in 2003. The goals here included thousands of acres of restored prairie, woodland, and wetland. The seeds plan drew on the plans that by this time had been approved for the North Branch, Poplar Creek, and Orland restorations. In this case, areas were mapped according to how local the seed should be. This effort had the great advantage that Citizens for Conservation had for decades been gathering local seed and multiplying it in restored prairies, woods, and wetlands on their own land. Much of the seed for this work was donated by or gathered in collaboration with Citizens for Conservation.
At Deer Grove, two distinct plans were followed for the two parts of this preserve, as divided by Quentin Road. West of Quentin, restoration for decades used seed from on site. East of Quentin an ambitious restoration was planned jointly by staff of FP and Openlands. In this lower quality section, the restoration was more intensive and required seed purchased from contractors, although, again, the Deer Grove Volunteers sought to contribute as much local seed as possible according to plans modeled after previously approved plans. As always, seed was sought from areas with similar soils, that is, no seed from sand areas going to black soil areas.
In 2016, the “Forest Preserves of Cook County Seed Source Policy and Guidelines” was completed. It’s interesting to compare this document with how seeds guidelines were designed and implemented over the years. For example, the North Branch and similar seeds plans seem to be an example of “Tier 1, Relaxed Local (RL).”
Some key portions of the 2016 Policy include:
In general, large populations (>1,000 genetically distinct individuals) are more likely to be locally adapted to site conditions than small populations (Leimu and Fischer 2008). Moreover, large populations are less susceptible to losing genetic variation due to drift and better retain capacity for responding to environmental change. Although we can make some such generalizations, we know too little about most plant species to say with much precision what the appropriate seed source distance should be. Furthermore, genetic depletion in small populations may dictate that seeds from more distant sources are needed to increase genetic diversity and thus likelihood of survival. More generally, mixing of seed sources may also enhance genetic variation and evolutionary resilience of species (Jones 2013) and could be a strategy for dealing with predicted climate change conditions within a region (Krauss et al. 2013). However, in an attempt to understand the effects of introduced seed, limiting the source to a single large population (e.g., >1,000 individuals) is one advisable approach. The benefit of this approach is to allow documentation of positive or negative effects of augmentation and isolation of the impact of specific source populations. In addition, economic considerations of cost and availability of seed from local versus regional sources often must be balanced with the potential risks of using seed from distant sources. Regardless of source, there are many considerations during the collection of seeds and propagation of plants at new sites or in nurseries that may affect genetic diversity. Appendix 4 outlines best practices for collecting and propagating plant material (Basey et al. 2015).
To ensure that its staff, contractors, partners, and volunteer stewards have the flexibility to address the specific goals of each project while considering genetic concerns, seed availability, and climate change, the FPCC has adopted a tiered approach to selecting seed sources. Three seed source tiers have been defined, based on administrative boundaries and distance from the project site (Figure 1).
APPENDIX 4 Rules for maintaining genetic diversity during the collection and propagation of native plants, taken and modified from Basey et al. (2015).
Identify sources with conditions similar to potential restoration sites.
Collect from sites with large populations.
Leave no genetic stone unturned – strategically collect seeds to ensure broad representation of individuals in the population.
Prevent loss of viable seeds during cleaning.
Use optimal storage conditions.
Diversify seed germination conditions.
Lessen the impacts of plant maintenance.
Minimize unintended hybridization.
Vary timing of seed harvest.
Limit the number of generations grown in production.