It is a concern that so much is being spent on BAER program with such limited success. The methods used in BAER are supposed to be tried and true, and throwing out such a vast mix of seeds without some idea of their viability, a real concern professionally and as a tax payer. Reports as those listed are also typically a warning to professionals as to what is not working, and to stop, reflect before continuing on the same avenue. We had some problems with certain native seed types and stopped trying to spread things that did not work. Also using a seed drill is needed with many native seeds, not just broadcasting by hand or helicopter. Some native seeds like partridge pea are heavy enough though if broadcasting is the selected method. We also saw especially on road projects that the poundage of seed broadcast was too great for emergence of native seed. Using one or more annual seed types in mix was often helpful for quick cover, while some of the native plants are slow to respond, showing up next year unless cover and mulch was too dense. Some BAER projects may use too much mulch, or not provide seed tackifier or use seed drill or hydromulch to keep seed on or in soil. Surface erosion on open bare moderate to steep slopes may be moving seed down the slope. Allelochemicals may also be part of the problem, I do not know. It may be important for botanists to identify which native plant species are commonly found together to ensure compatibility. Some native species may also prefer certain soil types, another potential for stratifying their use.

This post raises several interesting questions:

1) I wonder how much allelopathy contributed to the competitive exclusion (or other recruitment failure) of many planted species. In any case, it is indeed common for many seeded species to not successfully establish.

2) I think we are setting too high a standard for "success", when we say that every seeded species that does not establish is a restoration "failure". I think it is common to add species to a seed mix to maximize the chances that some good diversity is established, not that every species will. But again, I agree that restorationists are often disappointed with how few species establish, and consider this a problem.

3) Aggregated seeding (including "strip seeding") is indeed being explored as means to increase restoration success of subordinate plant species. See:

Porensky LM, Vaughn KJ, Young TP (2012) Can initial intraspecific spatial

aggregation increase multi-year diversity by creating temporal priority?

Ecological Applications 22:927–936

Yurkonis KA, McKenna TP (2014) Aggregating species at seeding may increase

initial diversity during grassland reconstruction. Ecological Restoration

32:275–281.

Although these methods have shown some short-term benefits, their long-term benefits are not clear. See:

Young DN, Porensky LM, Wolf K, Fick S, Young TP (2015) Burning reveals

cryptic plant diversity and promotes coexistence in a California prairie

restoration experiment. Ecosphere 6:81

Young, T.P., K.L. Stuble, K.L., J.A. Balachowski, and C.M. Werner. 2017. Using priority effects to manipulate competitive relationships in restoration. Restoration Ecology 25:S114–S123.

Dear Truman, Glad to hear from you.

By sowing tens of thousands of pounds of seed mixes each year and never testing one species' allelochemical effects vs. another, is like mixing up swimming pool-sized batches of chemicals together, without doing any checking on a test-tube sized scale, to see if they might explode or react badly with each other?

I build one square-foot boxes, 4 inches deep, and fill them with the top 3 inches of soil from a future project site. Then, sow two seed species together--And when you add one gram of seed to the box, that equals a sowing rate of one pound per acre when you sow seeds for the project.

Then, you could build many boxes, to test mixes of two seeds together at several different rates, to see if you can find a happy balance between the two? Or, maybe one species will always knock out another, no matter how small a percentage is in the mix.

For example, you could have a mix, containing 98% one species and only 2% of a second species by weight, and the 2%er can knock out the first species, because of the stronger allelochemicals that it produces.

This is a good method to find new natural herbicides, to eventually replace Roundup! This is finding new weed-antibiotics on a macro-scale.

following

Hiba Riyadh Jameel--Please share and add your answer again, because it did not come up here.

This question has the perfect timing, because a report that came out today from the USDA, NRCS at https://www.nrcs.usda.gov/wps/portal/nrcs/detail/plantmaterials/home/?cid=NRCSEPRD1435909

"How Seeding Rates Can affect Species Composition in Pollinator Plantings" of a mix of ten different seeds----

Forbs and species composition of the seed mix. Asclepius incarnata 1%, Asclepius syriaca-Common Milkweed 2%, Asclepias tuberosa-Butterfly Milkweed 1%, Aster novae‐angliae- New England Aster 15%, Echinacea purpurea- Purple Coneflower 12%, Eryngium yuccifolium- Rattlesnake Master 12%, Heliopsis helianthoides- Oxeye False Sunflower 12%, Monarda fistulosa-Wild Bergamot 15%, Rudbeckia hirta-Blackeyed Susan 15%, and Solidago rigida-Stiff Goldenrod 15% .

You see that except for the milkweed seeds, the other seven seeds are more or less in equal amounts. Then, the article shows the results, where the Blackeyed Susan, Oxeye False Sunflower, Purple Coneflower, and Wild Bergamot had the stronger allelochemicals to wipe out everyone else, image attached. And one of the "zero" and two of the close to zero results were from the most expensive components of that seed mix, the two milkweeds currently going for $160-500 a pound or more, and the New England Aster for $320 a pound or more if you need local ecotype seeds!

That report is showing that with a bad seed mix with the different species fighting each other, the stronger allelochemical will always win over the weaker ones, so why waste $160-500 a pound for seeds, that will never have a chance to win that fight?

This is an interesting idea. Can I ask for the citation of the USGS David Pilliod report in 2017 that you mention in the question? Is this report available to the public?

Article= Article Seventy-Five Years of Vegetation Treatments on Public Rangel...

You and your other researchers, I welcome any answers or comments on my other related questions, that I put together for Federal land managers to ponder--

-- 8 REVEG TESTS for native seeding projects? --https://www.researchgate.net/post/Look_at_my_eight_vegetation_and_soil_tests_I_use_in_the_arid_Western_USA

-- ONLY SOW LOCAL ECOTYPE SEEDS? -- https://www.researchgate.net/post/STARTING_NOW_do_state_and_Federal_governments_planet-wide_need_to_start_only_sowing_LOCAL_NATIVE_SEEDS_in_wild_lands_and_along_roadsides

-- IS CHEATGRASS, NOT INVASIVE? -- https://www.researchgate.net/post/CHEATGRASS--Is_it_really_an_invasive_plant_or_does_it_only_grow_in_soils_that_grazing_lowered_the_soil_nutrients_below_threshold_needed_by_natives

-- NATIVE PLANT SOIL NUTRIENT THRESHOLDS? -- https://www.researchgate.net/post/Soil_nutrient_and_organic_matter_thresholds_for_native_plants_any_research

See also:

Wilkerson, M.L., K.L. Ward, N.M. Williams, K.S. Ullmann, and T.P. Young. 2014. Diminishing returns from higher density restoration seedings suggest tradeoffs in pollinator seed mixes. Restoration Ecology 22:782-789.

Truman--so when you sowed the seed mixes for your paper, did you observe them fighting each other, like the above chart?

As far as you know, is anyone sowing two species together at a time, and measure the allelochemical effect of one against the other?

I have, and been able to rate that interaction on a scale from 1 to 100, with a plant on the "1" scale, having the weakest allelochemical effect.

So if anyone reading this question, has put two plant together, to see who can beat whomever, would be very interested in your answers.

I am doing trials of individual species in Colorado and Kansas.

JUNE 2020 - A seemingly positive report from USFWS "Using Local Seed to Save the Sage"...at https://www.fws.gov/cno/newsroom/Featured/2020/Using_Local_Seeds/

BUT in 2020 with 400 Federal employees and academic researchers getting paid $70 million a year to figure out how to sow natives after Great Basin cheatgrass fires?...Then, the picture of the single squirreltail seedling the resulted from the 2019 native seed mix planting after the Rebel Creek fire... that does not look good at all, when that lone native grass plant is surrounded by cheatgrass seedlings extending to the horizon?

Should we expect better results in 2020, or is the photograph... indicating that we are satisfied when we produce a lone native plant surrounded by cheatgrass, and call it a day?