The description "Tightly" is relative to pH and phosphorus content of the soil. The following paper appears to me (so far) to be the most complete study of what phosphate (commonly just called phosphorus in gardening circles) does to glyphosate binding. ------------------------------ Title: Effects of phosphate on the adsorption of glyphosate on three different types of Chinese soils. Published in: J Environ Sci (China). 2005;17(5), pages 711-715. Authors: Wang YJ, Zhou DM, Sun RJ. Authors affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China. Abstract: "Glyphosate (GPS) is a non-selective, post-mergence herbicide that is widely used throughout the world. Due to the similar molecular structures of glyphosate and phosphate, adsorption of glyphosate on soil is easily affected by coexisting phosphate, especially when phosphate is applied at a significant rate in farmland. This paper studied the effects of phosphate on the adsorption of glyphosate on three different types of Chinese soils including two variable charge soils and one permanent charge soil. The results indicated that Freundlich equations used to simulate glyphosate adsorption isotherms gave high correlation coefficients (0.990-0.998) with K values of 2751, 2451 and 166 for the zhuanhong soil(ZH soil, Laterite), red soil(RS, Udic Ferrisol) and Wushan paddy soil (WS soil, Anthrosol), respectively. The more the soil iron and aluminum oxides and clay contained, the more glyphosate adsorbed. The presence of phosphate significantly decreased the adsorption of glyphosate to the soils by competing with glyphosate for adsorption sites of soils. Meanwhile, the effects of phosphate on adsorption of glyphosate on the two variable charge soils were more significant than that on the permanent charge soil. When phosphate and glyphosate were added in the soils in different orders, the adsorption quantities of glyphosate on the soils were different, which followed GPS-soil > GPS-P-soil = GPS-soil-P > P-soil-GPS, meaning a complex interaction occurred among glyphosate, phosphate and the soils." This abstract is presented in technical terms. A quote from the conclusion section of the full paper will probably be clearer. On page 775 in the conclusion section, the following appears that is important in discussing whether glyphosate is available to the roots of a plant from the soil or is too tightly bound: "Phosphate, which has higher affinity to soils than glyphosate, competed with glyphosate for the adsorption site of soils when they coexisted. Applying glyphosate in soil containing higher content of phosate will possibly increase the environmental risk of glyphosate transferring from soil to groundwater and surface water." http://www.ncbi.nlm.nih.gov/pubmed/16312989 Here is a link that might be useful: link for above

Carol, Ann Peck (GardenWeb user name anntn6b) would be the person to ask. She has written the eBook that many of us use as a reference for RRD.

This is a news release from June 2005, from the NJ Audubion Society: For immediate release Contact: Eric Stiles June 15, 2005 (908) 766-5787 ext. 13 Kathleen Bird (609) 392-1181 or (609) 273-7750 Groups Urge Restoration and Protection of NJs Rarest Wildlife Habitats Conservation Partnerships with Private Landowners Essential to Saving Key Grassland Habitats, Critical Species Federal, state and nonprofit conservation officials joined forces today to highlight the importance and process of restoring New JerseyÂs rarest habitats  grasslands and other habitats in early succession such as shrublands. Landowners have an essential role to play in preserving New JerseyÂs most critically endangered habitats and can benefit financially by voluntarily conserving critical natural resources on private pastures and farmland, the experts said. "New JerseyÂs grasslands have reached a critical juncture. Strong, voluntary partnerships are needed to protect these areas and prevent the large number of threatened and endangered species from disappearing from New Jersey," said Eric Stiles, vice president of conservation and stewardship for New Jersey Audubon Society. "Grassland conservation is a private-public partnership, based on financial rewards to willing landowners, and involving state and federal agencies." New Jersey has lost agricultural and grassland habitat at an alarming rate, from nearly 1 million acres in 1972 to less than 850,000 acres in 2001, based on the latest available state data. And in just a six-year period  from 1995 to 2001  nearly 26,000 acres of agricultural lands were lost to development. "Grasslands and other early successional habitat are New JerseyÂs most critically endangered habitats," Stiles said. Eric Schrading, Senior Fish & Wildlife Biologist and Private Lands Coordinator for the U.S. Fish & Wildlife Service based at its New Jersey Field Office in Pleasantville, said, "Much of the land in New Jersey is privately owned, so protection of our essential natural resources depends on partnerships with willing landowners. Agricultural grasslands, which provide shelter, safety and nourishment for grassland birds, are the most rapidly disappearing land type in New Jersey." "Since they lack trees, the agricultural landscapes of pastures and farmland that contain New JerseyÂs grasslands are easier and cheaper to develop and often targeted first by developers," New Jersey AudubonÂs Stiles said at a press conference today at the ecologically important and strikingly beautiful Wallkill River National Wildlife Refuge in the Sussex County community of Sussex. The Wallkill River National Wildlife Refuge was chosen for the event to demonstrate the successful grassland restoration and management practices occurring there. The refuge is a gem in an expansive, historically agricultural area of the northwestern part of New Jersey. Nearby Wantage and Vernon townships in Sussex County and Pohatcong in Warren County feature enormous tracts of grasslands hosting critical bird species whose populations are in jeopardy. Critical habitat for grassland dependent species, also found throughout other areas of New Jersey, has been rapidly disappearing due to development. As habitat dwindles, bird and other species decline. The U.S. Department of AgricultureÂs Natural Resources Conservation Service, the U.S. Fish & Wildlife Service and the New Jersey Department of Environmental ProtectionÂs Endangered and Nongame Species Program are providing financial and other incentives to farmers to restore native habitat and to manage their lands to benefit wildlife. New Jersey Audubon Society, the stateÂs oldest and most respected conservation organization, is advocating grassland preservation and restoration of native vegetation that provides habitat for species that are listed as threatened, endangered or of special concern by the state. Landowners can learn about how they can manage property of any size to benefit wildlife through a new handbook, "New Jersey Audubon SocietyÂs Guide to Incentive Programs for New Jersey Landowners." It is a clearinghouse for information about state and federal programs that provide financial and technical assistance. The guide is available on NJ AudubonÂs Web site at: www.njaudubon.org/Conservation or by calling (908) 766-5787. "State and federal habitat management programs provide a win-win situation for farmers and for natural resources," said Kim Korth, a biologist who oversees the Landowner Incentive Program under the state Department of Environmental ProtectionÂs Endangered and Nongame Species Program. There has been a dramatic loss of grassland and other early successional habitats statewide and major impacts to the species that use them. Forty percent of the birds on New JerseyÂs endangered list rely on grasslands, while almost 30 percent of birds listed as endangered, threatened or of special concern are considered early successional species. Over 85 percent of New JerseyÂs listed insects including butterflies rely on grassland and early successional habitat. New Jersey still contains important grassland and early successional habitat including habitat for the largest single populations of frosted elfin and arogos skipper globally," said Korth, referring to species of butterflies. Established native vegetation such as Indian grass, little bluestem, big bluestem and switchgrass have many benefits, including needing less treatment, such as fertilizer and lime, than traditional grasses. "Tall native grasses have provided habitat to grasshopper sparrows, bobolinks, northern harriers, upland sandpipers and more," said Tim Dunne, biologist with the U.S. Department of AgricultureÂs Natural Resources Conservation Service based in Clinton. Most farmers traditional hay and pasture crops are cool-season grasses and legumes such as timothy hay, rye grass, orchard grass and alfalfa. These get their first cutting in late May or early June  timing that corresponds to the peak nesting season for grassland birds. As a result, breeding bird pairs selecting these hayfields are doomed to fail. The result is the destruction of habitat and further declines in both the number of individual birds and the number of species. Habitat management to benefit wildlife includes farmers creating buffers, filter strips and other areas that are undisturbed during the nesting season, said Dunne. NJ AudubonÂs Eric Stiles added, "Without adequate protection, creation and management of their nesting habitats, grassland birds will continue to decline in New Jersey until they are locally extinct. Federal and state incentive programs offer some hope. "Grasslands are top priorities for these programs. But in order to succeed best, these programs must focus on areas where converting to grasslands is the most feasible. ThatÂs not all. In addition, effective management is needed on lands owned by nonprofit conservation organizations and by federal, state, county and municipal agencies in regions where grassland management should be a top priority," said Stiles. The Wallkill River National Wildlife Refuge was established by an act of Congress in 1990. It hosts more than 200 species of birds, as well as a variety of plants and other animals. While the refuge was created primarily to provide habitat protection for migratory waterfowl that inhabit its wetlands, it manages native, warm-season grasslands. They provide critical habitat for important threatened and endangered bird species including bobolinks and savannah sparrows that inhabit the uplands. If you Google "grassland" and "endangered" or "Threatened" you should find lots.

@Paul Zimmerman Is there a way to give directly to a 501c3? I'm happy to give something. but would rather not give a cut to GoFundMe while also not getting a tax deduction. As a Tennessean I would be happy to make a donation through the University of Tennessee--and let the research benefit from all the money--but I'm not sure how to do that...