Saving the Soil: Target Date 2000
The rebirth of soil conservation in Illinois
This the fourth part of the six-article series that appeared in Illinois Issues magazine between September 1981 and February 1982 and was later published as 48-page booklet titled Breadbasket or Dustbowl. (See Publications above.) The topic this month was soil conservation, an old body of techniques that found new relevance in the 1970s. Most Illinois grain farmers, it turned, did gradually begin to conserve topsoils—not by farming less intensively, but by farming more efficiently.
The series was another of that magazine’s examinations of pressing environmental issues, in this case funded in large part by The Joyce Foundation, with the assistance of the Illinois Department of Agriculture's Division of Natural Resources.
For other articles in the series, see "Breadbasket or Dustbowl" on the Farms & farming page.
Illinois Issues introduction: Over the past half century, an alphabet soup of agencies has been working on erosion projects, yet soil loss continues. Illinois’s various approaches to solving the erosion problem are explored in this fourth of six articles on soil conservation funded by The Joyce Foundation
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Illinois farms are losing soil at rates unprecedented since the Depression—11.7 tons per acre annually, according to the most recent estimate. But it is not just soil that has washed away. Dollars are disappearing too, millions of dollars that have been spent in Illinois in the last 45 years by farmers and farm agencies to stop erosion.
Why? Soil conservation has been an official concern of both the U.S. Department of Agriculture (USDA) and the State of Illinois since the 1930s, and a sizable bureaucracy has sprouted up to deal with it. A recent USDA review found 34 separate programs offering some kind of erosion aid; if initials were edible, America could indeed feed the world. In addition to the RCWP, the FWPCA and their kin, the list includes:
1. U.S. Agriculture Stabilization and Conservation Service (ASCS). Founded in the early 1930s, the agency now known as ASCS is the conduit through which such federal farm aid as price supports is funneled to farmers. ASCS maintains a state office which oversees a network or more than 400 employees housed in 99 local offices. Staffed by a director and support staff, the local offices are advised by three-person elected committees which represent farmers in each of the state's 102 counties. It is ASCS which administers USDA's Agricultural Conservation Program (ACP) which has supplied U.S. farmers with more than $8 billion in cost-sharing payments for conservation improvements since 1936.
2. U.S. Soil Conservation Service (SCS). SCS was founded in 1935 in response to the disaster of the Dust Bowl. SCS provides technical assistance to individual farmers, to local ASCS offices as part of the latter's ACP work, to planning commissions and county boards, as well as functioning as what one SCS employee calls the "right arm" of local soil and water conservation districts (see below). Like ASCS, SCS is a USDA agency, and also like ASCS it is organized basically on a county basis. Local SCS offices include a district conservationist and in many cases a soil conservation technician as well, both of whom are advised by a state staff of experts (headquartered in Champaign) in the fields of agronomy, engineering, biology and so on.
3. Soil and Water Conservation Districts (SWCDs). Like the SCS and ASCS, the SWCDs date from the '30s. There are 98 in Illinois which cover all 102 counties. They are independent entities, established by referendum and governed by five-person elected boards, and they provide the formal bureaucratic link between local farmers and agencies such as SCS. They are funded largely by the Illinois Department of Agriculture (IDA), although a few receive support from their county governments; IDA money presently supplies roughly one staff person for every three districts in the state.
4. Cooperative Extension Service (CES). If it is the main business of ASCS to hand out money and that of SCS to hand out advice, it is the main business of CES to hand out information. The Extension Service was founded in 1914 and is funded (as its name implies) by federal (USDA), state (University of Illinois) and local sources which account for 40 percent, 50 percent, and 10 percent of its budget, respectively. There is a CES office for each county (although some small counties share facilities) which together employ more than 400 professional field staff plus another 500-600 support staff. The field staff is augmented by roughly 150 people based at the UI who hold professorial appointments in various disciplines and who function as what one CES official describes as "itinerant teachers who train field staff, prepare brochures, etc. CES' mandate is broader than either ASCS or SCS, since its clientele includes suburban tomato gardeners as well as farmers, and its county offices often include advisers in horticulture, nutrition and home economics as well as agriculture. CES is to the up-to-date farmer what party telephone lines used to be to gossips.
ASCS, SCS, CES and the SWCDs are hardly the only agencies combatting erosion. The state's Department of Conservation is involved, as is the U.S. Forestry Service. State and federal Environmental Protection Agencies (IEPA and USEPA) are active too, as is the Farmers Home Administration (FmHA). AH of these governmental units fund, review or otherwise have a hand in such USEPA funded programs as the Rural Clean Water Program (RCWP). Soil erosion clearly has not lacked official attention. But erosion continues anyway. Why?
In the case of erosion from farms, the answer may be summarized in two words: "voluntary" and "incentives."
Farmers as a group are notoriously jealous of their independence, and the administrative structures of farm programs of every kind have been built to accommodate their clientele's affection for local control and their abhorrence of regulation. The voluntary nature of erosion programs made participation a function of economics rather than ecology. To farmers pushed onto the thinnest of profit margins by increased costs for fuel, fertilizers, equipment and loans, erosion control was simply unaffordable. Specialists from the SCS the CES and other agencies had complained for years about the wastage of Illinois topsoil, but their warnings were lost in a clatter of combines rushing to harvest enough corn to meet the next bank payment.
In 1977, succumbing to pressure from the Association of Illinois Soil and Water Conservation Districts, the General Assembly had amended the state's Soil and Water Conservation District Act to mandate IDA to devise a set of erosion and sediment control guidelines which could be used by SWCDs to model local soil loss standards. However, it was not a farm agency but the U.S. Environmental Protection Agency (USEPA) which first transformed farm erosion from merely another program into an issue in Illinois. Section 208 of the 1972 federal Water Pollution Control Act required that Illinois develop a water quality management plan to control pollutants entering water from so-called "non-point" sources such as farm fields. Consequently, the Illinois EPA (IEPA) in 1977 established a Task Force on Agricultural Non-Point Sources of Pollution to identify causes and cures for farm-related pollution, including sediment. (See "Ag Task Force plans water cleanup," Wesley S. Seitz, Illinois Issues, June 1978.)
The "208 process" in Illinois became in effect a statewide seminar on the subject of farm pollution, especially pollution caused by erosion. Two years of hearings, studies, debate and revision involving virtually all factions of the state's agriculture and environmental communities resulted in a 384-page report which summarized (with modest revision by IEPA) the views of the largely pro-farming task force. In its final form the 208 plan pegged sediment as the gravest threat to water quality in Illinois, and named farm erosion as its principal source. It recommended that soil losses on all Illinois farmland be reduced to the so-called "T" level of no more than five tons per acre per year (the rate of loss at which soil theoretically can be replaced by natural process of soil-building) by the year 2000. It made the Illinois Department of Agriculture (IDA) responsible for an erosion control program which would meet this deadline, and charged IDA to develop state erosion guidelines which would then be used by SWCDs to draft specific erosion standards based on local soil types and terrain—in effect adopting the state's fledging erosion control program. Consistent with the state's program, the 208 plan did not propose any real civil or criminal penalties for farmers who fail to comply with the new guidelines, but instead endorsed a series of public hearings as a sort of trial by embarrassment. It did propose a bushel basket of incentives—tax breaks, expanded ASCS cost-sharing programs, low-interest loans—to farmers who installed any of the approved "best management practices" (BMPs) on their farms. Finally, it proposed sizable expansions of staffs of SCS and CES.
Even before the final version of the 208 plan was approved by the USEPA in the fall of 1979, nonfarm critics had complained about the proposed program. They said it was too leisurely and too lenient, and claimed that agriculture was the only industry in Illinois which set its own pollution rules. Farm interests candidly admit that they agreed to even the modest strictures of the 208 plans because they felt the need to demonstrate a commitment to erosion control sufficiently enthusiastic to stave off mandatory regulation by USEPA, which Illinois farmers have come to regard as the quintessential meddling bureaucracy.
Is this to say that the 208 process accomplished nothing in Illinois? No. The data thus amassed, though controversial in some respects, amounts to the fullest statement so far made of the erosion problem in Illinois. More importantly, 208 forced many farmers to confront a problem they'd ignored too long. If 208 left them still unenthusiastic about controlling erosion, at least they acknowledged for the first time that erosion had to be controlled.
Still, the 208 plan merely diagnosed the disease. It was left to IDA to apply a cure. The IDA guidelines mandated in 1977 were adopted in the spring of 1980 after a series of hearings; although they differ in detail from those set forth in the 208 plan, the ultimate goal of each—reducing soil losses from all Illinois farmland to "T" levels or below by 2000—remains the same.
The state's program also offers farmers incentives in the form of $500,000 in fiscal year 1981 to finance a state cost-sharing program to encourage farmers to switch to soil-saving conservation tillage systems (see box on page 19). Payments to farmers ranged from $10 to $25 per acre, depending on how much protective crop residue was let atop the soil after spring planting. A total of 863 farmers participated, with encouraging results; IDA reports that average annual soil savings on the 26,000-plus acres treated was 14.2 tons per acre.
Those 26,000 acres, unfortunately, comprise only 1/400 of the Illinois farmland on which soil losses currently exceed recommended "T" levels. Jim Frank, who as IEPA's agricultural adviser chaired the 208 ag task force, now runs the state erosion control program as part of his duties at IDA's new division of natural resources. In a speech last spring, Frank said, "The program at this time is not an enforceable program. It has some 'peer pressure' teeth in it—false teeth if you will."
In his speech, Frank also said, "It remains to be seen whether a program of voluntary education and incentives can motivate farmers to do what they know they should be doing but can't afford to do." Nearly all the BMPs cataloged in the 208 plan (the same ones, incidentally, that appear in SCS handbooks and CES brochures and ACP guidelines), cost farmers money in either cash outlays or lost production. Recognizing this, and recognizing that a voluntary program without incentives is like a mandatory program without penalties, both the 208 program and the state's erosion program stipulate that cost-sharing money be made available to farmers. But although the 208 planners recommended a first-year budget for the state cost-sharing program of $5 million, it actually received only 1/10 of that amount. As a result money was available to only 48 of the state's 98 SWCDs, and of those 48, no fewer than 46 had requests from farmers for more funds than were available. Worse, IDA's request for $356,000 to continue the program in fiscal 1982 was eliminated altogether during Gov. James R. Thompson's budget trimming.
State grants to SWCDs totaling $1.55 million were left intact for fiscal 1982. That money was used to hire 36 local staff people to help in the drafting of the new local erosion standards, administer the state's cost-sharing program and so on. But that gives the state only one new staff member for every three SWCDs, a staffing level Frank believes is only half as large as will be required if the state is to reach its "T" level goal by 2000. Agriculture accounts for approximately 20 percent of Illinois’s gross state product, yet IDA programs to conserve the soil on which agriculture depends accounted for 0.0005 percent of the state budget—about 10 cents per acre of farmland per year.
Federal funding is scarcely more plentiful. In fiscal 1981, Illinois ASCS's ACP budget came to nearly $6.5 million. (This counts the ASCS share only; farmers contribute from 60 percent to 80 percent of project costs.) This is down from the $6.9 million allocated per year in the late 1970s, even though demand for ACP funds has exceeded supply for years in Illinois, where some counties routinely receive requests for up to four times their county's allocation.
Gib Fricke, director of the Illinois ASCS state office, describes the 2000 "T" level deadline as "very ambitious" and worries that without what he calls "massive infusions" of federal cost-sharing money the state will not be able to reach it. ASCS staff estimate that the ACP alone needs from $4 to $6 million in new money just to meet current demand; the shortfall in erosion control funding from all sources statewide has been estimated to be anywhere from $8 to $11 million a year.
The budget squeeze may prove to have salutary effects on the erosion planning process, however, if only because it is forcing agencies to be more discriminating about which conservation projects they fund.
Farming's next revolution
The technology of erosion control is neither new nor particularly complicated. One can plant something on the soil to protect it from raindrops (vegetative covers), or flatten out slopes to keep it from running off (terraces), or farm so as to leave more of each year's crop residue behind as a sort of umbrella (any of the various conservation tillage systems), or catch sediment before it leaves the farm (ponds and catch basins), or impede the natural flow of water (contour plowing or strip cropping).
All BMPs are not created equal, however. The USDA reports that the average cost per ton of soil saved on land eroding at an annual rate of 11-12 tons per acre varies widely depending on the erosion control method used to save it. Both state and national surveys show that terracing is among the most expensive conservation options, costing five times as much as conservation tillage per ton of soil saved. (Data from the first year of IDA's erosion control program showed a cost per ton of $1.22 with conservation tillage, compared to a cost of terracing of from $6 to $12 per ton.)
In the past, agencies "targeted" conservation funds by waiting until a farmer came in the door with a request for money, with predictable results. A 1980 USDA program review discovered that 52 percent of the 24,000 erosion projects paid for in part with ACP funds over the years nationwide had been installed on land eroding at rates less than five tons per year, as farmers apparently sought to maximize the return on their share of the costs by installing them on their best land.
No longer. ASCS is being much pickier, according to Gib Fricke. So is the state; this summer Illinois’s SWCDs were asked by IDA to identify those areas in which erosion was most severe or where BMPs would have the maximum effect (for example, in a lake watershed) so that money could be targeted at those areas. There are political risks in such a reversal of policy; the Illinois Farm Bureau, for instance, has warned that frictions might arise if one region of the state receives what appears to be a disproportionate share of conservation money. But the environmental risks of not changing old habits are probably riskier.
Indeed, the last few years have seen a reversal of many agency policies in Illinois. The state and federal farm agencies involved in erosion planning in Illinois admit that in the not-distant past they engaged in turf battles, and not just against sediment. Today, says ASCS' Fricke, "There is solidarity and understanding of the problem at the leadership level in Illinois." Judging from attendance at conservation seminars and the number of requests for money and information directed to agencies, there is an epidemic of interest in conservation. Yet farm agencies note that the crowds tend to be made up of the same people. Understanding at the leadership level, says Fricke, "hasn't filtered down to the agriculture community."
There are indications of a significant shift toward new soil-saving farming methods, but it is too soon to say that Illinois farmers as a group have embraced the new conservation ethic. This is not to say, however, that they haven't embraced conservation. The question is: What are they trying most to conserve? In 1975 the Illinois Division of Energy of the now-defunct Illinois Department of Business and Economic Development surveyed farmers and found that more than 45 percent of them had changed tillage practices since 1970, generally by switching to the less disruptive chisel plow. But that survey also revealed that farmers made such changes mostly to save fuel, not topsoil. The number of farmers converting to less intensive cultivation systems has increased further since 1975, but state farm officials agree that cost, not conservation, is the motive. This raises the possibility that farmers will switch back to old methods if the price of fuel drops, although Jim Frank believes that once farmers see the other benefits of the new tillage systems (such as improved water retention) they'll stick to the new ways.
Conservation tillage promises to be to the 1980s what contour plowing was in the '30s, the central tenet of a new conservation orthodoxy. It is catching on because, unlike most other BMPs it offers a relatively low-cost way to cut soil losses without sacrifices in productivity. Robert Walker of the Cooperative Extension Service (who also chaired the 208 ag task force's subcommittee on soil erosion) estimates that perhaps half the cropland in Illinois that is losing soil could be adequately treated by some form of conservation tillage without significant loss in farm income.
But what about the other half? Walker thinks that terraces, or terraces plus conservation tillage, might suffice, assuming money is available to pay for them. On the state's most erosive acres, however, that won't be enough. These acres simply cannot be farmed for row crops without unacceptable soil loss. The only sure cure is to take them out of production.
The trouble is that there are few attractive economic alternatives to row crop production. Wheat earns less than corn or soybeans, there is little cash market for hay, and few farmers keep cattle that might feed on forage crops because the beef market is depressed. The 208 plan suggests the purchase by SWCDs of "cropping rights" to the estimated 825,000 acres of incurably eroding land. Under such a plan owners would be forbidden to plant crops but instead would plant pasture, forage or forest crops in return for cash payments in lieu of income thus lost. But money for such a scheme is not likely to be available soon.
The elaborate and expensive package of cost-sharing and tax incentives strikes some observers as tantamount to bribery; as Robert Walker admits, "That's a way to buy a program." But traditionally the cost of lost soil has not been computed in farmers' profit-and-loss statements. Adding it in now, in an era of escalating production costs and static commodity prices, threatens to tip farm balances into the red. Frank Schone of the ASCS state office asks, "Farmers complain about the cost of controlling erosion. What about the cost to the farmer of not controlling erosion? How much is that soil worth to him?" The answer in the case of farms built on erodable land, sadly, may be more than he can afford to pay. As economist Steve Kraft of Southern Illinois University at Carbondale confirms, "Forced soil erosion guidelines may change the economic viability of individual farms or whole farm regions, especially marginal farms such as those in southern Illinois. Nobody is looking at this."
Given the economic restraints, can the 2000 soil loss goal be reached in Illinois? Gib Fricke of the state ASCS office describes that goal as "very ambitious." Jim Frank agrees, explaining that continued expansion of row crop acreage will tend to cancel out any improvements in per acre soil losses on land already being farmed, so that the overall annual soil loss statewide may remain at or near the present 188 million tons. Says Frank, "It's a bigger enemy every day."
Other funding schemes will have to be found if traditional cost-sharing funding continues to evaporate. Sen. Jerome Joyce (D., Bradley) sponsored a bill in the 82d General Assembly reducing the local property taxes of farmers who plant protective vegetative strips around their fields; the bill passed the Senate but died in House committee, although it is expected to reappear next session. It has even been suggested that Illinois may someday levy a severance tax on farm products similar to the taxes levied by energy exporting states, to pay for repairs to the land damaged by the mining of topsoil for grain production.
Produce or perish
To a large extent, of course, erosion is a function of a farming system that requires the intensive cultivation of maximum amounts of land; with profit margins so thin, it's produce or perish. Beginning with the Nixon administration, farmers were urged to all-out production to meet global demand for grain. Little heed was paid to the impact which the subsequent frenzy of planting had on the land, so that during the 1970s erosion and food exports rose together. It was as if the president had urged motorists to drive more during the OPEC oil embargo. The Illinois Farmers Union has proposed a return to the federal set-aside program abandoned in the early '70s as a means to buoy prices by dampening production and (because it is usually marginal land that is taken out of production) simultaneously curbing erosion.
Ultimately, it is the public which will pay for the failure to control soil erosion, in higher food prices, clogged reservoirs and the vitiation of rural economies. Pay now in cost-sharing, farmers say in effect, or pay later. But there is yet no strong constituency for soil conservation because the general public does not understand the costs. "It's not as sexy an issue as child abuse or care for the elderly at budget time," admits Frank.
Part of the problem is that erosion is a long-term threat which requires long-term efforts at solution, and long-term efforts are not things that the state's political system is good at. Frank once suggested to a Downstate mayor that he consider boosting water rates to pay for erosion control in the watershed of his city's water reservoir to prolong its useful life, since stopping sediment upstream is vastly cheaper than dredging it out of a lake downstream. The mayor agreed that would be the intelligent way to deal with the problem, but the voters would not stand for it. "They only look at today," he told Frank, "so I only look at today." ●
Farming's new revolution: conservation tillage
It may prove to be the biggest revolution in Illinois farming since John Deere sold his first self-scouring steel plow. It is called conservation tillage or reduced tillage. It takes several forms: zero tillage (known more familiarly as "no-till"), chisel tillage, strip tillage, till plant, wheel-track planting, plow-plant.
They all save soil. To understand how, it is necessary to understand a little about how conventional tillage systems speed up erosion. Under the cultivation practice traditional to Illinois, a moldboard plow is dragged across a field (sometimes in the spring, more often in the fall after harvest). The plow cuts and lifts several inches of topsoil, turning it over and burying the stubble left from the previous season's I crop. These residues eventually decompose, adding organic matter to the soil. Soil is kept loose, and the upending of the surface layers has the further beneficial effect of disrupting the life cycles of certain insect pests like the European corn borer. Later, in the spring, fields are worked again using discs or harrows to break clods and gradually produce a finely-particled seedbed for planting. Later still, during the growing season, further trips are made across fields with cultivators to uproot weeds in plant rows.
The system is very tidy—it is known informally as "clean tillage"—but it leaves topsoil almost perfectly vulnerable to the eroding effects of wind and rain. The heaviest losses occur in the weeks from early spring (when rains are heaviest) until June or July, by which time crops have sprouted their own protective canopy of leaves.
There are other ways to prepare soil for planting, however. A chisel plow (or a heavy disc) may be used instead of the moldboard plow; the chisel plow leaves crop residues largely intact, slicing through them rather than burying them. Or a farmer may choose to not till his land at all. Under the no-till system new crops are planted amidst the residues from the old ones, using a special heavy planter which slices a narrow seed furrow into the sod. Weeds are not plowed under but killed after sprouting by applications of contact herbicides. Because protective residues are left intact, erosion control is vastly enhanced; one study found that moldboard plowing after corn harvest left a scant 4 percent of the soil surface covered, with resulting soil losses of 5.7 tons per acre while no-till left 85 percent of the soil covered, with losses of a meager 0.5 tons. Test results vary somewhat, but the broader results are consistently in favor of no-till. Researchers at Southern Illinois University at Carbondale have even grown crops of soybeans experimentally in live pasture sod, which gives a farmer a bean harvest while leaving winter ground cover in place and supplying some grazing for livestock.
Conservation tillage is not a new idea. But in the past farmers shied away from it, largely out of fear that increased competition from weeds (especially in no-till fields) would reduce yields. But better equipment and herbicides have eliminated many of those problems. Scarcely a week goes by without reports in the farm press testifying to another miracle. A farmer in Loda tries no-till corn after 40 years in the business and gets 150 bushels per acre. Because he cut the number of field trips in half, a farmer near Mattoon saves on fuel costs. A Petersburg farmer uses no-till to bring in 90-bushel corn on hilly land which otherwise would be fit only for pasture.
A series of 10 tillage seminars held by the Cooperative Extension Service last year drew 2,200 farmers statewide. Robert Dickerson of the Soil Conservation Service estimates that in 1980 Illinois farmers used some form of reduced tillage (chiefly chisel plows) on 2.4 million acres of corn and 1.9 million of beans. Also, 218,000 acres of no-till corn were planted in Illinois that year, along with 400,000 acres of no-till beans, and Dickerson expects those figures to go up by 15 percent to 20 percent in 1981.
Conservation tillage is not a panacea, however. Planting in tough sod is tricky, and weed control requires more careful management than farmers who grew up with clean tillage are used to. Conservation tillage may not work at all on poorly drained soils since soil is not exposed to drying winds. Since crop residues shade soil from the sun the soil is slower to warm up in the spring, delaying germination. Residues block absorption of surface-applied herbicides, and as much as 30 percent higher doses are required; in increased concentrations, the herbicides themselves may prove to be pollutants. Although no-till, in particular, saves farmers fuel, it may not save that much energy, since energy is consumed in the manufacture of extra herbicides and fertilizers. Pests can thrive in undisturbed soil layers. (Indeed, some experts have called chisel plowing preferable to no-till since it saves soil nearly as efficiently but requires less chemicals.)
The conservation tillage revolution has many ringleaders. All the major farm agencies are pushing it; a U.S. Soil Conservation Service brochure promises, "You, too, can grow high yielding crops and save soil and water!" In addition, farm chemical and equipment dealers, sensing a new market opening up, have mounted campaigns of their own. Ortho, aware that a switch to no-till can double a farmer's herbicide purchases, bought no-till planters to loan to SWCDs for demonstrations; Deere & Co. in 1980 offered its dealers discounts on conservation tillage equipment made available for such demonstrations. Speaking of the corporate involvement, Robert Dickerson of the state SCS office says, "We'll take all the help we can get."
In spite of such prodding, many farmers remain unconvinced, although their reasons often have little to do with results. For all their image as rugged individualists, farmers tend to follow the pack. A clean field has been the mark of a well-kept farm for a long time, and as the Illinois Farm Bureau weekly, FarmWeek, reported in 1980, many farmers have been slow to switch to what is still often called "trash farming" because of a "concern about what their neighbors would think." And Ron Darden of the Illinois Department of Agriculture recalls, "I asked a farmer once why more farmers don't use zero-till. He said, 'Grain farmers only work 90 to 100 days a year as it is. A grain farmer doesn't feel like he's working if he isn't on a tractor. Conservation tillage reduces the time he spends on that tractor. It makes 'em feel bad, like they're not workin'.'" ●
The Soil Erosion Puzzle: Peering Through The Mud
Solving a puzzle as complicated as soil erosion is difficult. Solving it when one doesn't have all the pieces is doubly hard. The Universal Soil Loss Equation (USLE), for example, is considered reasonably accurate for estimating soil loss from a particular field or slope segment but less accurate when used to estimate soil losses from whole watersheds; in the words of the Illinois Environmental Protection Agency's "208" report for non-point sources, state and county soil loss estimates "should be considered as approximations."
Nor is it clear how much of the soil washed from a given field actually enters downstream water systems. Sediment delivery rates in three Downstate lakes tested ranged from 24 percent to 34 percent, but rates in other lakes may be (quoting 208 again) "quite different." Indeed, some experts like University of Illinois landscape architect Donovan Wilkin argue that it is the unimpeded flow of water, acting violently on stream banks, that is the chief villain.
Also disputed is the rate of soil loss which may be said to be "tolerable." The Soil Conservation Service has defined a maximum annual loss rate of five tons per acre as tolerable. But as biologist Richard Sparks of the Illinois Department of Energy and Natural Resources' State Natural History Survey points out, this contradicts research indicating that soil formation at a rate of five tons per acre can be expected only under ideal soil management conditions, Under more typical conditions soil will be formed at a rate of only 1.5 tons. No one knows for sure, although it is significant that historically soil formation has not kept pace with erosion in Illinois. Sparks concludes, "If 'tolerable' erosion rates established by government agencies exceed actual soil formation rates, we run the risk of eventually 'mining out' the topsoil."
In an attempt to answer such questions, researchers across the state in the last couple of years have begun investigations into areas as diverse as the economics of conservation tillage and sediment runoff from reclaimed mined land. For example, staff at the University of Illinois College of Agriculture have begun a multiyear study of sediment yields from 500 acres of Piatt County land to verify one of the several mathematical models devised to more precisely predict erosion rates. (Noting that all such models are flawed in some way, principal investigator J. K. Mitchell says, "Some day some bright young man will come up with the equation. Not me, though. I won't be in the business that long.")
Others of what might be called research and rescue missions are taking place across the state. At Lake Paradise in Mattoon sediment from a clogged lake bottom is being dredged onto adjacent fields to learn if it is a safe and suitable growing medium. And the Southwestern Illinois Metropolitan and Regional Planning Commission has a program underway in the Metro East St. Louis area under which two watersheds are being monitored to learn the precise relationships between soil loss and water quality.
Nearly as troublesome as the absence of information about soils has been the processing of information which does exist. Soil maps have been made for most counties in Illinois, and work continues on the rest, but they are enormously complex. A new computer system developed at the Argonne National Laboratory near Chicago, however, gives researchers the ability to encode visual data from such maps into digital form, so it can be correlated and presented graphically with other data about geography, ownership and so on. The system has already been used in local 208 planning, and it is possible to use it to estimate more accurately soil losses over large regions using the USLE.
Eventually researchers will learn what needs to be done about soil erosion in Illinois, and how to do it. Until then, erosion's precise cause and effect as well as its cure must remain as clear as mud. ●