SEEDBED
By Keith Reid
Squeezing more from meagre margins
It appears we're heading into a year in which returns from growing crops aren't going to be as high as we're used to. At times like these, we need to choose where we should best spend our limited resources to produce the best returns.You need to invest in the inputs that will give the greatest return this year, but be mindful that some of choices will have impacts in the future.
But which inputs get the highest priority?
Soil first
When cash is short, look first to the factors that can be
influenced with
minimal cost. Preparing a good seedbed is a matter of skill and
patience
rather than a lot of expensive hardware.
The most frequent mistake farmers make is driving over the field before it is dry enough to carry the traffic. Simply taking a shovel out to the field in spring and making sure the field is dry to the depth of tillage would increase crop yields.
Seed choices
Buy the best seed that you can for your farm: This is definitely
not the
place to cut corners. Look for high yield potential, of course,
but also
look for year-in and year-out
consistency and stress
tolerance.
Don't place too much weight on hybrid performance in 1998, particularly when it comes to choosing long-season hybrids. We may not get an extra 500 heat units next summer.
Spread your risk with a mix of early and midseason hybrids, along with some full-season hybrids to take advantage of a long season if we get it.
Winter is also the time to make sure your planter is working properly, so that you can get the right number of seeds into the ground at the right depth and spacing. Proper operation of the planter is critical to getting a good stand, but too many farmers still just go to the field and drive, without checking to make sure things are working right.
Weed control
While you cannot grow high-yielding crops and weeds in the same
field,
there is a limit to how far weed control costs can be cut. Weed
control is
an input that gives an excellent return if it works, and no
return at all
if it fails.
There are two main approaches to weed control. The first is to apply a broad-spectrum herbicide at full rate to kill whatever weeds might be there. The second is to know the weed populations and apply the lowest rate of the least expensive control method to kill the weeds that are actually going to compete with the crop.
The second approach can provide excellent weed control for a fraction of the cost, but it depends on replacing inputs with management skill. Spraying a rescue herbicide because you mis-identified a weed can wipe out any savings as well as hurt the crop.
Fertilizer
Adequate nutrients are essential for growing a profitable crop of
corn,
but this does not necessarily mean a big fertilizer bill. The
first step is
to take soil samples so you know how much you will need to add to
the soil
- or if you need to add anything at all. With a typical
fertilizer program
for corn costing $50 to $100 per acre, it makes sense to spend $1
an acre
to manage it properly.
Once you have your soil test results, look first at the soil pH. Even if it doesn't hurt the crop directly, acid soil will interfere with the uptake of all the major nutrients. If you need lime, spend money on that first. Aim for the lowest cost per acre: Unless your soil magnesium is low, it doesn't matter whether you use calcitic or dolomitic lime.
The next nutrient to consider is nitrogen. You will not want to cut here: Corn is much more responsive to nitrogen than to any of the other nutrients. At the same time, consider whether you are making full use of on-farm sources of N. Legume plowdown and manure can provide most or all of the nitrogen requirements of the crop. Make sure you are managing these resources for the most efficient utilization.
A soil nitrate test can give you a general idea of whether your crop will need a lot of nitrogen, or a little, even if you don't feel comfortable using the exact recommendations.
Apply phosphorus and potash according to soil test recommendations. You'll get the biggest bang for your buck from banded applications of phosphorus, either with the seed or two inches to the side. Use the source with the lowest cost per unit of nutrient: There are no significant differences in availability of nutrients from the common sources of phosphorus or potassium.
Apply P and K only in amounts that the crop will respond to this year. Leaving out a maintenance application of phosphate or potash will not affect this year's yield at all, although in the long run soil test values will decline.
Unless you know you are deficient in a particular nutrient, leave micronutrients out of the mix. In most cases, they are not required for optimum corn yields.
In many ways, managing crops for least expense means going back
to the
basics of agronomics. These are the things we should do every
year, but
they take on added importance when getting the most out of every
dollar
counts.
Keith Reid is OMAFRA fertility specialist, Walkerton
kreid@omafra.gov.on.ca
back to February 1, 1999 Issue
Phosphorus management pays plenty Tracking subterranean phosphorous movement - and finding an eager young partner - keeps this New York farm milking BY K.O. WILSON Bob and Carol LaTourette's hillside dairy farm in Sydney Center, N.Y., was in danger of going out of business. Phosphorous leaching into nearby streams was considered a pollution hazard. They didn't have the financial wherewithal to make the operation compliant. And they had no children interested in carrying on the operation. But after years of legal battling with New York City, the LaTourette's Vallee Cote Farm received environmental upgrades totaling $100,000, paid for by the city as part of a broad plan to keep phosphorous out of its drinking supply. And a young local man, Scott McClennon, wants to make a go of the operation, which milks 58 Holsteins and raises 32 replacement heifers on 227 acres. The farm sits at the headwaters of streams feeding the Cannonsville Reservoir basin, a major source of New York City's water supply. Elevation is about 750 metres above sea level. The payments came as a blessing for LaTourette, who for years has wanted to implement conservation upgrades but never had the dollars set aside to do it. And they meant McClennon could proceed with his dream of dairying, assisted by additional funding from the U.S.'s Farm Home Administration, where he will apply for a first-time buyer, low-interest loan to complete the farm transition. Phosphorous increases algae blooms in reservoirs, producing odour. Chlorine can be used to kill the blooms, but there's concern over the potentially cancer-causing effects of the byproducts that evolve - tri-halomethanes. One solution is to simply keep phosphorous out. The barnyard at Vallee Cote lies directly adjacent to a tributary of one of the six city-owned reservoirs. Barnyard manure was washing directly into the watercourse. As part of the environmental upgrade, nutrient flow throughout the entire farm was factored into the feeding, planting and manure spreading schedule, and a concrete barnyard pad was constructed. It slopes gradually toward a sediment collection channel containing three screens. These trap the manure not removed by skid steer, and that collection is periodically removed by hand shovel. Soiled rainwater and snow melt - about one metre annually - moves through the screens to a combination of three collection tanks buried downhill from the barnyard. Milkhouse waste is also collected in the tanks, which have 500-, 1,000- and 1,500-gallon capacities. Runoff from here is pumped under the creek, back up the opposite hillside and drains from an above-ground piping system onto the ground. It then sinks into the ground in an area where two stone tanks, much like old wells, have been built, and from there the soiled water leaches into the ground. The system removes the bulk of the immediate pollutant loading. Vallee Cote turns out about 950 tons of straw-laden manure a year. Precisely managing it initiated three years of hillside research. The main corn field, at approximately 20 acres and with a slope of nearly 16 per cent, had edged into a very high annual soil erosion rate of 17 tons per acre, in part due to continuous production of corn for 15 years. Most of the eroded soil settled in the lower fields. Soil there is coarse, loamy glacial till, approximately 50 centimetres deep, on bedrock of sandstone and shale. Planners from Cornell University devised a computer-based phosphorous flow index that looks at soil types ranging from sandy to clay to loamy, as well as gradient, absorption and other ground qualities. The index first predicted that withholding all chemical phosphorous fertilizer would immediately lower LaTourette's corn field from a "very high" risk to a "high" risk pollution category. Related studies showed that even by halting all applications - including manure - phosphorous leaching would decline by only 50 per cent since residue from prior applications remains in the soil. Studies are currently underway to determine the exact residual time phosphorous takes to deplete to non-hazardous levels. The index indicated manure spreading should be eliminated when snow is on the ground, so a manure storage pad with three months' capacity was built. Although the implemented program of spreading under weather-appropriate conditions reduced much of the wash-off, the degree of slope still left the field rated "high." The rate of manure application was cut in half, but still the field was high. What finally reduced it to "medium risk" was the introduction of planting corn in contour strips rather than planting the entire field. The farm planners brought overgrown pastures back into production, rotated fields to different crops and expanded the distribution of the manure. Previously, snow and ice from November through April led LaTourette to spread manure excessively on only a few small fields located near the barn and stream. Higher nutrition values in the new crops resulted. They were grown with little or no chemical fertilizer. Thus the pollution hazard, along with fertilizer cost, was cut substantially. Cornell hydrologist Todd Walter says the region's steep slopes, combined with shallow top soil, make for quick saturation of the land. Once soaked, additional rain and snow melt runs off very quickly as the primary source of phosphorous flow. This principle allows phosphorous to collect in lesser amounts on slopes and in greater amounts on flat land because the water carrying it travels in the sub-surface streams and accumulates as it moves downhill. Current thinking is that all the land isn't leaching uniformly. Rather, phosphorous moves to low-level collection points and from there becomes a threat to streams during heavy rain. The Cornell planners have devised a spreadsheet program that combines a soil management routing model (SMRM) with data such as cultural parametres (for example, "Will neighbours mind if I spread manure on this field"); this allows them to rank the fields for phosphorous flow potential. Present research is breaking the acreage down from individual fields to sections of each field. Measurements of nutrient levels show the index and routing model predictions to be in sync with actual phosphorous movement. Research on a nearby farm showed that spreading all manure in October or April, at one end or the other of the cropping sequence, worsened phosphorous runoff. Ultimately, it was found that storing all the winter manure and spreading it in early to mid-autumn reduced new phosphorous loading by about half. Working under the plan for nearly two years, LaTourette and McClennon have modified their operation appropriately and are considering other moves. They now strip crop higher up on the field than LaTourette's former planting, making machinery operation more dangerous. Consequently, they're discussing cutting out corn production altogether in favour of stronger grass management to eliminate the rollover danger. And due to the large volume of water being pumped there, the leach field for the above-ground drain pipe is excessively wet. The land remains saturated nearly all the way back to the stream. They'd like to extend the pipeline another 150 feet to drain farther away from the stream, then fence in the new area to keep the herd off the wet land.
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