ROCKY FORD, Colo. -- PAM is not a woman or product sprayed on a frying pan. This PAM is a linear-linked polyacrylamide that, in many trials and demonstrations throughout the western U.S., has significantly reduced erosion-up to 99 percent.
But PAM not only reduces erosion, it also increases infiltration as much as 50 percent. AND-PAM helps in high residue furrow irrigation. Because the water has a low sediment content and sediment does not accumulate in the furrows, water flows under the residue. On untreated furrows, the sediment stacks up against the residue which can cause the rows to break over.
"Reduced erosion, increased infiltration, helps with irrigation on land with high crop residues. These three factors alone make PAM a product that every furrow irrigator should use," according to Jim Valliant, regional irrigation specialist with Colorado State University Cooperative Extension. "However, PAM alone or in combination with HYDROGEL, a cross-linked polyacrylamide, has substantially increased yields in corn, onions, tomatoes, and peppers."
Using a combination of PAM and surge irrigation, erosion was reduced an average of 64 percent while using 25 percent less irrigation water and producing equal yields of 179 bushels per acre of grain corn when compared to untreated conventional irrigated corn in 1996-98. In 1997 and 1998, using conventional irrigation at the Arkansas Valley Research Center, the addition of PAM increased yields an average of six (6) bushels per acre.
In trials at the Arkansas Valley Research Center conducted by Mike Bartolo, soil loss was reduced 47 percent when using PAM on 6 of 11 irrigations and still produced similar total market weight on onions of 370 cwt/ac compared to 357 cwt/ac on the untreated check in the 1996 trials. In 1997, soil loss was reduced 22 percent when PAM was applied on only 3 of 10 irrigations and total yield was significantly increased from 377 cwt/ac on the untreated control as compared to 425 cwt/ac on the PAM treated plots.
Fresh picked tomato yields were substantially increased in 1996 from 14.8 tons/ac on the untreated control to 20.8 tons/ac when using a combination of PAM and HYDROGEL, as a seed treat. Soil loss was reduced 39 percent on the PAM/HYDROGEL area as compared to the untreated control. In 1997, HYDROGEL, either as a seed treat or incorporated in the soil, combined with PAM increased the number of emerging plants from 50 to 300 percent when compared to the untreated control while yields, after thinning, were increased as much as 2.4 tons per acre.
In 1996, soil loss from a Jalapeno pepper field was reduced 47 percent when using PAM as compared to the untreated control. Also, fresh picked pepper yields were increased from 4.0 tons per acre on the untreated control to 8.7 tons per acre on the PAM + HYDROGEL area. On a Mira Sol pepper field in 1997, the combination of PAM + HYDROGEL produced 9.5 tons per acre as compared to 6.5 tons per acre on the untreated check.
At a cost of about $5 per pound and using one pound per irrigated acre per application, PAM does not cost, it pays, according to researchers. On corn, with two applications irrigating every other row, the total cost would be $5 per acre. With an average increase of 6 bushels at $2 per bushel, PAM gave a good return on the investment and that is not even considering the benefit of reducing the loss of topsoil. On the onions using 6 applications at $5 per acre, the total cost would be $30 per acre. With just a 1300 pound increase, the increased gross return at $8 per 50 pound bag would be $208 which would more than cover the cost of the PAM, again giving a good return on the investment .
PAM has also been used to reduce seepage in dirt ditches. Work done with ditch models reduced seepage as much as 60 percent by adding PAM and a soil mix. And PAM added to water in a dirt lateral ditch by Jim Valliant, Colorado State University Cooperative Extension on a BOR grant project, substantially reduced water levels in nearby observation wells as compared to the well in the untreated area. Since PAM is a ultra potent flocculent, the sediment content of the ditch water was reduced as much as 67 percent, which partially sealed the ditch. As a result, ditch seepage was reduced from 0.65 to 0.36 gpm/ft of ditch. Four applications of 10 pounds made the total cost to reduce seepage by 45 percent on 450 feet of ditch only $200.
PAM, made from natural gas, is broken down to carbon and hydrogen by sun and salt and ties up with sediment making it environmentally friendly.
Researchers point out that PAM reduces erosion which removes productive top soil that fill rivers and reservoirs, increases infiltration, increases yields, helps when irrigating with high crop residue, reduces seepage from dirt ditches, is very economical and environmentally friendly.
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