Author
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Conn, Jeffery |
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Submitted to: Soil and Tillage Research
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/30/2005 Publication Date: 11/20/2006 Citation: Conn, J.S. 2006. Weed seed bank affected by tillage intensity for barley in Alaska. International Journal of Soil and Tillage Research 90:156-161 Interpretive Summary: Knowing what weed seeds are present in the soil (the weed seedbank) helps to predict the extent of future weed problems. The weed seedbank was found to increase at other locations when tillage is decreased in an effort to reduce soil erosion. A long-term tillage study was started in 1983 to determine what tillage methods would reduce soil erosion under subarctic conditions. The weed seedbank was studied after 10 years of continuous barley crops. The tillage treatments were: no till; disked once; disked twice (once in spring and once in fall); and chisel plow. Soil cores were obtained from each tillage treatment and seeds were manually separated from soil after washing through soil sieves. More seed of shepherds purse (Capsella bursa-pastoris (L.) Medic.), cinquefoil (Potentilla norvegica L.), foxtail barley (Hordeum jubatum L.) and more total seed were found under no-till than under other tillage treatments. More seed were found near the soil surface under no-till and chisel plow treatments than under disked treatments, which helps explain the greater difficulty of controlling weeds that was found in this experiment when tillage was reduced. Technical Abstract: The weed seedbank of a long-term tillage study in subarctic Alaska was studied after 10 years of continuous barley crops. The tillage treatments were: no till; disked once; disked twice (once in spring and once in fall); and chisel plow. Soil cores were obtained from each tillage treatment and seeds were manually separated from soil after washing through soil sieves. Tillage treatment had a significant effect on the number of seeds of shepherds purse (Capsella bursa-pastoris (L.) Medic.), cinquefoil (Potentilla norvegica L.), foxtail barley (Hordeum jubatum L.) and the total number of seed. More seed of these species and more total seed were found under no-till than under other tillage treatments. More seed were found near the soil surface under no-till and chisel plow treatments than under disked treatments, which helps explain the greater difficulty of controlling weeds under reduced tillage. |
