Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: December 5, 1997
Publication Date: N/A
Interpretive Summary: A stalk puller leaves boll weevil larvae and pupae and unharvested seed cotton on the soil surface where soil temperatures can exceed 53 degrees C in August, depending on soil type and color and prevailing weather conditions. These high temperatures will desiccate and kill developing boll weevil larvae and pupae in the cotton squares and bolls, and greatly reduce the germination of cotton seed. High soil temperatures and lack of adequate soil-seed contact may be responsible for low cotton seed germination or seedling desiccation shortly after seed germination occurs. Plowing the cotton stalk residue places the boll weevil larvae and pupae in a dark, generally moist environment which actually protects them from adverse environmental conditions, predator insects, birds, and all insecticides. Thus, by use of a cotton stalk puller, the boll weevil populations and fall cotton seedling germination and growth can be reduced when compared to conventional moldboard plowing. Control costs for fall germinated cotton seedlings and wind and water erosion of the soil can be reduced by using the cotton stalk puller.
Technical Abstract: Conservation tillage is important in reducing wind and water erosion as well as reducing soil compaction due to tillage operations. Loss of soil moisture, which evaporates with each tillage operation, is reduced with conservation tillage when a crop residue mulch is retained on the soil surface. This study compared the use of a moldboard plow system with either a rotary mower plus a stalk puller or a flail shredder plus a stalk puller for effectiveness in controlling regrowth cotton and in reducing weed (especially volunteer cotton) and boll weevil populations. The use of a cotton stalk puller is a quick and efficient way to destroy cotton stalks and to leave boll weevil pupae or larvae and cotton seed within the top 2 cm of the soil surface where soil temperatures can reach 54 degrees C or more. High soil temperatures combined with dry conditions will desiccate immature boll weevils and reduce the germination and establishment of volunteer cotton. Plowing the cotton stalk residue places the boll weevil larvae and pupae in a dark, generally moist environment which may be conducive for overwintering in south Texas and northeastern Mexico. Using the stalk puller reduced fall seedling cotton populations in two or three years when compared with the moldboard plow system. Stalk puller treatments exposed weevil infested cotton squares and bolls to higher soil temperatures and lower soil moisture than did the moldboard tillage system.