Soil profile modification and cotton production

Campbell, R.B. and Busscher, W.J. and Beale, O.W. and Sojka, R.E. (1988) Soil profile modification and cotton production. pp. 505-509. In: Proc. Beltwide Cotton Prod. Res. Conf. USA-LA-New Orleans, 1988/01/03-08.

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Abstract

Hardpan soils of the southeastern Coastal Plains were
mixed to depths up to 0.61 m in an attempt to alleviate
strength problems associated with a subsurface pan. It
was hypothesized that mixing the dense, coarse-textured
E Horizon with the less dense Ap and the relatively
clayey B horizon would increase the water-holding
capacity of the E and decrease its strength. Mixed
soil did have a higher amount of water held than the
unmixed E, increasing it from 5 to 7% at -200 kPa
matric potential. This would reduce its strength by
approximately 0.1 MPa allowing easier root penetration
whether the increased water is available for uptake or
not. Although seed cotton in the deeply-mixed
treatments outyielded the moldboard-plowed treatments
by 233 kg/ha in one year, they were outyielded by 132
kg/ha in another year. The decrease in strength and
the increases of retention as a result of the mixing
were small and infiltration was unchanged.
Furthermore, mixing of field samples was less
homogenous than lab samples. It is doubtful that the
level of improvement of cotton would warrant the effort
involved in the mixing operation.
Treatments at two sites were split into fertility
subplots. The only significant fertility difference
was between rates of N sidedressed when plants were
about 0.40 m tall. The 20 kg/ha rate outyielded the 67
kg/ha rate by up to 300 kg/ha presumably because the
higher rate encouraged vegetative growth and retarded
boll formation which in turn limited lint and seed
production. Interactions between tillage or mixing and
fertility were non-significant. Plants grew better in
the deeper disturbed soils in dryer years. Other crops
may respond more favorably to the mixing.

Item Type:	Conference or Workshop Item (Paper)
NWISRL Publication Number:	0660
Subjects:	Soil > Chemistry Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:57
Last Modified:	05 Jan 2017 19:20
Item ID:	1049
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/1049