Ground management is a key orchard production practice for profitable and sustainable tree fruit production (Derr, 2001; Geldart, 1994). Effective ground management can control weeds, conserve soil moisture, prevent soil erosion, improve water infiltration and nutrient retention, enhance fruit quality, and maintain or improve soil organic matter and structure (Johnson and Samuelson, 1990; Merwin et al., 1996; Stevenson and Neilsen, 1990). Currently, herbicide application in tree rows with grass alleys between tree rows is the standard orchard ground management practice in the United States (Shribbs and Skroch, 1986). This system aims to provide a vegetation-free zone within the tree rows to minimize weed competition with trees for water and nutrients while maintaining soil structure in the alley (Parker and Hull, 1993). Although in-row herbicide application in orchards is effective in weed control, it is costly and has adversely affected soil ecosystems and the environment. For example, herbicide application in the row area of orchards has reduced soil microbial activities (Elmore et al., 1997; Glover et al., 1999) and elevated herbicide contamination of underground and surface water (Merwin et al., 1996). Therefore, there is a need to replace the traditional in-row ground management method with more sustainable and profitable practices.
Using synthetic fabric, compost, and straw to cover the row area beneath orchard trees is emerging as in-row ground management alternatives to the traditional practice of herbicide applications. Mäge (1982) has demonstrated that polypropylene groundcover could not only control weeds, but also reduce soil water evaporation. Reduced soil water evaporation generally increased soil moisture (Mäge, 1982); under some circumstances, soil aeration may be reduced because of increased soil moisture content and the existence of a physical barrier provided by the polypropylene cover on the soil surface. All these factors could have significant bearings on nutrient availability in soil and nutrient uptake by tree roots. A 6-year study on apple trees in western Canada (Neilsen et al., 2003) reported that the responses of leaf nutrient concentrations to polypropylene groundcover were nutrient-specific and varied with growing season; tree vigor and yield were higher with polypropylene groundcover relative to no cover maintained by herbicide application. Overall, the effects of synthetic polypropylene groundcover on soil nutrient availability, mineral nutrition and productivity of orchard trees, and cash costs and returns are largely unknown in Pacific Northwest tree fruit production systems. The objectives of this study were to (1) examine the effects of synthetic polypropylene groundcover in the tree row area on soil nutrient availability, leaf and fruit nutrition of young sweet cherry, and cash costs and returns; and (2) evaluate the impacts of synthetic polypropylene groundcover in the row area on soil moisture and temperature and the growth, yield, and quality of young sweet cherry. This publication reports the results relevant to the first objective.
Combs, S.M. & Nathan, M.V. 1998 Soil organic matter 53 58 Brown J.R. Recommended chemical soil test procedures for the north central region. NCR Research Publication No. 221 University of Missouri Columbia, Mo
Derr, J.F. 2001 Biological assessment of herbicide use in apple production. II. Estimated impacts following loss of specific herbicides HortTechnology 111 20 25
Elmore, C.L., Merwin, I. & Cudney, D. 1997 Weed management in tree fruit, nuts, citrus and vine crops 17 29 McGiffen M.E. Weed management in horticultural crops ASHS Press Alexandria, Va
Gavlak, R.G., Horneck, D.A. & Miller, R.O. 1994 Plant, soil and water reference methods for the western region W. Reg. Ext. Publ.125. University of Alaska Fairbanks, Alaska
Glover, J.D., Reganold, J.P. & Andrews, P.K. 1999 Systematic method for rating soil quality of conventional, organic, and integrated apple orchards in Washington state Agr. Ecosyst. Environ. 80 29 45
Johnson, D.S. & Samuelson, T.J. 1990 Short-term effects of changes in soil management and nitrogen fertilizer application on ‘Bramley’s Seedling’ apple trees: II. Effects on mineral composition and storage quality of fruit J. Hort. Sci. 65 495 502
Merwin, I.A., Ray, J.A., Steenhuis, T.S. & Boll, J. 1996 Ground cover management systems influence fungicide and nitrate-N concentrations in leachate and runoff from a New York apple orchard J. Amer. Soc. Hort. Sci. 21 249 257
Neilsen, G.H., Hogue, E.J., Forge, T. & Neilsen, D. 2003 Mulches and biosolids affect vigor, yield, and leaf nutrition of fertigated high density apple HortScience 38 41 45
Núñez-Elisea, R., Cahn, H., Caldeira, L. & Seavert, C. 2004 Effect of a synthetic fabric row cover on soil moisture content, growth and fruiting of young sweet cherry trees (Prunus avium L. cv. ‘Regina’/Gisela 6) HortScience 39 850 (abstr.).
Núñez-Elisea, R., Cahn, H., Caldeira, L. & Seavert, C. 2005a Synthetic fabric covers as a tool to promote early yields and fruit quality in ‘Regina’ sweet cherry Compact Fruit Tree 38 38 39
Núñez-Elisea, R., Cahn, H., Caldeira, L. & Seavert, C. 2005b Polypropylene row covers greatly enhance growth and production of fourth-leaf sweet cherry trees HortScience 40 1129 (abstr.).
Shribbs, J.M. & Skroch, W.A. 1986 Influence of 12 ground cover systems on young ‘Smoothee Golden Delicious’ apple trees: I. Growth J. Amer. Soc. Hort. Sci. 111 525 528
Stevenson, D.S. & Neilsen, G.H. 1990 Nitrogen additions and losses to drainage in orchard type irrigated lysimeters Can. J. Soil Sci. 70 11 19
Watson, M.E. & Brown, J.R. 1998 pH and lime requirement 13 16 Brown J.R. Recommended chemical soil test procedures for the north central region. NCR Research Publication No. 221 University of Missouri Columbia, Mo