soak, a 24-h water soak, or a 48-h water soak. Burs were planted into a soil mix, and placed in a greenhouse to monitor germination for 21 d. Water infiltration tests on seed. Water infiltration tests were conducted to further understand treatment
Katherine Kreuser, William C. Kreuser, Gautam Sarath, and Keenan L. Amundsen
Rachel E. Rudolph, Carl Sams, Robert Steiner, Stephen H. Thomas, Stephanie Walker, and Mark E. Uchanski
, reduce soil erosion, increase water infiltration, decrease nutrient loss by leaching, attract beneficial insects, suppress weeds, and/or suppress soilborne pathogens ( Magdoff and Van Es, 2009 ). In New Mexico, where chile pepper ( Capsicum annuum L
P. C. Thurman and F. A. Pokorny
Soil compaction is considered to be a major factor in the loss of grass in established turf plantings. Associated with the onset of soil compaction is a decrease in soil aeration (1), a reduction in gaseous exchange, and reduced water infiltration rates (2, 6, 7). Attempts to increase turf vigor and putting green resiliency by applying higher rates of fertilizer and by increased irrigation have often accentuated long-standing problems of diseases, poor root development, and low water infiltration rates (3,7). Frequent but light irrigations may also contribute to a buildup of harmful salt concentrations in compacted soils (5, 8).
Rachel E. Rudolph, Lisa W. DeVetter, Inga A. Zasada, and Cedar Hesse
production. These positives include reduced soil erosion in continuously cultivated alleyways, improved water infiltration during the wet winters in the PNW, and weed suppression with minimal herbicide or mechanical weeding inputs. The lack of differences
Jack D. Butler
Of the 5000 grass species identified worldwide, more than 1400 may be found in the United States (17). The potential benefits of interplantings in horticultural crops justifies the effort to identify the most appropriate grasses for this practice. Grass interplantings are used to reduce erosion, increase water infiltration into the soil, improve traffic-carrying ability, improve soil structure, limit weed invasion, moderate soil temperatures, and reduce soil contamination of crops. Disadvantages in using grasses for interplantings include increased competition for water and nutrients, harborage of pests, and expense of establishment and maintenance.
J. F. Parr and G. B. Willson
Proper management of organic wastes such as crop residues, animal manures, and sewage sludges on land is essential for protecting agricultural soils from wind and water erosion, and for preventing nutrient losses through runoff. Efficient and effective use of these materials also provides one of the best means we have for maintaining soil productivity by recycling plant nutrients and by improving soil physical properties. The beneficial effects of organic wastes on soil physical properties are widely known (1, 21) as evidenced by increased water infiltration, water-holding capacity, water content, aeration and permeability, soil aggregation and rooting depth, by decreased soil crusting and runoff, and by lower bulk density.
Hyun-Sug Choi, Curt Rom, and Jason McAfee
Mulch may affect soil chemistry, soil microclimate, biological communities, and tree performance. The trial was conducted to evaluate the effects of different orchard mulches on leaf nutrition, soil moisture, bulk density, root density, and water infiltration for understanding potential use in organic orchards for weed control and as a nutrient resource. Black plastic, hardwood chips, and shredded white paper were applied to three apple cultivars, `Gala', `Jonagold', and `Braeburn' on M.9 rootstocks. A control was sprayed with contact herbicide. Trees grown in hardwood mulch had the highest foliar P and K in year 3. Trees in other mulches showed no difference of leaf nutrition in year 5. All treatments had consistently higher soil moisture than control in year 1, 2, and 4. Mulch did not affect soil bulk density in year 2. The root density was lowest under black plastic mulch in year 2, but was similar in all treatments in year 3. In year 2, water infiltration was fastest in hardwood mulch and control treatments.
I.A. Merwin and W. C. Stiles
Eight groundcover management systems (GMS) have been evaluated since 1986 in an apple orchard replant site. Tree-row GMS have included post-emergence herbicide (glyphosate) “killed sods,” pre-emergence herbicide (norflurazon + diuron) strips, a crownvetch “living mulch,” hay-straw mulch, monthly cultivation, a close-mowed sod, and an unmowed, chemically growth-regulated (maleic hydrazide + 2,4-D) sodgrass. Soil organ&matter content, surface aggregate structure, and water infiltration have improved under vegetative groundcovers relative to herbicide treatments. Extractable soil N, K, P and B have increased under straw mulch. Except for K, foliar nutrient content (dry wt basis) has not been closely coupled with soil nutrient content. Leaf K, P and B contents have increased, while leaf N, Mg and Zn, have decreased in trees in sodgrass relative to herbicide GMS.
Soil water content (SWC) is a soil property that plays a crucial role in a large variety of biophysical processes, such as seed germination, plant growth, and plant nutrition. SWC affects water infiltration, redistribution, percolation, evaporation, and plant transpiration. Indeed, the quantification of SWC is necessary for a variety of important applications in horticultural systems, such as optimization of irrigation volumes, fertilization, and soil-water-budget computations. In recent decades, a substantial number of different experimental methods have been developed to determine the SWC, and a large body of knowledge is now available on theory and applications. In this review, the main techniques used to determine the SWC are discussed, first by describing the physical principles behind the most popular methods and then by addressing how the various spatial scales might affect the different methodologies when applied.
Ray D. William
Extension workers often identify production, marketing, managerial, or educational constraints that reduce agricultural efficiencies. In Oregon, problems expressed by growers of several horticultural crops appeared to have a common soil management component. Some Christmas tree growers, for example, complained about poor vigor and growth of 2nd- or 3rd-cycle trees that were planted immediately after harvest of the previous crop. Growers reasoned that poor growth (and reduced marketability) might be caused by increasing concentrations of herbicide residues that resulted from yearly applications of atrazine or hexazinone, rather than soil erosion and related soil management problems. Grape producers and lily bulb growers were concerned about soil erosion, since crops were planted parallel to the slope. Frequent mechanical harvesting of brambles led to growers’ fears of soil compaction, while fruit growers noted slower rates of water infiltration in orchards where natural vegetation is managed with a flail compared to areas interplanted with a sod.