Download the Conference Proceedings
Proceedings
Authors
| Filter results9 paper(s) found. |
|---|
1. Phosphorus and Potassium How Low Can You Go In Alfalfa?Tissues testing whole alfalfa plants at harvest can more accurately direct nutrient decisions. Developing critical nutrient levels in-season improves recommendations and applications, saving producers time, expense and effort since many growers take samples for hay quality. These three experiments were designed as follows: 1) Phosphorus (P) Rate study with differing rates of P2O5 using monoammonium phosphate (MAP); including: 0, 30, 60, 120, 240 lb P2O5... S. Norberg, S. Fransen, J. Harrison, D. Llewellyn, L. Whitefield |
2. Regional Water Board Impacts on Vegetable Production in CaliforniaMore than 300,000 ha of vegetable crops are produced annually in the coastal valleys of central California. In these valleys vegetable production dominates the landscape, and since most fields produce two or more crops per year the annual fertilizer input is very high. Not surprisingly, environmentally problematic levels of soluble phosphorus in surface waters, and nitrate-nitrogen (NO3-N) in both surface- and groundwater, are common. The Central Coast Regional Water Quality Control Board (WQCB)... T. Hartz |
3. Efficient N Management for High-yield Vegetable ProductionVegetable production is an N-intensive industry; rates of N fertilization can be very high, particularly where multiple crops per year are produced. In vegetable production areas across the country high nitrate-nitrogen (NO3-N) concentration in surface water and groundwater is focusing regulatory scrutiny on fertilization practices. Furthermore, escalating energy prices mean higher N fertilizer costs, making efficient N management an economic as well as an environmental necessity. The basic principle... T. Hartz |
4. Irrigation and Nitrogen Management Web-based Software for Lettuce ProductionLettuce growers on the central coast of California are under increased regulatory pressure to reduce nitrate loading to ground and surface water supplies. Two tools available to farmers to improve nitrogen use efficiency of lettuce are the quick nitrate soil test (QNST) for monitoring soil mineral nitrogen levels and weather-based irrigation scheduling for estimating water needs of the crop. We developed a web-based software application, called CropManage (https://ucanr.edu/cropmanage), to facilitate... M. Cahn, R. Smith, T. Hartz, B. Noel |
5. Efficient N Fertility and Irrigation Management in Vegetable and Berry ProductionNitrogen (N) fertility and irrigation management for vegetable and berry production has historically been done on an ‘agronomic’ basis, with the sole focus on producing the optimal crop. For these crops N fertilizer and water costs are a small portion of overall production costs, and an even smaller portion of crop value; consequently, these inputs have not been scrutinized as closely as they have been for lower value crops. However, throughout the West concern over environmental water... T. Hartz, R. Smith, M. Cahn |
6. Cropmanage: an Online Decision Support Tool for Irrigation and Nutrient ManagementVegetable and berry growers on the central coast of California are under growing regulatory pressure to reduce nitrate loading to ground and surface water supplies. Two tools available to farmers to improve nitrogen use efficiency of these crops are the soil nitrate quick test (SNQT) for monitoring soil residual N concentrations and evapotranspiration (ET)-based irrigation scheduling for estimating crop water requirements. We developed a web-based software application, called CropManage (https://ucanr.edu/cropmanage),... M. Cahn, T. Hartz, R. Smith, B. Noel, L. Johnson, F. Melton |
7. Developing Practical Phosphorus and Potassium Tissue Test Recommendations and Utilizing Struvite in Modern Alfalfa SystemsTissue testing whole alfalfa plants at harvest provides opportunities to direct nutrient decision making more accurately. Critical levels developed allow in- season recommendations and applications and would save producers time and effort since growers are already taking samples for hay quality. Three experiments were designed including: P Study with differing rates of P2O5 using monoammonium phosphate (MAP); including: 0, 30, 60, 120, 240 lbs./acre on an 8.1 ppm P soil (Olson P method);... S. Norberg, E. Mackey, S. Fransen, J. Harrison, D. Llewellyn, L. Whitefield |
8. Economics of Alfalfa Fertilization Under Inflated Hay and Fertilizer PricesKnowing critical alfalfa nutrient levels in-season improves recommendations and applications, while at the same time saves producers time, expense and effort since many growers take samples for hay quality. Inflation has doubled hay and fertilizer prices which brings into question how current fertility decisions are made. From 2019-2020 detail information on phosphorus and potassium response was conducted. Two experiments were designed as follows: 1) Phosphorus (P) rate study with differing... S. Norberg, D. Llewellyn, J.P. Driver, S. Fransen, J. Harrison |
9. Soil Greenhouse Gas Dynamics in Response to Dairy Manure Compost in an Almond OrchardApplication of dairy manure compost in soils under almond production may confer benefits such as increased carbon sequestration, improved crop nutrient use efficiency, and reduction of greenhouse gas emissions. Elucidating the mechanisms of greenhouse gas emissions and mitigation is a primary concern in the management of agricultural soils and it is directly linked to nutrient management. Presently, agricultural soils account for 11.2% of U.S. greenhouse gas emissions. Of particular concern is... A. Coyotl, J. Murch, S.S. Khalsa, W.R. Horwath |