Von Liebig noted in his most famous book that agriculture’s principal objective is the production of digestible N (1). This task was particularly challenging in all traditional (pre-industrial) agricultures. They had 3 ways in which to provide N for crops: i) recycling of organic wastes (mainly crop residues and animal and human wastes); ii) crop rotations including N-fixing leguminous species;...

Currently, several state and federal agencies are proposing upper limits on soil test phosphorus (P), above which animal manures cannot be applied, based on the assumption that high P concentrations in runoff are due to high soil test P. Recent studies show that other factors are more indicative of P concentrations in runoff from areas where manure is being applied. The original P index was dev...

Microbiological analyses of fruits and vegetables produced by farms in Minnesota and Wisconsin were conducted to determine the prevalence of Escherichia coli in pre-harvest fruits and vegetables. During the 2003 and 2004 harvest seasons, 14 organic (certified by accredited organic agencies), 30 semi-organic (used organic practices but not certified) and 19 conventional farms were sampled to ana...

In a 3-yr study, corn dried distillers grains plus solubles (DDGS) were evaluated as a substitute for forage and N fertilizer in yearling steers grazing smooth bromegrass. A total of 135 steers (330 +/- 10 kg) were used in a randomized complete block design to measure the effects of DDGS supplementation and N fertilization on animal and pasture performance. Steers were initially stocked at 6.8 ...

We studied selected tissues from ewes and their lambs that were grazing pastures fertilized with either sewage sludge (treated) or inorganic fertilizer (control) and determined concentrations of alkylphenols and phthalates in these tissues. Mean tissue concentrations of alkylphenols were relatively low (< 10-400 microg/kg) in all animals and tissues. Phthalates were detected in tissues of both ...

Two studies were conducted on the use of solid and microbial fertilizers on rice for four cropping seasons (June to October 2010, January to April 2011, June to October 2011 and January to April 2012) at the RM-CARES experimental area, Philippines. One study was conducted in a converted organic area certified organic by the Organic Certification Center of the Philippines (OCCP) and the other on...

Hydroponic rice fodder can be used as an alternative technology to produce forage overcome the feed scarcity in dry season and lack of land for animal feed. This research was aimed determine growth production given with addition different doses organic liquid fertilizer. designed based on a completely randomized design (CRD) 4 treatments. The treatments this were P0 = without adding fertilizer,...

A field-scale experiment with a complete randomized block design was performed to study the degradation of buried oil on a shoreline over a period of almost 1 year. The following four treatments were examined in three replicate blocks: two levels of fertilizer treatment of oil-treated plots, one receiving a weekly application of liquid fertilizer and the other treated with a slow-release fertil...

There have been several recent developments in slow-release fertilizers. These materials supply nutrients continuously over an extended period in contrast to water soluble fertilizers which are immediately available after incorporation in moist soil. Slow-release fertilizers are not subject to rapid leaching loss and do not easily burn plants from over-application. The major need for slow relea...

Mulching and nitrogen are critical drivers of crop production for smallholders of the Loess Plateau in China. The purpose of this study was to investigate the effect of mulching and nitrogen fertilizer on the soil water content, soil nitrate-N content and vertical distribution in maize root-zone. The experiment was conducted over two consecutive years and used randomly assigned field plots with...