Cornell Management Institute

Department of Crop and Soil Sciences Rice Hall • Ithaca, NY 14853 E-mail: [email protected] (607) 255-1187 http://cwmi.css.cornell.edu Home Garden Use of Milorganite®

What is Milorganite? regulations. So, if Milorganite or any product including composted sludge were used on Milorganite is sold as a product a garden, the produce would not be considered manufactured from treated (also organically grown. known as “”) from plants from the Metropolitan Is it a deer repellent? District. It is marketed for turf, ornamentals, An application to USEPA Office of Pesticides is in shrubs, and the home garden. Sewage are process (as of 10/05) to obtain certification for a semi-solid residue of organic matter generated Milorganite as a deer repellent. This process as a byproduct of wastewater treatment. Much of addresses product toxicity, but does not address its the , and organic matter in the effectiveness as a deer repellent. wastewater ends up in the sewage sludge, providing fertilizer value. However many of the contaminants Preliminary research in NewYork found that and pathogens that enter the wastewater treatment broadcasting Milorganite at 5 pounds/100 sq. feet plants from homes, businesses and industry also twice a month reduced deer damage in the summer end up in the sludges. when alternative foods were available, but did not reduce winter or early spring damage. In another How is Milorganite made? study, Milorganite tied in sachets had a slight Following wastewater treatment processes, excess effect in reducing damage to Yew bushes. water is removed by treating it with polymers and Chrysanthemums in Georgia received less deer squeezing it in a filter press. It is then heated, dried damage in a one-month summer study. and made into small granules. This heating kills viral and bacterial pathogens. The product is a Is it safe? heat dried pellet and not compost. Safe is a relative term. People have different views of how much risk is acceptable. Milorganite Is it organic? and some other sludge products meeting certain The use of the term organic is confusing. criteria are approved by the US Environmental Milorganite (and all sewage sludge products) Protection Agency (USEPA) for distribution for contain organic material (materials derived from any use, including home gardens. However, some living things). However, they are not allowed for people remain concerned about the safety and use in certified organic agricultural production environmental impacts of possible contaminants, according to US Department of Agriculture many of which are not tested. In particular, pharmaceuticals and many toxic organic chemicals are present in sludges but are not regulated or FACT SHEET 2006 monitored. Ellen Z. Harrison Director

Cornell Institute Home Garden Use of Milorganite http://cwmi.css.cornell.edu/milorganite.pdf

Can it be used on food crops? toxic organics that do not degrade, the amount available to the plants will be related to the amount Under USEPA rules, Milorganite can be used of material applied to the soil over time and the without restriction. Current rules in New York concentration in the material being applied. The State (part 360.5) are more restrictive. Based on relatively low concentration of contaminants in NYS rules, a waiting period of 38 months should be Milorganite reduces this risk. observed between application of any sludge product, including Milorganite, and planting of food crops. How can risks be minimized? NYS rules require a label for sludge products stating the type of waste material and the Risks can be reduced by minimizing contact of recommended safe uses, restrictions on use and dogs and children with the material both in storage application rates. and after it is applied to soils. Some dogs are attracted to and eat fecal materials, including What are the chemicals of Milorganite. Thus bags should be stored where concern? dogs cannot access them. Metals: Levels of the nine metals regulated by Limiting the amount used, carefully washing USEPA in Milorganite are well below the maximum produce, or avoiding use on vegetables are also levels allowed. Data are available for a few other ways to reduce risks. metals. concentrations are relatively high (4- It is important to wash hands after handling the 6%), a property Milorganite promotes for greening product or working in soils to which it has been lawns. applied. Organic Chemicals: Milorganite is tested for Milorganite or other sludge-based products such some organic chemicals including PCBs and dioxins as composted sewage sludge may be used on (a group of highly toxic organic chemicals), sports fields and parks for fertilizing turf. If you polybrominated diphenyl ethers (PBDEs which are concerned, find out when and where such are a group of chemicals that have properties materials are used and follow good hygiene similar to PCBs), as well as the 114 organic practices (shower and wash clothes after playing, chemicals that fall under the “priority pollutants” keep small children from the area to minimize designation (a group of industrial water pollutants ingestion). identified in the 1970s by USEPA). If prior use of Milorganite or another product is a Concentrations of organic chemicals in Milorganite concern, it could be diluted or covered by adding are lower than in many sludges (probably due to other soil materials. evaporation during the heat treatment step). Other Resources for the Home Gardener: What are the risks? Organic Matter in the Yard: Soil Ingestion: The primary pathway of exposure www.gardening.cornell.edu/factsheets/orgmatter/ is by ingestion (eating). Dogs and people index.html (particularly children) can ingest Milorganite and Health & Safety Guidance for Small Scale the soil to which it has been applied either Composting: purposefully or simply through hand-to-mouth cwmi.css.cornell.edu/smallscaleguidance.pdf contact. Preventing Animal Nuisances in Small Scale Crop Contamination: Some contaminants may Composting: cwmi.css.cornell.edu/nuisance.pdf end up in crops (either taken up into the plants through the roots or as particles on the plant Small Scale or Backyard Composting site: surfaces). For contaminants like metals and some cwmi.css.cornell.edu/smallscalecomposting.htm

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