Forest Fertilization Guidebook Table of Contents]

Environmental protection

Storage and handling of fertilizer

A material safety data sheet for each type of fertilizer should be reviewed by all personnel involved in the fertilization project. These sheets must be kept on site. The data sheet lists preventive and corrective measures for storage and worker safety.


Forest grade urea is not a controlled product under WHMIS (Workplace Hazardous Material Information System) or regulated for rail or road transportation. Because of its solubility in water, however, urea must be stored in dry containers and protected from moisture. Urea is hydrophillic and moisture will make the product go lumpy.

Security of a storage area is important to prevent cattle and wildlife from consuming urea, preventing unauthorized removal of fertilizer, and protecting equipment from vandalism. Since fertilization projects last only 4–5 days at any given site, a night watchman is usually preferable to other methods of security, such as fencing.


Storage areas must be secure to prevent cattle or wildlife from eating fertilizer and to avoid vandalism.

Worker safety

Where prolonged and/or repeated skin and eye contact with urea is likely to occur, workers should wear safety glasses with side shields, shirts with long sleeves, and chemical-resistant gloves. Respirators may be required to prevent overexposure by inhalation where concentrations in air exceed the occupational exposure limits. However this is unlikely unless the fertilizer is being handled in an enclosed space.

Contingency plan

Prior to commencement of projects, a contingency plan must be approved by the district manager and in place, in case of accidental spills of fertilizer.


For areas outside of community watersheds the plan must include:


For areas inside community watersheds the contingency plan must include measures to ensure that water quality is maintained. The contents of the plan must include, but are not limited to, the following guidelines:

The spill contingency plan should be reproduced on waterproof paper and carried in designated vehicles. Ensure the contractor implementing the fertilization application is adequately equipped and trained to take remedial action in case of an accidental spill. If the fertilizer is spilled or applied in non-target areas (e.g., water sources), the contractor shall immediately notify the forest manager. Written notice must promptly follow.

An annual report on all reportable spills and the actions taken will be submitted to the district manager.


Fertilizer applicators must have on site at all times:

Applicators should also have a copy of the silviculture prescription or stand mangement prescription.

Protection of water resource

Nutrients from forest fertilizer applications can enter water bodies through leaching, runoff, or directly when fertilizers are applied aerially. Sensitive areas are protected using buffers and limiting the area receiving the fertilizer treatment. Water quality monitoring (Appendix 4) provides a means of characterizing the background levels of nutrients in sensitive water bodies, and provides a means of confirming the effectiveness of protection measures contained in this guidebook.

Community watersheds

The definition of a community watershed is in the Forest Practices Code of British Columbia Amendment Act, 1995. Community watershed means:
– a waterworks purpose, or
– a domestic purpose if the licence is held by or is subject to the control of a water users’ community incorporated under the Water Act

if the drainage is not more than 500 km2 and the water licence was issued before June 15, 1995.

Additional areas that do not meet this definition may be designated by a regional manager.

Community watersheds include municipal and other water user communities. Water user communities, as defined in the Water Act, have six or more licensed water users (registered with the Water Management Branch) extracting water from the same water source.

Up to 30% of a community watershed can normally be fertilized in any 12-month period. If buffer zones cannot be maintained around at least 75% of the total length of flowing streams then a maximum of 12% of the watershed can be fertilized in a 12-month period.

Do not fertilize in community watersheds if waterbodies contain high chlorophyll levels. Check waterbodies for presence of clumps or strings of periphyton (algae) attached to large stones or aquatic plants. Periphyton strings greater than 3–5 centimetres are indicative of high chlorophyll levels. Such waterbodies may exceed the chlorophyll limits for community watersheds stated in the Silviculture Practices Regulation. Sampling for chlorophyll should not be necessary if care is taken to visually assess the presence of periphyton. Sampling procedures for periphyton are contained in the Biological Sampling Manual, B.C. Ministry of Environment, Lands and Parks, Water Quality Branch. High levels of periphyton can be caused by excess nutrients in the water or the absence of benthic organisms that feed on the algae.

In addition to guidelines established in previous sections, special requirements are needed for fertilizer application in community watersheds. Refer to the Community Watershed Guidebook: Forest Fertilizers.

Fisheries resources

Sensitive aquatic environments that are important for supporting various life history stages of fish must be protected from the direct toxic effects of fertilizer elements (e.g., ammonia, nitrite-N), and indirect effects due to eutrophication. In extreme situations, the eutrophication resulting from excess runoff of fertilizer can lead to a reduction in critical levels of dissolved oxygen necessary to sustain aquatic life, and can cause other habitat impacts. Fisheries-sensitive areas can include fish-bearing streams, tributaries that flow into fish-bearing streams, ephemeral watercourses and flood channels, swamps, seasonally flooded depressions, lake spawning areas, or estuaries.

Protection for these sensitive areas has been provided within this guidebook (see the section on Pre-fertilization block layout) principally through the use of 10-m buffer zones. Fisheries-sensitive areas containing significant numbers of streams that cannot be seen from the air are not appropriate for aerial fertilization. Streams not visible from the air cannot practically be buffered.

Cattle and wildlife

Three aspects should be considered with regard to wildlife when applying fertilizer: the availability, palatability, and inherent toxicity of the applied fertilizer. Urea applied to forest soil as forestry-grade pellets is available to wildlife for a period of a few hours to a few days, depending mainly on precipitation patterns after fertilization. Although small mammals and birds quickly lose interest in the urea pellets, larger wildlife and domestic cattle are attracted to it. Small doses (a few handfuls) of urea are lethal to these animals.

Ruminants such as deer may have a similar reaction as cattle. The prime concern is spills around the loading site.

In range use areas, arrange with the range resource officer to have cattle off the site during treatment. It is improbable that cattle will ingest a lethal dose from a properly spread fertilizer application within the block or from compacted surfaces such as roads or landings. However, cattle are attracted to urea and will even make holes in unopened bags. Therefore, do not leave fertilizer stores unattended on a site if cattle are expected to be in the area.

Daily clean up is required of loading sites to prevent fertilizer being ingested by animals.


Any fertilizer spills must be cleaned up on a daily basis.

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