Herbicide technology has evolved with forest management in North America over the past 60 years and has become an integral part of modern forestry practice. Forest managers have prescribed herbicides to increase reforestation success and long‐term timber yields. Wildlife managers and others interested in conserving biodiversity, however, have often viewed herbicide use as conflicting with their objectives. Do herbicides increase forest productivity, and are they compatible with the objectives of wildlife management and biodiversity conservation? Results from the longest‐term studies (10–30 years) in North America suggest that the range of wood volume yield gains from effectively managing forest vegetation (primarily using herbicides) is 30–450% in Pacific Northwest forests, 10–150% in the southeastern forests, and 50–450% in northern forests. Most of the 23 studies examined indicated 30–300% increases in wood volume yield for major commercial tree species and that gains were relatively consistent for a wide range of site conditions. Meeting future demands for wildlife habitat and biodiversity conservation will require that society's growing demand for wood be satisfied on a shrinking forestland base. Increased fiber yields from intensively managed plantations, which include the use of herbicides, will be a crucial part of the solution. If herbicides are properly used, current research indicates that the negative effects on wildlife usually are short‐term and that herbicides can be used to meet wildlife habitat objectives.

Residues of glyphosate (N-phosphonomethylglycine) and its metabolite aminomethylphosphonic acid (AMPA) were followed on three forested sites in Oregon, Michigan, and Georgia. Eight-hectare residual stands of low-quality hardwoods were treated with 4.12 kgha glyphosate ae applied aerially in late summer. Residues were highest in upper crown foliage. Overstory reduced exposure of understory vegetation and streams. Residues in streams were close to the detection limit or undetectable in 3-14 days. Residues in soils were highest where cover was sparse and where litter was removed. No residues were detectable in soil 409 days after treatment; movement below 15 cm was negligible. AMPA appeared at low levels in all degrading matrices, including sediments, soon aRer deposition of glyphosate. In pond sediments, both glyphosate and AMPA remained bound and inactive. Residue concentrations in foliage, water, and soil were below levels known to be biologically active in nontarget fauna.

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