Forestry, herbicides used

Herbicide use in forestry causes mineralization, thus decreasing the amount of organic compounds in the soil, as well as the overall nitrogen and calcium content. It is an immutable fact that pesticides negatively effect agricultural crops. And this influence is much more serious and varied than pesticide proponents believe. 

Indirect effects can be substantially more far-reaching (in an ecosystem perspective) than direct chemical effects. Most herbicides used in the forest are not likely to directly affect many organisms in any ecosystem because few herbicides used in forestry are so inherently toxic or so widely distributed that the avoidance or detoxification mechanisms of all organisms would be overwhelmed. On the other hand, severe deleterious direct effects on only a few key organisms or ecosystem processes can have far-reaching (indirect) effects for many other components of the ecosystem. 

Biospheric Applications. The current controversies about the dispersal of herbicides used in forestry have demanded the immediate implementation of tracer techniques that can be used in connection vsdth herbicide dispersal. As a result, we have developed a quick and dirty tracer technology. The success of our eflFort has certain consequences concerning strategies for monitoring herbicide dispersal and for establishing legal responsibility for its consequences. 

Lavy, T.L. Mattice, J.D. Project Completion Report to United States Department of Agriculture on Exposure of Forestry Applicators Using Herbicide Formulations Containing 2,4-D,... 

Uses Preemergence or postemergence herbicide used to control many perennial and annual grasses and broad-leaved weeds in ornamental trees and shrubs, forestry, fruits and vegetables. 

T was used for jungle defoliation during the Vietnam war and as an agricultural and forestry herbicide. 

Phenoxyacids (PA) have been widely used as herbicides in agriculture, forestry, and, to a lesser extent, garden activities. The principal products are represented by 2,4-D (2,4-dichlorophenoxyacetic acid) 2,4,5-T (2,4,5-trichlo-rophenoxyacetic acid) and MCPA (4-chloro, 2-methylphenoxyacetic acid) (Stevens and Sumner, 1991). 2,4,5-T has been banned in many countries for a long time because of contamination of the commercial formulations of 2,4,5-T by 2,3,7,8-tetrachlorodibenzodioxin. At present, dioxin contamination of these formulations has been reduced to very low concentrations. 

Insecticides and fungicides used in interiors are the same as those used in agriculture and forestry, but herbicides are seldom applied indoors (Butte, Schencke and Heinzow, 2006). In contrast to the outdoor environment, where modern pesticides are degraded rather quickly by microorganisms, hydrolysis and UV light, biocides applied indoors tend to be persistent. Adsorbed to a dry and dark medium such as house dust, an abiotic degradation may hardly occur and... 

Forestry uses of triazines involve only one or two applications on the same site during a rotation, which may span 30-70 years or more. Under these conditions, accumulation of herbicide residues and potential leaching and runoff hazards are greatly diminished. 

Through the years since 1945, more and more biologically active chemicals have been developed, first for agriculture and subsequently many adopted in forestry. By now, some 25 to 30 different chemicals are used as herbicides in forestry (11). 

Many chemicals are regulated by the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), and their properties are as diverse as the properties of ecosystems. In forestry, however, relatively few herbicides are used very much. In fiscal year 1981, for instance, the USDA Forest Service used more than 25 different herbicides in the National Forests, but 2,4-D and picloram alone and in combination accounted for 70% of the total amount of herbicide applied. Atrazine, glyphosate, dalapon, simazine, fosamine, and hexazinone accounted for an additional 18% (2). 

Uses herbicide for pre-emergence control of annual grasses and some broadleaf weeds in cotton, sweet potatoes, tomatoes, vegetables, capsicums, okra, soybeans, groundnuts, tobacco, pome fruit, stone fruit, citrus fruit, bush fruit, strawberries, forestry nurseries, and ornamental plants, shrubs, and trees. 

Chemical Name 4-(4-chloro-2-methylphenoxy)butanoic acid 4-(4-chloro-2-methylphenoxy)-butyric acid Uses herbicide for post-emergence control of annual and perennial broadleaf weeds in cereals, clovers, sainfoin, groundnuts, peas, etc. and also used to control broadleaf and woody weeds in forestry. 

Chemical Name l-butyl-3-(3,4-dichlorophenyl)-l-methylurea N-butyl-N (3,4-dichloro-phenyl)-iV-methylurea Uses pre-emergence herbicide to control grasses and broadleaf weeds in peas, beans, lucerne, garlic, beets, cereals, strawberries, ornamentals and forestry. 

Uses herbicide, pastures, sugarcane, forestry, tree crops... 

Uses herbicide, cotton, alfafa, peanuts, soyabeans, sugarcane,vine, citrus, forestry... 

Uses herbicide, forestry, grasslands, maize, flowers, sorghum, sugarcane... 

Uses herbicide, maize, barley, wheat, cotton, forestry, potatoes,... 

Uses herbicide, citrus, forestry, vineyards Trade names Caragard (Ciba)... 

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