VIEW ARTICLE

A Plant Fumigation Chamber Suitable for Forestry Studies. Charles R. Berry, Principal Plant Pathologist, Southeastern Forest Experiment Station, Forest Service, USDA, Route 3, Box 1250, Asheville, North Carolina 28806. Phytopathology 60:1613-1615. Accepted for publication 5 June 1970. DOI: 10.1094/Phyto-60-1613.

A lean-to greenhouse with a volume of 8.4 m³ is being used to expose potted trees as tall as 2 m to air pollutants. Desired temperature is maintained by an air-conditioner and electric strip heaters. Pneumatic mist nozzles and steam are used to keep relative humidity at specified levels. Sunlight is used for illumination. Phytotoxicants, introduced into the chamber through tubes leading into the air duct system, are monitored with automatic analyzers. Ozone concentrations from 0.0 to 1.0 ppm and sulfur dioxide concentrations from 0.0 to 5.0 ppm can be maintained by manual adjustment of flowmeters or by a recorder-controller. Temperature control can be maintained at ± 1.0 C, and humidity at ± 5%. Humidities near saturation are possible when the air conditioner-compressor is not needed; above 21 C, somewhat lower humidities must be used when cooling is necessary. This chamber differs from similar ones in that it provides, at a relatively small investment, good control of a wide range of temperatures and humidities independent of outside conditions. The chamber is simple to operate and requires little maintenance.