Abstract

Karnosky, D.F. and T.R. Myers. 1982. Specify tolerant trees for air polluted areas. Weeds, Trees & Turf 21(3): 56, 60, 62.

This paper will examine methods of reducing air pollution problems on shade trees. Theoretically, all air pollution problems can be prevented by controlling pollutant sources. Unfortunately, we will be faced with some major pollutant problems on trees for many decades to come. As long as the automobile remains our principal source of transportation, for instance, we will likely continue to be faced with two related problems: ozone generated from photochemical reactions involving automobile exhaust products and salt spray related to the use of deicing salts for maintaining clear winter roads. Because trees vary greatly in their responses to air pollutants, some pollutant problems to shade trees can also be minimized by selecting pollution-tolerant trees for plantings in areas where a known pollutant prevails. This paper examines variation in pollutant responses of trees and discusses how this information can be used.

Benson, D.M., J.T. Walker, and K.R. Barker. 1982. Controlling nematode damage. Am. Nurseryman 155(4): 85-89.

Several genera of plant-parasitic nematodes can cause severe damage on various woody ornamentals. However, it is only in the last 30 years that they have been regarded as serious pests of these plants. These pests damage plants in various ways. For example, some invade susceptible roots and cause large galls to form. These pests are called endoparasites. In contrast, other nematodes feed externally. These pests are called ectoparasites. Typically, nematodes are most damaging to plants in light-textured, sandy soils in the coastal plain regions of the Southeast. Woody ornamentals grown in areas that experience periodic droughts are more likely to suffer nematode damage than are plants grown in areas with adequate moisture. These problems can be minimized by a combination of strict sanitation, careful plant selection and chemical soil treatments.

• © 1982, International Society of Arboriculture. All rights reserved.