Forest Sciences Commons^™

The Effect Of Sodium Chloride On Hybrid Taxodium Selections, Anna Koonce, Edward Bush, David Creech

Faculty Publications

Saltwater intrusion is a major cause of coastal erosion. New hybrid bald cypress species have been shown to exhibit salinity tolerance compared to native bald cypress species. Planting these hybrids, or Nanjing Bot Garden genotype (NBG), trees where their roots can stabilize soil and preserve land may reduce coastal erosion in areas subjected to saltwater intrusion. The purpose of this experiment was to determine whether or not selected bald cypress NBG genotype tree species survive better than native bald cypress trees in areas inundated with saline water. Leaves were harvested, dried and analyzed for their elemental concentration. NBG genotype trees …

Effectiveness Of Plant Species For Removing Atmospheric Ammonia, Marife B. Anunciado, Sheryll B. Jerez, Hans Williams, Joey Bray, Dean W. Coble, Rena Saito

Faculty Publications

Six plant species of Yaupon, Eastern red cedar, American holly, Arizona cypress, Arborvitae and Roughleaf dogwood were utilized to determine their effectiveness in the removal of atmospheric ammonia. All species were exposed to three ammonia levels (1, 5 and 10 ppm) in an environmental chamber. Foliar ammonia content was quantified using an enzymatic technique. The effects of exposure to ammonia on the physiological responses (e.g. photosynthetic activity, stomatal conductance, and transpiration rate) of plants in ambient condition were also determined using an open design photosynthetic gas exchange system. Foliar ammonia content was significantly different among the six plant species (p<0.0001) with Eastern red cedar exhibiting the highest content. The physiological responses differed significantly depending on the plant species and the ammonia treatment level. The photosynthetic response of plants to the presence of ammonia was mixed. At low exposure level, all species except Arborvitae had decreased photosynthetic activity, reducing by as much as 44.5% for Yaupon. At the highest concentration, however, Yaupon’s photosynthetic activity improved by about 10%. Exposure to ammonia caused increased stomatal conductance and transpiration rate on American holly and Arizona cypress, making them more susceptible to water loss.

Stand Risk Rating For The Southern Pine Beetle: Integrating Pest Management With Forest Management, Gordon L. Autry

Faculty Publications

Stand risk rating for the southern pine beetle.

Dendroctonus frontalis Zimm., is a first step toward dealing with a serious but sporadic insect problem. Two approaches, one utilizing readily available resource data, the other employing data obtained from aerial photographs, illustrate application of current knowledge to meet the protection needs of resource management-the primary role of integrated pest management. During a 36-month period in Louisiana, high-risk stands accounted for 13.4 infestations per 1,000 acres, four times the rate of low-risk stands; in Texas high-risk stands accounted for 9 .9 infestations per 1 ,000 acres during 1973-1978, almost five times the …