Ponderosa Pine Trees Research Articles

Estimating western pine beetle-caused tree mortality for evaluating an attractive pheromone treatment

Sequential aerial photography was used to detect ponderosa pine trees killed by successive generations of the western pine beetle (WPB),Dendroctonus brevicomis Lec., over a three-year period during a study to evaluate the effectiveness of attractive pheromones for the suppression and survey of WPB. The total number of WPB-killed trees were estimated for each generation, using probability-proportional-to-size sampling procedures. Infested trees at the beginning of the suppression treatment totaled 283. Attacks by three successive WPB generations in 1970 killed 90,83, and 91 trees, respectively. The first generation in 1971 killed 47 trees and the two subsequent generations combined killed a total of 49 trees. During the suppression treatment, tree mortality was concentrated into the suppression plots in comparison to the check plots and the surrounding area. By 1972, tree mortality distribution returned to its original pattern, but at one-tenth the original level, as shown by maps. Recommendations suggest ways to improve the use of aerial photography for studies of WPB-caused tree mortality and population dynamics.

Interspecific inhibition of the response of the bark beetles,Dendroctonus brevicomis andIps paraconfusus, to their pheromones in the field

Ponderosa pine logs infested withIps paraconfusus males inhibited the attraction ofDendroctonus brevicomis in the field to either attractive logs cut from a ponderosa pine tree under attack byD. brevicomis or to their synthetic pheromones,exo-brevicomin, frontalin, and myrcene. Logs cut from trees under attack byD. brevicomis inhibited the response ofI. paraconfusus to logs infested with maleI. paraconfusus.Exo-brevicomin, frontalin, and myrcene did not inhibit their response but verbenone did. Verbenone was found in maleD. brevicomis dissected from attractive logs under attack during the same time the response ofI. paraconfusus was inhibited by these logs.Trans-verbenol andexo-brevicomin were found in femaleD. brevicomis while verbenone,trans-verbenol, and frontalin were found in maleD. brevicomis in relatively large amounts near the beginning of the aggregation phase of host colonization. All of these compounds had decreased at a similar rate 5 days later. This gradual decrease inexo-brevicomin and frontalin probably caused the observed reduction in attraction. The ecological significance of these compounds in relation to termination of the aggregation phase ofD. brevicomis and reduction of interspecific competition is discussed.

Attraction of rhyacionia neomexicana (dyar) 1/ to synthetic pheromones

Abstract The southwestern pine tip moth, Rhyacionia neomexicana (Dyar), is a destructive pest of young ponderosa pine trees. Male moths are attracted to traps containing virgin females, but chromatographic fractions of female abdominal tips failed to entice males. A variety of synthetic materials were field tested at Chevelon, Arizona over a 6‐year period (1971–1976). (Z)‐7‐Dodecen‐l‐ol acetate, (E)‐7‐dodecen‐1‐ol acetate, and especially (E)‐9‐dodecen‐1‐ol acetate were attractive to the male moth. However, none of the synthetic compounds was as effective as live virgin females.

Air Pollution Damage to the Forests of the Sierra Nevada Mountains of California

Numerous oxidant-injured ponderosa pine and other tree species have been detected in the lower elevation forests of the southern Sierra Nevada mountain range of California in the Sequoia National Forest, Sequoia-Kings Canyon National Parks, and on state and private lands. Affected pines were observed in a broad band following the many ridges that rise above the Central Valley floor to the 1900--2600 m elevation. Slight symptoms of ozone chlorotic mottle on ponderosa pine appeared from about 1000 m altitude, increased in severity as elevation increased and then diminished in severity above 2600 m. An apparent east to west gradient of disease was discovered; severity lessened as distance from the Central Valley increased. Atmospheric monitoring in three forested sites suggests that ozone occurs in doses sufficient to elicit symptoms of this widespread disease.

Non-staining fungi associated with the bark beetle Dendroctonus brevicomis (Coleoptera: Scolytidae) on Pinus ponderosa

Three fungi—Ceratocystis nigrocarpa Davidson, an unidentified hyphomycete, and an unidentified basidiomycete—were isolated from extensive non-stained areas of sapwood of ponderosa pine infested with western pine beetle, Dendroctonus brevicomis Lec., in California. The two unidentified fungi were also present in the thoracic mycangium of the female beetle while C. nigrocarpa was found only externally on the beetle. The mycangium and its contents are illustrated. Ceratocystis minor (Hedgc.) Hunt, which was also found externally on the beetle but not in the mycangium, was isolated only from scattered patches of blue-stained sapwood. It is suggested that non-staining fungi play a role in causing the death of ponderosa pine trees attacked by D. brevicomis.

Effect of air pollution on the volatile oil from leaves of pinus ponderosa

The composition of the essential oil from the leaves of photochemical air pollution injured and healthy Pinus ponderosa trees was determined. Methyl chavicol, a product of the carbohydrate-shikimic acid metabolism, was strikingly lower in the injured trees. However, no significant differences were observed in the monoterpenoids.

Oleoresin variability in pinus ponderosa

Monoterpene composition of xylem oleoresin from 139 Pinus ponderosa trees was determined by GLC, together with related parameters of turpentine content of oleoresin, oleoresin exudation pressure, oleoresin yield, and oleoresin propensity to crystallize. Although noncompositional variables correlated poorly or not at all inter se or with turpentine composition, stronger quantitative relationships were found to exist between individual monoterpenes. The results are discussed from the viewpoint of their relevance to the susceptibility of P. ponderosa to bark beetle attack, as well as from the viewpoint of terpene biosynthesis.

Mortality of Ips lecontei Attracted to Ponderosa Pine Trees Killed with Cacodylic Acid1

The Arizona five-spined engraver, Ips lecontei Swaine, attacked ponderosa pine trees poisoned with a fast-acting silvicide containing cacodylic acid (dimethy]arsenic acid). The density of attack and subsequent mortality of the brood and attacking adults varied considerably with the time of year the trees were poisoned. August-treated trees attracted the greatest density of attacks, and the rate of beetle mortality was higher than in trees poisoned at any other time of the year.

Physiological Ecology of Pinus ponderosa in Southwestern North Dakota

Rates of net photosynthesis and dark respiration were examined for native and transplanted Pinus ponderosa trees in semi- arid southwestern North Dakota. Effects on photosynthesis of soil mois- ture, light, temperature, local weather conditions, and seasons were evaluated. Seasonal photosynthesis was highest on mild autumn (or occasional cool summer) days when soil moisture was not limiting. Pinus ponderosa exhibited marked physiological plasticity with regard to temperature acclimation. Distribution of pine and grassland com- munities within the study area appeared to be regulated by in situ physiographic differences in both texture and depth of soil. The rela- tively high photosynthetic and growth rates and abundant reproduction in evidence suggested that many of the sites within the study area were favorable for growth of Pinus ponderosa.

Roost Tree Characteristics for Merriam's Turkey

Measurements were taken on 158 used and 42 unused ponderosa pine (Pinus ponderosa) trees at 12 roosting sites in central Arizona to determine the preferences of Merriam's wild turkey (Meleagris gallopavo merriami) for certain site and tree characteristics for roosting. The measurements included height, dbh, distance from ground to first branch, and age of the tree together with slope, aspect, and distance from permanent water. All but one of the sites contained a group of trees and 10 were located within Y2 mile of permanent water. The number of trees used for roosting in each site ranged from 1 to 37 and averaged 13. A preference was indicated for easterly exposures and tall, mature, open-branched trees with no branches near the ground.

The effect of applied interception on transpiration rates of potted Ponderosa pine

Water was artificially applied to the foliage of small potted ponderosa pine trees to determine the effect of wetting on transpiration rates. By means of unwetted control trees and a prediction equation, the transpiration of wetted trees could be estimated had they not been wetted. The difference between the estimated and actual transpiration was a measure of the transpiration reduction due to treatment. For thirty‐six 2‐hour periods the average transpiration reduction was 14%, or 9% of the applied water. Thus, about 91% of the applied water was a net loss to soil moisture supplies. The saving as a per cent of applied water varied from 4 to 14 and appeared to be weather related. Minimum values were generally observed on both cool, humid days and dry, hot, windy days. Higher savings were observed with more moderate weather. (Key words: Transpiration; interception; soil moisture)

Ecology of the Vegetation of a Second‐Growth Sequoia Forest

Studies were made of an 80—acre tract of big tree forest which was logged about 1875 for sugar pine, ponderosa pine, and big tree. Disturbances related to logging created conditions ideal for establishment of trees, and a dense second—growth forest has developed. Incense—cedar and white fir are the most abundant trees, but the rapidly growing big trees now dominate in the early successional stages, but now the many species of shrubs and herbaceous plants present occur in low frequency.

DIMENSIONAL AND ZONATIONAL VARIATION IN DORMANT SHOOT APICES OF PINUS PONDEROSA

Tepper, H. B. (State U. Coll. of Forestry, Syracuse, New York.) Dimensional and zonational variation in dormant shoot apices of Pinus ponderosa. Amer. Jour. Bot. 50(6): 589–596. Illus. 1963.—The dimensions and zonation of the apices of the dormant leader and terminal branches in 8 ponderosa pine trees are compared. Apices in upper positions in the crown tend to have larger diameters than those in lower positions. While no consistent trend in the variation of the height of the shoot apex could be demonstrated, the height/diameter (H/D) ratio of the apex increases in progressively lower positions in the crown. Correlation analysis of the pooled data from all trees indicates there is no correlation between height and diameter, but that there is a significant correlation between H/D ratio and diameter of the apex. The H/D ratio of apices of small diameter is larger than that in those of large diameter. While the cytohistological zonation of apices in all positions in the crown is similar, apices of largo diameter have a more extensive distal zone, rib meristem zone and peripheral zone than those of small diameter.

Volume and Diameter Growth of Ponderosa Pine Trees as Influenced by Site Index, Density, Age, and Size

Volume and Diameter Growth of Ponderosa Pine Trees as Influenced by Site Index, Density, Age, and Size

Chemical Control of the Pine Needle Scale, Phenacaspis pinifoliae (Fitch) (Homoptera: Diaspididae), in British Columbia

During the past few years the pine needle scale, Phenacaspis pinifoliae (Fitch), has severely injured ponderosa pine, Engelmann spruce, and other evergreens in the Okanagan Valley of British Columbia. The home owner is most concerned because this insect is capable of ruining the appearance of evergreens on his property. Infestations may be severe on trees growing in submarginal forest areas.Field experiments were conducted in the South Okanagan Valley in 1955 to determine whether lime-sulphur, malathion, or Diazinon (0,0-diethyl-0-[2-isopropyl-4-methyl-pyrimidyl (6)] thiophosphate) would control the scale on ponderosa pine trees.

Atmospheric Pollution in the Ponderosa Pine Blight Area

The ponderosa pine trees in the industrialized area north of Spokane, Washington, have exhibited a characteristic reddening of the needles since 1943, known locally as ponderosa pine blight. The blighted area now embraces approximately 50 square miles, and the trees within a 3-square mile area near the center are dead. As a portion of a comprehensive investigation, the concentrations of gaseous fluorine and sulfur compounds in the air during the growing season of 1950 have been determined through operation of twelve air-sampling stations and a mobile air-analysis laboratory. Analysis of rain-water samples obtained during each rainy period throughout October and November 1950 at 82 locations established the points of origin of the contaminants and the extent of their dispersion. Meteorological and topographical conditions in the ponderosa pine blight area, which control the dispersion of pollutants and explain the damage and pollutant concentration-patterns, are discussed. Concentrations of gaseous fluorine compounds in the atmosphere of the area will serve as a guide in controlled fumigation of ponderosa pine.