Occurence and effect of Chrysomyxa pirolata cone rust on Picea pungens in Utah

In a rare 1969 epidemic, spruce cone rust caused by Chrysomyxa pirolata infected 40 – 100 percent of trees and 20 – 67 percent of cones on riparian Colorado blue spruce on plots located in a 2200 – 2400 m elevational zone in Huntington Canyon of central Utah. Uredinial and telial sporulation on Pyrola spp. began in mid - June, a time closely correlated with opening of pistillate spruce cones. Come phenology and host habitat, as influenced by elevation, are apparently important factors in the restricted niche of the cone rust fungus in Utah. Several preceding consecutive years with extended periods of spring and fall moisture were associated with occurrence of the epidemic, although no cause - and - effect relationship was established. Weather records indicate that these events are infrequent in this climatic zone, and there was no detectable recurrence of cone rust for at least 9 years following 1969. Outwardly normal seeds developed in diseased cones, but seed germinability was reduced by 25 percent. Aecial spore masses between cone scales, cone resinosis, and distortion of cone scales prevented seed dispersal to the extent that the seed crop was effectually destroyed.     

Foliage age as a factor in food utilization by the western spruce budworm, Choristoneura occidentalis

The influence of current year foliage age on food consumption and utilization by the western spruce budworm, Choristoneura occidentalis (Lepidoptera:Tortricidae), was examined. Larvae were fed immature foliage of Douglas-fir ( Pseudotsuga menziesii var. glauca ), Engelmann spruce ( Picea engelmannii ), and corkbark fir ( Abies lasiocarpa var. arizonica ) in June and August of 1981 and Douglas fir in June and July of 1982. All larvae feeding on early season (June) foliage reached maturity. Larvae feeding on middle (July) and late (August) season foliage died before reaching pupation. Relative growth rate and efficiency of conversion of ingested food decreased with foliage age in both the 1981 and 1982 experiments. Relative consumption rate increased with foliage age in the 1981 and decreased in the 1982 experiment.     

Insect damage, cone dimensions, and seed production in crown levels of ponderosa pine

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Insect damage to second-year cones was generally not significantly different between crown levels, but was significantly different among areas and among trees within areas for Conophthorus, Megastigmus, and Cydia. Both cone length and width were not significantly different between lower and middle crown, but cone length was significantly greater in the upper crown. Seeds per cone ranged from 34 to 66, but the percent of sound seed per cone varied significantly according to the amount of insect damage.        

A sagebrush wilt disease of unknown cause

In a rare 1969 epidemic, spruce cone rust caused by Chrysomyxa pirolata infected 40 – 100 percent of trees and 20 – 67 percent of cones on riparian Colorado blue spruce on plots located in a 2200 – 2400 m elevational zone in Huntington Canyon of central Utah. Uredinial and telial sporulation on Pyrola spp. began in mid - June, a time closely correlated with opening of pistillate spruce cones. Come phenology and host habitat, as influenced by elevation, are apparently important factors in the restricted niche of the cone rust fungus in Utah. Several preceding consecutive years with extended periods of spring and fall moisture were associated with occurrence of the epidemic, although no cause - and - effect relationship was established. Weather records indicate that these events are infrequent in this climatic zone, and there was no detectable recurrence of cone rust for at least 9 years following 1969. Outwardly normal seeds developed in diseased cones, but seed germinability was reduced by 25 percent. Aecial spore masses between cone scales, cone resinosis, and distortion of cone scales prevented seed dispersal to the extent that the seed crop was effectually destroyed.     

Ponderosa pine conelet and cone mortality in central Arizona

Ponderosa pine conelets in 10 stands on the Coconino and Kaibab national forests were observed periodically from July 1982 until they matured in September 1983. Abortion, ponderosa pine cone beetles ( Conophthorus ponderosae Hopkins), and ponderosa pine coneworms ( Dioryctria sp., probably Auranticella [Grote]) were the significant mortality factors. Cattle, tip moths, and squirrels rarely destroyed conelets or cones.     

Pollen evidence of historical forest disturbance on the Wasatch Plateau, Utah

Environmental indicators from lake sediments provide excellent opportunities to improve understanding of forest disturbance processes and corresponding changes in forest composition. Our research provides a methodology for assessing recent, historic, and prehistoric disturbances using lacustrine sediment records. We collected sediment cores from Blue Lake, a small subalpine lake on the Wasatch Plateau in central Utah. These cores record environmental changes caused by both spruce beetle ( Dendroctonus rufipennis Kirby) and human (logging and livestock grazing) modification. We observed deteriorated insect remains in the lake sediments. These remains correspond temporally with a historic spruce beetle outbreak, though alkaline conditions in the lake water may have inhibited preservation of bark beetle remains. Pollen data reveal that despite the unprecedented level of mortality among Engelmann spruce ( Picea engelmannii Parry ex Engelm.) resulting from the spruce beetle epidemic, logging activities subsequent to Euro-American settlement appear to be the most severe disturbance to the Blue Lake watershed over the last 750 years.     

Bionomics of the cone spittlebug, Aphrophora canadensis (Homoptera: Cercopidae) on mugo pine in Idaho

The spittlebug, Aphrophora canadensis Walley (Homoptera: Cercopidae), was discovered at Moscow, Idaho, in 1979 infesting Pinus mugo Turra, an exotic ornamental pine. Masses of spittle, densely populated with nymphs, have continued to be abundant since then. The nymphs congregated and fed mainly on cones and did not cause visible reddening of foliage that is typical of other pine-infesting spittlebugs. Immature stages and behavior are described for the first time and are compared to other nearctic pine-infesting species. Beginning in mid-August, eggs were laid under fascicle sheaths at the bases of needles, where they overwintered. Nymphs appeared in late April and began transforming to adults in mid-July. Mating occurred from early August to late September. Adults lingered in diminishing numbers until mid-October.     

Effect of western white pine cone production variability on mountain pine cone beetle population levels

Yearly variation in numbers of cones produced by western white pine was found to affect the population level of the mountain pine cone beetle. In years when cone production is moderate to heavy, beetle populations increase. Increasing beetle populations are ultimately limited by poor cone crops, which increase competition for nutrients and oviposition sites. Variability in western white pine cone production is regarded as the most important factor regulating populations of the mountain pine cone beetle.        

Observations on natural enemies of western spruce budworm ( Choristoneura occidentalis Freeman)(Lepidoptera, Tortricidae) in the Rocky Mountain area

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Three species of predators and parasites were found associated with western spruce budworm ( Choristoneura occidentalis Freeman) (Lepidoptera, Tortricidae) in Larimer Co., Colorado. These were: Ancistrocerus antilope (Panzer) (Hymenoptera, Vespidae), Goniozus gracilicornis (Kieffer) (Hymenoptera, Bethylidae), and Ceromasia auricaudata Townsend (Diptera, Tachinidae). The first two species stored caterpillars in wooden trap nests, while the third was reared from final instar budworms.     

Aquatic Insects in Montezuma Well, Arizona, USA: A Travertine Spring Mound With High Alkalinity and Dissolved Carbon Dioxide

An annotated list of aquatic insects from the high carbonate system of Montezuma Well, Arizona, USA, is presented for collections taken during 1976-1986. Fifty-seven taxa in 16 families are reported, including new distribution records for Arizona ( Anacaena signaticollis , Laccobius ellipticus , and Crenitulus sp. [nr. debilis ]) and the USA ( Enochrus sharpi ). Larval stages for Trichoptera, Lepidoptera, Megaloptera, Neuroptera, Chironomidae, and Anisoptera were absent even though the habitat lacks fish, and water temperature, dissolved oxygen, available food, and substrata appear adequate in Montezuma Well. The potential importance of alkalinity in restricting these insect groups is discussed.     

Noxious arthropods as potential prey of the venomous Javan slow loris (Nycticebus javanicus) in a West Javan volcanic agricultural system

Arthropods play a significant role in ecosystems as prey for animals such as insectivorous primates. The venomous Javan slow loris (Nycticebus javanicus) is a nocturnal primate endemic to the island of Java, Indonesia. It remains unknown if its venom is partially sequestered from noxious arthropod prey. We studied the little-known arthropod community in a rural agriculture system in West Java, Indonesia, in order to investigate the potential prey and source for sequestration of venom. We found specimens of the partially noxious insect orders Lepidoptera, Hemiptera, Coleoptera, Hymenoptera, Orthoptera and of the class Arachnida in slow loris foraging trees in an agricultural area in West Java, Indonesia. To examine the effects of environmental conditions on the abundance of this food source, arthropods were trapped every two weeks for five months, using sweep net transects, Malaise and pitfall traps. Trap type had a significant effect on taxa caught. Wind strength negatively affected the number of Lepidoptera captured in the Malaise trap and humidity had a confounding effect on Orthoptera caught by sweep net. Despite the short-term nature of our study, by using a combination of trapping methods, we identified a relatively high diversity of insects in a human-dominated landscape. Our results can be used as a basis to understand the proximate and ultimate factors shaping the use of venom by the slow loris as a primate.     

Spruce beetle ( Dendroctonus rufipennis ) outbreak in Engelmann spruce ( Picea Engelmannii ) in central Utah, 1986-1998

Extensive Engelmann spruce ( Picea engelmannii Parry ex Engelm.) mortality caused by the spruce beetle ( Dendroctonus rufipennis Kirby) has been occurring at the southern end of the Wasatch Plateau in central Utah. This spruce beetle outbreak is the largest recorded in Utah history. An extensive ground survey was conducted in 1996 on the Manti-LaSal National Forest, Sanpete and Ferron Ranger Districts, to document mortality and impact of a major spruce beetle outbreak on post-outbreak forest composition. In 1998 the same sites were resurveyed. Survey results indicate Engelmann spruce basal area (BA) loss averaged 78% in trees ≥5 inches diameter breast height (DBH) in 1996. Ninety percent of BA ≥5 inches DBH was lost within the same sites by 1998. Tree mortality of spruce ≥5 inches DBH expressed in trees per acre (TPA) averaged 53% in 1996. In 1998 TPA ≥5 inches DBH mortality averaged 73%. Before the outbreak live Engelmann spruce BA ≥5 inches DBH averaged 99 square feet, and TPA ≥5 inches DBH averaged 97. In the sites surveyed in 1996 and resurveyed in 1998, Engelmann spruce BA ≥5 inches DBH averaged 21 and 9 square feet, and TPA ≥5 inches DBH averaged 43 and 25, respectively. Overstory tree species composition changed from stands dominated by spruce to subalpine fir. Stand ratings for potential spruce beetle outbreaks were high to mostly medium hazard pre-outbreak and medium to primarily low hazard by 1998, as a result of reduction in average spruce diameter, total basal area, and overstory spruce.     

Seed and cone insects associated with Pinus monophylla in the Raft River Mountains, Utah

Yearly variation in numbers of cones produced by western white pine was found to affect the population level of the mountain pine cone beetle. In years when cone production is moderate to heavy, beetle populations increase. Increasing beetle populations are ultimately limited by poor cone crops, which increase competition for nutrients and oviposition sites. Variability in western white pine cone production is regarded as the most important factor regulating populations of the mountain pine cone beetle.        

Number and condition of seeds in ponderosa pine cones in central Arizona

Ponderosa pine cones from 10 areas in Arizona were collected prior to natural seed dispersal and dissected to determine the number of sound, hollow, and insect-damaged seeds in each cone. Total and sound seed yields per cone did not vary significantly among areas but did vary significantly among trees within each area. Numbers of hollow and Megastigmus -infested (Hymenoptera: Torymidae) seeds varied significantly among areas and trees within areas. Numbers of sound seed increased significantly with increasing cone length but did not change with increasing numbers of cones per cluster. The percentages of Megastigmus -infested seed did not change significantly with increasing cone length or number of cones per cluster.     

The influence of fallen tree timing on spruce beetle brood production

This study compared brood production of the spruce beetle ( Dendroctonus rufipennis Kirby [Coleoptera: Curculionidae, Scolytinae]) in downed host material felled during summer and spring seasons on the Wasatch Plateau in south central Utah. Thirty-three matched pairs of Engelmann spruce ( Picea engelmannii Parry ex Engelm.) trees were selected for study in spring 1996. One tree of each pair was cut during August 1996 (summer-felled), and the other tree was cut in early April 1997 (spring-felled), so that trees would be colonized by spruce beetles of the same flight period. Brood adults were collected and counted from bark samples, which were removed from the top, bottom, and sides of all sample trees in October 1998. The number of emergent adults produced in June 1999 was determined from exit holes counted in bark samples removed from these same locations. Mixed-model procedures were used to compare differences in the mean number of adults produced in summer-felled versus spring-felled trees in each year. The results indicated that significantly fewer spruce beetles were produced in summer-felled trees than in spring-felled trees. More brood adults were also present in, or emerged from, unexposed bole aspects (bottom, north, and east) of sample trees than exposed aspects (top, south, and west). These findings suggest that disturbances providing spruce beetles with an abundance of fresh host material in the spring result in the greatest potential for spruce beetle production, particularly beneath unexposed bark aspects. Examples of such disturbances include snow avalanches, blowdown, and snow and ice damage.     

Effects of dwarf mistletoe on spruce in the White Mountains, Arizona

Mortality of spruce in mixed conifer stands moderately to heavily infested with western spruce dwarf mistletoe was two to five times greater than in healthy stands in the White Mountains, Arizona. Ten-year volume growth loss for heavily infected spruce trees ranged from 25% to 40%. Estimates of growth loss for spruce on a stand basis ranged from 10% to 20% in heavily infested stands. Because western spruce dwarf mistletoe is prevalent in the White Mountains and causes increased mortality and reduced growth, its control should be included in management of mixed conifer stands there.     

Insect communities and faunas of a Rocky Mountain subalpine sere

Insect faunas and communities are characterized for herbaceous and tree canopy layers in meadow, aspen, and spruce/fir stages of a northern Utah sere. A greater percentage of species were in Thysanoptera in both aspen strata, and a greater percentage of individuals were in Lepidoptera in aspen canopy. Our sites were quite similar to a wide variety of other terrestrial sites in their distribution of species or individuals among orders or metamorphosis categories. Insects/m 2 peaked in the aspen stage, but declined in the herbaceous layer with succession. Insects/plant biomass in the herbaceous layer increased with succession. Insects/m 2 and insects/foliar biomass were higher in aspen canopies than in conifer canopies. Insect species/m 2 peaked in the aspen stage. This statistic was comparable in meadow and aspen understory, and lower in conifer understory. Insects/m 2 in the tree canopies were similar to the values in their respective understories. Insect species/plant biomass increased in the herbaceous layer with succession, but decreased in tree canopies with succession. Species evenness in both strata increased with succession. Adult body length was greatest for meadow species, least for conifer species. Adult body length per individual was greatest in aspen. Life cycle complexity was greatest in aspen. Insects on trees were more likely to have complex life cycles than those on herbs.         

Description,molecular phylogeny,and natural history of a new kleptoparasitic species of gelechiid moth (Lepidoptera) associated with Melastomataceae galls in Brazil

The male, female, pupa and larva of a new species of Gelechiidae (Lepidoptera), Locharcha opportuna Moreira and Becker, are described and illustrated with the aid of optical and scanning electron microscopy. A preliminary analysis of mitochondrial DNA sequences including members of related lineages is also provided. The immature stages are associated with galls induced by a species of Palaeomystella Fletcher (Lepidoptera: Momphidae) on Tibouchina sellowiana (Cham.) Cogn. (Melastomataceae), endemic to the Atlantic Rainforest. Larvae are kleptoparasitic, usurping the gall internal space and thereafter feeding on the internal tissues. By determining the variation in population density of both species and following gall development individually throughout ontogeny under field conditions, we demonstrated that the kleptoparasite completes its life cycle inside galls induced by Palaeomystella, where pupation occurs. The variation in seasonal abundance of the kleptoparasite is tied to that of the cecidogenous species, with their corresponding peaks in density occurring sequentially.

http://zoobank.org/urn:lsid:zoobank.org:pub:525F6D52-8CE1-47D1-A0D9-78B564DF5565     

Infection of young Douglas-firs and spruces by dwarf mistletoes in the Southwest

Mistletoe infection of Douglas-fir and spruce seedlings increased as the mean dwarf mistletoe rating of the overstory, seedling density, and total age of seedlings increased. Percent of spruce seedlings infected increased more rapidly than for Douglas-fir as overstory dwarf mistletoe ratings increased. However, the intensity of infection as measured by the mean dwarf mistletoe rating of seedlings, increased at about the same rate for spruce and Douglas-fir. Percent infection of seedlings less than 20 years total age was higher for spruce than for Douglas-fir. Douglas-fir and spruce seedling mortality was from two to three times greater in heavily infested stands than in healthy stands.