Notes on Insects, Especially Gymnaetron spp. (Coleoptera: Curculionidae), Associated with Toadflax, Liniaria vulgaris Mill. (Scrophulariaceae), in North America

1959 ◽  
Vol 91 (2) ◽  
pp. 116-121 ◽  
Author(s):  
J. Morris Smith

Linaria vulgaris Mill., known commonly as toadflax or butter-and-eggs, is worldwide in its distribution but is a serious weed only in the Canadian provinces of Alberta, Saskatchewan, and Manitoba (Zilke and Coupland, 1954), where it is increasing in importance (Beck, 1954; Carder, 1956; Forbes, 1957). Smith (1956) correlated its relative insignificance as a weed in the other provinces and in the northwestern United States with the occurrence of the curculionid beetle Gylmnaetron antirrhini (Payk.). Investigations on this and other insects that feed on toadflax and an evaluation of their possible use as biological control agents are reported in this paper; also included are some observations on the weedand its natural enemies made since 1950 in all provinces west of Quebec and in the northwestern United States.

EDIS ◽  
2017 ◽  
Vol 2017 (6) ◽  
Author(s):  
James P. Cuda ◽  
Patricia Prade ◽  
Carey R. Minteer-Killian

In the late 1970s, Brazilian peppertree, Schinus terebinthifolia Raddi (Sapindales: Anacardiaceae), was targeted for classical biological control in Florida because its invasive properties (see Host Plants) are consistent with escape from natural enemies (Williams 1954), and there are no native Schinus spp. in North America. The lack of native close relatives should minimize the risk of damage to non-target plants from introduced biological control agents (Pemberton 2000). [...]


1974 ◽  
Vol 25 (5) ◽  
pp. 775 ◽  
Author(s):  
AJ Wapshere

The distribution in Australia of a vegetable fault in wool caused by Noogoora burr, Xanthium stumarium, is outlined. The climates of the region in Australia where the burr produces maximum contamination of wool and where it is of the greatest economic importance are compared with the climates of North America (Texas) and the Indian subcontinent (New Delhi) from where the cerambycids, Mecas saturnina and Nupserha vexator, have been introduced respectively as biological control agents for the weed. The comparisons suggest that neither agent is climatically pre-adapted to the region in Australia where Noogoora burr has the greatest economic importance. On the other hand, a pyralid moth, Oeobia vevbascalis, from Pakistan is well adapted to the climates of the regions affected.


2021 ◽  
Vol 14 (1) ◽  
pp. 3-8
Author(s):  
Philip W. Tipping ◽  
Melissa R. Martin ◽  
Jeremiah R. Foley ◽  
Ryan M. Pierce ◽  
Lyn A. Gettys

AbstractThe potential of Melaleuca quinquenervia (Cav.) S.T. Blake to reinvade cleared areas was evaluated over a 13-yr period that included two wildfires and the introduction of biological control agents. The first wildfire occurred in 1998 and was followed by a mean of 591.5 recruited seedlings m−2. Recruits from that fire were cleared 7 yr later in July 2005 for a second experiment to evaluate seedling recruitment into cleared areas. Seed rain, seedling recruitment and mortality, and sapling growth rates were measured in four plots located around individual large reproductive trees. A second natural wildfire in 2007 burned through those plots, leading to increases in seed rain followed by a pulse in recruitment of 21.04 seedlings m−2, 96.5% fewer than after the 1998 fire. Recruits in half of the plots around each tree were then treated with regular applications of an insecticide to restrict herbivory by biological control agents, while herbivory was not restricted in the other half. There was no difference in seedling mortality between treatments 1,083 d post-fire (2007) with 96.6% seedling mortality in the unrestricted herbivory treatment and 89.4% mortality in the restricted herbivory treatment. Recruits subjected to the restricted herbivory treatment grew taller than those in the unrestricted herbivory treatment, 101.3 cm versus 37.4 cm. Many of the recruits were attacked by the biological control agents, which slowed their growth. Although solitary M. quinquenervia trees retain some capacity to reinvade areas under specific circumstances, there was a downward trend in their overall invasiveness at this site, with progressively smaller recruitment cohorts due to biological control agents. Land managers should prioritize removing large reproductive trees over treating recently recruited populations, which can be left for many years for the biological control agents to suppress before any additional treatment would be needed.


1979 ◽  
Vol 9 (4) ◽  
pp. 7-14
Author(s):  
Harry G. Johnson

The concept of “brain drain” is in its origins a nationalistic concept, by which is meant a concept that visualizes economic and cultural welfare in terms of the welfare of the residents of a national state or region, viewed as a totality, and excludes from consideration both the welfare of people born in that region who choose to leave it, and the welfare of the outside world in general. Moreover, though the available statistics are far from adequate on this point, there is generally assumed to be a net flow of trained professional people from the former colonial territories to the ex-imperial European nations, and from Europe and elsewhere to North America and particularly the United States. The concept thus lends itself easily to the expression of anti-colonial sentiments on the one hand, and anti-American sentiments on the other. The expression of such sentiments can be dignified by the presentation of brain drain as a serious economic and cultural problem, by relying on nationalistic sentiments and assumptions and ignoring the principles of economics—especially the principle that in every transaction there is both a demand and a supply—or by elevating certain theoretical economic possibilities into presumed hard facts.


Author(s):  
Bruce A. Stein ◽  
Larry E. Morse

The Carolina hemlock (Tsuga caroliniana) survives in just a few rocky streambeds along the lower slopes of the Blue Ridge Mountains. Other species of hemlock abound across the United States, but none bear a close resemblance to this particular tree. The closest relatives of the Carolina hemlock, in fact, survive in only one other forest on Earth, some 7,000 miles away in Hubei province of eastern China. The forests of eastern Asia and eastern North America are so similar that if you were suddenly transported from one to the other, you would be hard-pressed to tell them apart. In the swift mountain streams rushing past these seemingly displaced hemlocks live a number of small, colorful fish known as darters. Darters are found only in North America and have evolved into a prolific variety of fishes. Up to 175 species inhabit U.S. waters, including the famous snail darter (Percina tanasi), which brought endangered species issues to the fore when it held up construction of the Tellico Dam on the Little Tennessee River. How is it that these two organisms, hemlock and darter, one with its closest relatives on the other side of the globe and the other found nowhere else in the world, came to be living side by side? Just how many plants and animals share the piece of Earth that we know as the United States of America? Why these and not others? These are central questions for understanding the diversity of the nation’s living resources. The United States encompasses an enormous piece of geography. With more than 3.5 million square miles of land and 12,000 miles of coastline, it is the fourth largest country on Earth, surpassed only by Russia, Canada, and China. The nation spans nearly a third of the globe, extending more than 120 degrees of longitude from eastern Maine to the tip of the Aleutian chain, and 50 degrees in latitude from Point Barrow above the Arctic Circle to the southern tip of Hawaii below the tropic of Cancer. This expanse of terrain includes an exceptional variety of topographic features, from Death Valley at 282 feet below sea level to Mt. McKinley at 20,320 feet above sea level.


Weed Science ◽  
1987 ◽  
Vol 35 (2) ◽  
pp. 145-148 ◽  
Author(s):  
Jim M. Story ◽  
Robert M. Nowierski ◽  
Keith W. Boggs

A survey was conducted at 88 sites in Montana in 1984 and 1985 to determine the distribution of Urophora affinis Frauenfeld and U. quadrifasciata (Meigen), two seed head flies released on spotted knapweed (Centaurea maculosa Lam. # CENMA) in North America. U. affinis, released in Montana during 1973 to 1977, was found at 40 of the 88 sites. The fly was concentrated within a short radius (about 5 to 8 km) of release sites, even at sites having well-established populations. U. quadrifasciata, released in British Columbia in 1972, but not in the United States, was found at 84 sites. The data suggest that the fly entered the state in the northwest corner and dispersed in a southeasterly direction. There was a strong positive relationship between mean number of galls per seed head and percent infestation for both fly species.


1999 ◽  
Vol 36 (8) ◽  
pp. 1257-1266 ◽  
Author(s):  
Corwin Sullivan ◽  
Robert R Reisz

Isolated skeletal elements of the amphibian genus Seymouria were recently discovered at the Richards Spur locality near Fort Sill, Oklahoma, a prolific source of Early Permian tetrapod remains. Five of the seven described bones are of juvenile size and include three neural arches, a humerus, and a femur, whereas the other two are partial vertebrae, apparently adult. All seven are morphologically similar to equivalent skeletal elements in Seymouria specimens previously collected in Europe and North America, apart from features reflecting the early developmental stage of the juvenile bones. The femur and humerus are clearly distinct from those of other seymouriamorphs such as Ariekanerpeton and Kotlassia. The rarity of Seymouria at the Richards Spur locality implies that it was not a regular component of the fauna, and it is also associated with the less markedly terrestrial assemblage that consistently occurs at localities in the southwestern United States. However, its skeletal morphology and occurrence at terrestrial localities such as Richards Spur imply a primarily terrestrial, rather than an amphibious, mode of life. Conflicting biostratigraphic correlations imply that the exact age of the Richards Spur deposits is uncertain, and equivalence to the Arroyo Formation of Texas may be erroneous.


2020 ◽  
Vol 49 (4) ◽  
pp. 823-828
Author(s):  
Alex N Neidermeier ◽  
Darrell W Ross ◽  
Nathan P Havill ◽  
Kimberly F Wallin

Abstract Two species of silver fly, Leucopis argenticollis (Zetterstedt) and Leucopis piniperda (Malloch) (Diptera: Chamaemyiidae), from the Pacific Northwest region of North America have been identified as potential biological control agents of hemlock woolly adelgid (Hemiptera: Adelgidae: Adelges tsugae Annand) in eastern North America. The two predators are collectively synchronized with A. tsugae development. To determine whether adult emergence of the two species of silver fly are also synchronized with one another, we collected adult Leucopis which emerged from A. tsugae-infested western hemlock [Pinaceae: Tsuga heterophylla (Raf.) Sarg.] from four sites in the Pacific Northwest over a 29-d period. Specimens were collected twice daily in the laboratory and identified to species using DNA barcoding. The study found that more adult Leucopis were collected in the evening than the morning. Additionally, the daily emergences of adults over the 29-d sampling period exhibited sinusoidal-like fluctuations of peak abundance of each species, lending evidence to a pattern of temporal partitioning. This pattern could have logistical implications for their use as biological control agents in eastern North America, namely the need to release both species for maximum efficacy in decreasing A. tsugae populations.


Sign in / Sign up

Export Citation Format

Share Document