Canada thistle regrowth control one year after herbicide application in winter wheat

Non-Peer ReviewedA field study was conducted to evaluate the effectiveness of several herbicides for long-term control of Canada thistle growing in winter wheat. Miscellaneous herbicides were applied at the five leaf stage of winter wheat in the presence of Canada thistle (30 plants per square meter). All herbicides gave effective control of Canada thistle top growth but did not increase yields compared to the weedy check. When Canada thistle control was evaluated one year after herbicide application, three of the nine treatments significantly reduced regrowth: 2,4-D amine at 840 g/ha, clopyralid + MCPA ester at 100 + 400 g/ha, and Clopyralid at 200 g/ha. These treatments reduced Canada thistle numbers by 58, 67, and 83 %, respectively. All herbicide treatments significantly reduced Canada thistle dry matter production one year after application as measured by shoot dry weight per square meter. Clopyralid at 100 g/ha in mixture with either 2,4-D or MCPA ester at 400 g/ha, and 2,4-D amine alone at 840 g/ha reduced dry weight of thistle shoots equally. Clopyralid at 200 g/ha was the most effective treatment tested; Canada thistle shoot dry weight per square meter was reduced by 93 % one year following treatment

Analysis of Inclined Shear Waves in Vertical Bluffs

The effect of inclined shear waves on the seismic response of vertical bluffs is analyzed using the generalized hyperelement. The bluffs are modeled as a stepped halfspace in the frequency domain. It is shown that the response, normalized as a function of slope height (H) divided by wavelength (λ), is amplified for waves travelling into the slope and attenuation for waves travelling away from the slope. This amplification can be as much as twice the amplification for vertically propagating waves. The results of the analysis suggest that wave orientation and inclination in relation to the slope may need to be considered in performing stability analyses

CONSTITUTIONAL LAW--FREEDOM OF SPEECH--PERMISSIBLE EXTENT OF LIMITATION

At the present time this nation is greatly concerned over the state of its political health. Advocates of foreign ideologies are asserting their creeds with ever-increasing vigor. The doctrines they propound are generally conceded to be inconsistent with American ideals, and their activity has induced a feeling of alarm, sometimes attended by hostile reaction. There have been instances where this reaction has taken the form of demands that the proponents of these ideas be silenced. In these circumstances, it becomes important to examine the power of state and federal governments to restrict their activities, particularly with respect to the freedom of speech guaranteed by the Constitution

THE COMPULSORY MANUFACTURING PROVISION-AN ANACHRONISM IN THE COPYRIGHT ACT

The protection afforded foreign authors under the United States Copyright Act at the present time is subject to stringent restrictions. Copyright will not be granted to a person who is neither a citizen nor a resident of the United States unless he complies with a great many formalities, and, in addition, conforms with the compulsory manufacturing requirement. It is the object of this comment to examine the manufacturing provision, section 16 of the Copyright Law, and to show why it should be deleted from the act