Projected Red Pine Yields from Aldrin-Treated and Untreated Stands Damaged by White Grubs and Other Agents

(excerpt) Young red pines, Pinus resinosa Ait., during the first few years after planting in the Lake States, are vulnerable to several injurious agents, including white grubs, the larvae of May beetles, Phyllophaga spp. (Kittredge, 1929; Craighead, 1950). The pesticide aldrin3 has frequently been applied at planting time to protect seedlings from white grubs. More than 12,000 acres of national forest land were treated with aldrin from 1960 to 1967 in the Lake States; almost 10,000 of these were on the Hiawatha National Forest (Fowler, 1973)

White Grub Populations, Phyllophaga Spp., in Relation to Damaged Red Pine Seedlings in Michigan and Wisconsin Plantations (Coleoptera: Scarabaeidae)

Excerpt: White grubs (Coleoptera, Scarabaeidae), the larvae of May and related beetles, are destructive pests in some young pine plantations in the Lake States Region. They live in the soil and feed on roots of trees and other vegetation. Larvae chew off the smaller and girdle the ldrger roots of pine seedlings, and consequently reduce growth, weaken, and kill the seedlings. Recommendations against planti.ng or for control measures have been made for grub population densities ranging from 4.4/ft2, 2.0/ft.3, 2.0/ft.\u27, down to 0.5 grubs/ft2 of soil surface (Stone and Schwardt, 1943; Rudolf, 1950; Speers and Schmiege, 1961 ; Shenefelt et al., 1954). A study was carried out to accurately assess or predict grub-caused mortality and damage to seedlings from a given grub population density. This information is necessary for making control recommendations

Estimation of bearing contact angle in-situ by X-ray kinematography

The mounted, preloaded contact angle of the structural bearings in the assembled design mechanical assembly was measured. A modification of the Turns method is presented, based upon the clarity and definition of moving parts achieved with X-ray technique and cinematic display. Contact angle is estimated by counting the number of bearings passing a given point as a function of number of turns of the shaft. Ball and pitch diameter variations are discussed. Ball train and shaft angle uncertainties are also discussed

Parasitic suppressing circuit

A circuit for suppressing parasitic oscillations across an inductor operating in a resonant mode is described. The circuit includes a switch means and resistive means connected serially across the inductor. A unidirectional resistive-capacitive network is also connected across the inductor and to the switch means to automatically render the switch means conducting when inductive current through the inductor ceases to flow

Impact of the Redheaded Pine Sawfly (Hymenoptera: Diprionidae) on Young Red Pine Plantations

The ecology of the redheaded pine sawfly was studied relative to its impact on red pine plantations. An ecological model, which formed the basis for socioeconomic analysis, was constructed. Because the sawfly prefers trees under moisture stress, damage is most severe in stands growing on sand blows, where there is competition for moisture from bracken fern and hardwoods, and where soils are too moist, too shallow, or too compacted. Outbreaks also appear to be related to dry years. The sawfly has a variable impact on multiple-use values. Because it injures the least productive trees in a stand, timber is only indirectly affected. Small openings created by tree mortality after an outbreak may provide edge \u27Wildlife habitat. The sawfly has both negative and positive effects on recreationists, depending upon the type of recreation; it may be a nuisance to campers, but may positively influence hunting. Preventive sawfly management involves proper site selection for red pine

Development of an accurate wide range ultra high vacuum gauge calibration method, 29 June 1966 - 28 February 1968

Calibration method and ultrahigh vacuum components for ionization gage and mass spectromete

Development of an accurate wide range ultra high vacuum gauge calibration method

Accurate wide range ultrahigh vacuum gauge calibration method using pressure attenuation, atomic beam, and cryopumping techniques to evaluate system components and performanc

Projected Red Pine Yields from Aldrin-Treated and Untreated Stands Damaged by White Grub (Coleoptera: Scarabaeidae) and Other Agents at Stand Age Ten Years

White grubs affect pine plantations by killing some trees and by reducing vigor and growth of others. Light to moderate mortality only slightly affects timber yields and financial re- turns if the level of trees remains at the number required for full utilization of the site. Reduced height growth, however, lowers apparent site quality and substantially affects yields and financial returns. The 100 year projections suggest that greater product volumes, financial returns. and higher interest rates on the investment will be gained by grub control before tree growth is reduced

Ramanujan sums as supercharacters

The theory of supercharacters, recently developed by Diaconis-Isaacs and Andre, can be used to derive the fundamental algebraic properties of Ramanujan sums. This machinery frequently yields one-line proofs of difficult identities and provides many novel formulas. In addition to exhibiting a new application of supercharacter theory, this article also serves as a blueprint for future work since some of the abstract results we develop are applicable in much greater generality.Comment: 32 pages. Comments welcom