How fast do European conifers overgrow wounds inflicted by rockfall?

The capacity of trees to recover from mechanical disturbance is of crucial importance for tree survival but has been primarily investigated in saplings using artificially induced wounds. In this study, mature Larix decidua Mill., Picea abies (L.) Karst. and Abies alba Mill. trees growing on alpine slopes that were wounded by naturally occurring rockfall were analyzed to determine their efficiency in overgrowing wounds. In total 43 L. decidua, P. abies and A. alba trees were sampled. First, 106 samples from 27 L. decidua and P. abies trees were analyzed to reconstruct yearly and overall overgrowth rates. Cross sections were taken at the maximum extension of the injury and overgrowth rates were determined on a yearly basis. Results clearly showed that L. decidua overgrew wounds more efficiently than P. abies with an average overgrowth rate of 19° and 11.8° per year, respectively. The higher on the stem the injury was located, the faster the wound was closed. Young and small trees overgrew wounds more efficiently than older or thicker trees. In contrast, no correlation was observed between injury size or increment before/after wounding and wound closure. Second, cross sections from 16 L. decidua, P. abies and A. alba (54 injuries) were used to assess closure rates at different heights around the injury. Overgrowth was generally smallest at the height of the maximum lateral extension of the injury and increased at the upper and lower end of the injury. The efficiency with which L. decidua closes wounds inflicted by rockfall makes this species highly adapted to sites with this type of mechanical disturbance.

The half-life of Be¹⁰ /

Includes bibliographical references.

Nuclear data for low-power research reactors /

The atomic energy authorities of Canada, the United Kingdom, and the United States have agreed to the public release of certain information on low-power research reactors, including those nuclear properties of uranium of importance to the design and operation of such reactors. The following report is the officially released data.

Scientific report : RF Project 464 /

1. The determination and interpretation of electronic collision cross sections -- 2. An electron spectrometer for the study of inelastic collision cross sections -- 3. The inelastic scattering of electrons by helium -- 4. Inelastic collision cross sections of carbon monoxide -- 5. An electron impact study of nitrogen in the kinetic energy range 400 to 600 volts -- 6. Electronic collision cross sections and oscillator strengths for oxygen in the Schumann-Runge region -- 7. Electronic collision cross sections for oxygen at excitation energies above 10 volts -- 8. Electronic collsion cross sections for nitrogen at excitation energies from 10 to 80 electron volts -- 9. Additional collision cross sections for helium, especially in the ionized continuum -- 10. A collision cross section study of CO₂, with a theoretical study of two transitions -- 11. Further developments in the theory and use of the electron spectrometer -- 12. Electronic collision cross sections of water vapor.

Selected reference material, United States atomic energy program.

v. 1. Research reactors.--v. 2. Reactor handbook: physics.--v. 3. Reactor handbook: engineering.--v. 4. Reactor handbook: materials.--v. 5. Neutron cross sections.--v. 6. Chemical processing and equipment.--v. 7. Eight-year isotope summary.--v. 8. Information sources.

Proceedings.

Cover title: Peaceful uses of atomic energy.

Design for garden pool; grounds of Mr. J.A. Allison

Black and red ink on tracing paper. Plan and detailed cross-sections of pool and drainage details with measurements and materials specified. Signed. 72 cm. x 51 cm. Scale: 1/2 " = 1'. [Marion College] [from photographic copy by Lance Burgharrdt]

Grounds of J.B. Berryman Esq. ... Detail plan for swimming pool

Black and red Ink on tracing paper. General plan with elevations, cross-sections. Signed. 73 cm. x 50 cm. Scale: general plan: 1"=20'; details: 1"=1' and 1/4"=1' [from photographic copy by Lance Burgharrdt]

Plan of the children's camp and detail of pool on the grounds of the Chicago Tuberculosis Sanitarium; Chicago, Illinois

Yellow and black ink on linen. Pool, campfires, camp sites, cross-sections of grades. Signed. 103 cm. x 51 cm. Scale: 1"=20' [from photographic copy by Lance Burgharrdt]

Detail plan of the swimming pool. Property of Mr. Spencer Ewing; Bloomington, Illinois

Ink on linen. Plan, cross-sections, details of metal ladder, rail, drains, pool walls. Signed. 99 cm. x 75 cm. Scale varies [from photographic copy by Lance Burgharrdt]

Estate of Mr. Samuel Insull ...Drain and water supply plan for rose garden. Samuel Insull estate. February 1915.

Pencil, red, blue ink on linen; plans and cross-sections; notes; signed. 99 x 74 cm. Scale: 1” = 10 [from photographic copy by Lance Burgharrdt]

A planting plan for a portion of the estate of L. E. Myers. Lake Geneva, Wisconsin.

Ink on linen; location, type, amount of plantings for areas around residence and vegetable garden (central portion of Mye-2); cross-sections through garden; footpaths; planting list with type, size, quantity; signed. 135x69 cm. Scale: 1"=20' [from photographic copy by Lance Burgharrdt]

Plan of athletic field showing grading and planting for the Oak Park and River Forest Township High School. [Oak Park, Illinois?] Revised December 1915

Pencil, red ink on tracing paper; plan and cross-sections; signed. 105x74 cm. Scale 1"=16' [from photographic copy by Lance Burgharrdt]

A topographical survey of the property for a subdivision.

Ink on linen; topo lines, elevations, trees; cross-sections of road drains and [from photographic copy by Lance Burgharrdt]

A detail plan for the pool and garden on the grounds of Dr. Goethe Link.

Yellow, black ink on linen; plan, four cross-sections; unsigned; 102 x 83 cm.; Scales vary [from photographic copy by Lance Burgharrdt]