5 resultados para Vegetative
em Iowa Publications Online (IPO) - State Library, State of Iowa (Iowa), United States
Resumo:
Earthen fills and back slopes resulting from highway building and other construction projects pose problems with respect to erosion stabilization and establishing vegetation cover. Sediments from such slopes create stream pollution while the erosion itself results in maintenance problems. Furthermore, adverse conditions aggravated by erosion prevent satisfactory establishing of vegetative cover. A dense vegetative cover is very effective in controlling erosion but even with optimum weather and soil conditions there is a delay of about 10 weeks between seeding and the establishment of a vegetative cover. Under actual field conditions, 3 months to a year may elapse between completion of construction and establishment of a vegetative cover. A research project was initiated early in 1974 to determine the effectiveness of a rock mulch of crushed limestone aggregates in controlling soil losses on highway construction back slopes in Iowa and to find the influence of such treatments on stand establishment of grasses and legumes.
Resumo:
This publication is designed to help identify the most common trees found in Iowa. It is based on vegetative characteristics including leaves, fruit, and bark. It is neither complete nor without possible oversights. Separate species are grouped by similar characteristics, mainly based on type and arrangement of leaves. These groups are; awl- or scale like needles; single needles, flattened with rounded tips; single needles, square in cross section, with pointed tips; and needles in bundles or fascicles of two or more. Remember, vegetative characteristics are quite variable; use more than one specimen for comparison.
Resumo:
This publication is designed to help identify the most common hardwood or deciduous trees found in Iowa. It is based on vegetative characteristics including leaves, fruit, and bark. It is neither complete nor without possible oversights. Separate species are grouped by similar characteristics, mainly based on type and arrangement of leaves. Remember, vegetative characteristics are quite variable; use more than one specimen for comparison.
Resumo:
Most non-grazed Iowa woodlands and surrounding openings are excellent habitat for a variety of birds and animals if there is a diversity of over story tree species and understory vegetation. As vegetative structures of woodlands change over time, the diversity of the woodland will change, and some species of birds and animals will benefit more then others. To optimize habitat development for the wildest range of bird and animal species, concentrate on maintaining as much vegetative diversity in the woodland as possible. To make improvement for individual species, the special needs of those species will have to be met by targeting precise woodland activities in specific areas.
Resumo:
During 1959, research was continued by the Agronomy Department in cooperation with the Iowa Highway Commission on vegetative establishment and erosion control on highway backslopes (Project 1010). The work was continued at previously established sites and also several new experiments were initiated during the year. The work will be discussed for each separate experiment and location in this report.