Most of the nation's productive forests are in nonindustrial, private ownership. To meet projected demands, timber harvests will need to increase on these lands. Iowa, which has 0.61 million hectares (ha) or approximately 1.5 million acres of commercial forestland, could benefit from capitalizing on this demand. However, the state's timber resource has been generally under-utilized. For example, Iowans have not harvested poletimber and low-grade sawlog materials from their woodlots because the market for such products has been lacking. Killing such trees to make room for better quality material involves costs that do not immediately increase net returns; thus, incentive to manage these woodlands has not been high.

Those interested in planting black walnuts have lacked information about the best cultivars available for planting in Iowa. This project initiated long-term studies of several varieties of black walnut trees to determine the best cultivars for Iowa growers.

Throughout the Cornbelt eco-region, nitratenitrogen (NO3-N) is the most frequent pollutant exceeding the U.S. Environmental Protection Agency's maximum contaminant limits for municipal drinking water supplies. Agricultural fertilizers that leach or run off from row-cropped fields are the principal source of NO3-N. This potential contamination poses a health concern that is attracting increasing attention among the urban and rural populace alike.

Weed competition and economics are two common barriers to Iowa farmers' investing in tree plantings. This project examined seven weed control strategies and investigated productivity of small grain/forage combinations raised with trees in an effort to suggest management options that would encourage tree planting in the state.

The researchers studied the distribution and abundance of the plant species of farmland woodlots in central Iowa, with particular emphasis on the differences in species composition between sites currently or recently grazed by cattle versus those that had not been grazed for more than 50 years. In addition, various attributes of common species and less common (restricted) species were compared.

The challenges and opportunities, including financial returns, were studied for six different perennial crops that can be used in agroforestry practices. Crops investigated were aronia berry, black walnut, chestnut, Christmas trees, elderberry and hazelnut.

Increased corn production to fuel Iowa's ethanol plants leads to diversion of cattle pasture land to cropland. This project looked at the value of using distillers' grain (an ethanol by-product) as a supplement for beef cattle feeding in a forage system.

Three years of experiments were conducted to help increase profit margins for apple growers, cope with new regulations on pesticide use, and deal with increased pesticide resistance by major apple pests and diseases.

Over three years, small willow cuttings ("posts") cut from local sites were planted into the stream bank on six sites along the Middle Raccoon River. These posts stabilize the bank, reducing erosion and protecting water quality. In addition, unlike most riparian buffer planting techniques, they do not take land out of agricultural row-crop production. They also provide shading and enhance wildlife habitat. Plantings are most successful if cut while dormant, planted on rivers or streams that have less than 50,000 acres drainage, and inspected regularly for insect and beaver damage (so that preventive measures may be taken where indicated). This technique was demonstrated to the public via field days and media coverage, and results of a survey assessing attitudes about adoption of the technique are being analyzed.

Investigation of disturbed and intact woodlands herbaceous understories provided information on species present, biomass production and nutrient capture in preserved and secondary forests.