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The Manuscript Works Of S. Fred Prince (1857-1951), Sarah Burke Cahalan, Jason W. Dean 2018 University of Dayton

The Manuscript Works Of S. Fred Prince (1857-1951), Sarah Burke Cahalan, Jason W. Dean

Marian Library/IMRI Faculty Publications

S. Fred Prince, a botanical illustrator and amateur scientist, is a largely unknown artist whose work on the American landscape demonstrates his eligibility to be considered in the lineage of self-taught illustrator-naturalists such as Mark Catesby and Genevieve Jones. In this article, we present a survey of extant Prince materials identified at time of writing, describing their contents and physical characteristics. Beyond this survey and description, we also provide a biographical sketch and timeline of Prince's life.


The Metabolism Of Some Nitrogen-Fixing Clostridia, W. Hillman Willis 2017 Iowa State College

The Metabolism Of Some Nitrogen-Fixing Clostridia, W. Hillman Willis

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Studies have been conducted upon certain nitrogen-fixing clostridia isolated from Tama silt loam and Grundy silt loam, two acid soils widely distributed in Iowa. Tests have been made of their reaction requirements, capacity to fix gaseous nitrogen and production of carbon dioxide under varying controlled conditions in the laboratory. The results appear to warrant the following conclusions.

1. Nitrogen-fixing anaerobes were present in rather large numbers in the acid soils studied.

2. Varying applications of lime had little or no effect upon the numbers of anaerobic nitrogen-fixers or upon their ability to fix nitrogen in soil-solution cultures in the presence ...


Growth Responses Of The Gladiolus As Influenced By Storage Temperatures, David C. Fairburn 2017 Iowa State College

Growth Responses Of The Gladiolus As Influenced By Storage Temperatures, David C. Fairburn

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The gladiolus, one of the most popular ornamental bulbous plants, is a tender perennial and will not survive if exposed to severe winter weather. The corms must be removed from the garden in the fall and stored until planting time in the spring. The conditions to which the corms are subjected during storage determine to a large extent the growth responses the following season. Consequently, this phase of gladiolus culture is of paramount importance. The present knowledge regarding proper storage temperatures is far from comprehensive. Further study is necessary, and the following investigation concerned with the physiology, morphology and growth ...


Pathogenicity, Host Response And Control Of Cercospora Leaf-Spot Of Sugar Beets, Edgar F. Vestal 2017 Iowa State College

Pathogenicity, Host Response And Control Of Cercospora Leaf-Spot Of Sugar Beets, Edgar F. Vestal

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

On artificial media conidia of Cercospora beticola began to appear in 12 to 20 hours after inoculation, and the optimum production was from 48 to 96 hours after transfer.

Germination of the conidium may take place at any point, but more often near a septum and from the basal end of the cell first.

Germination of the conidia did not take place on the living leaf in an atmosphere containing less than 90 percent humidity.

The humidity of the leaf surface was found to be an average of 3.5 percent higher than the surrounding atmosphere.

An air humidity of ...


Resistance Of Dent Corn To Basisporium Gallarum Moll., C. S. Reddy 2017 Iowa State College

Resistance Of Dent Corn To Basisporium Gallarum Moll., C. S. Reddy

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Injury by Basisporium gallarum is associated with cessation of translocation within the corn plant. It occurs at the time of germination, after normal maturity, and when plants die prematurely from cold or other causes.

Basisporium-infected seed dies within a few days after it is planted in soils slightly below the temperature range for germination. The organism kills the germ before active translocation sets in. Active translocation, in this case, means germination and germination marks a change in the embryo from neutral to acid reaction. Acid reaction in the cob was shown to be correlated with resistance to Basisporium infection. Therefore ...


The Pathogenicity And Seasonal Development Of Gymnosporangium In Iowa, Donald E. Bliss 2017 Iowa State College

The Pathogenicity And Seasonal Development Of Gymnosporangium In Iowa, Donald E. Bliss

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Seven species of the genus Gymnosporangium occur in Iowa, but only G. juniperi-virginianae, causing cedar-apple rust, and G. globosum, causing hawthorn rust, are common. The latter is of little economic importance.

The epidemic of cedar-apple rust in 1928 caused an estimated loss of $200,000 in Iowa.

Six to seven hours were required to produce abundant sporulation from air dry galls of G. juniperi-virginianae regardless of whether the period of soaking was 30 or 180 minutes.

Newly-matured aecidiospores of G. juniperi-virginianae germinated to the extent of 54 percent in July. A lot was divided and the percentage of germination in ...


The Relation Of Moisture To Respiration And Heating In Stored Oats, A. L. Bakke, N. L. Noecker 2017 Iowa State College

The Relation Of Moisture To Respiration And Heating In Stored Oats, A. L. Bakke, N. L. Noecker

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. Considerable variation in oxygen consumption is found even with oats of low moisture content.

2. Heating of oats in well insulated flasks is negligible when the moisture is below 15.00 percent.

3. Oats with the moisture content above 15.00 percent, heated as the moisture content was increased up to 24.00 percent, at which point the maximum heating was reached. When the moisture content was increased beyond 24.00 percent a gradual but irregular falling off in heating was noted.

4. Oats with a moisture content of 40.01 percent consumed the greatest quantity of oxygen, whereas ...


Factors Affecting Experimental Error In Field Plot Tests With Corn, Arthur A. Bryan 2017 Iowa State College

Factors Affecting Experimental Error In Field Plot Tests With Corn, Arthur A. Bryan

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. Data are presented showing the variability among the yields of 2,304 hills of each of three commonly-grown strains of yellow dent corn. The variability among the mean yields of different numbers of randomly drawn perfect-stand hills decreased in close agreement with theoretical expectancy, as the number of hills increased to a total of 192. The reduction was rather small, however, after 48 hills were drawn so that this number may be considered about sufficient to represent a variety.

2. In a comparison of open-pollinated varieties and crosses of inbred lines equal degrees of precision were attained with about ...


Effect Of Time, Depth And Method Of Plowing Upon Yield And Eradication Of Biennial Sweet Clovers, F. S. Wilkins, E. V. Collins 2017 Iowa State College

Effect Of Time, Depth And Method Of Plowing Upon Yield And Eradication Of Biennial Sweet Clovers, F. S. Wilkins, E. V. Collins

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

From the standpoint of amount of dry matter and nitrogen added to the soil and the eradication of the plants, sweet clover may best be plowed for corn about April 25 to May 5. The five dates of harvest used rank as follows in yield of dry matter for tops and roots: May 3-18, Nov. 1-13, Oct. 1, April 9-13 and Sept. 1. Nitrogen yields rank in much the same order.

Of the total for tops and roots, the tops contained 68 percent of the dry matter and 73 percent of the nitrogen in September, 51 and 48 percent, respectively ...


The Production Of Gum By Certain Species Of Rhizobium, Dean A. Anderson 2017 Iowa State College

The Production Of Gum By Certain Species Of Rhizobium, Dean A. Anderson

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

It has long been known that the legume root-nodule bacteria produce a bacterial gum, but knowledge of the exact role of gum production in the metabolism of the organism is still rather incomplete. The results secured by a number of investigators indicate that gum production may be intimately connected in some way with the mechanism of symbiotic nitrogen fixation. In addition, some studies have shown that considerable differences exist in the quantity and chemical nature of the gum produced by different species of Rhizobium.


The Winogradsky Spontaneous Culture Method For Determining Certain Soil Deficiencies, Arthur W. Young 2017 Iowa State College

The Winogradsky Spontaneous Culture Method For Determining Certain Soil Deficiencies, Arthur W. Young

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Various chemical and biological methods have been suggested for the determination of the fertilizer needs of soils but all have been found to be of limited practical value. The search for a suitable method continues, however, and recently Winogradsky3 suggested a biological method which, by more nearly duplicating the conditions existing in the field, would give more accurate results. He devised what has been called the spontaneous culture test. This depends upon the growth of Azotobacter and possibly other aerobic, non-symbiotic, nitrogen-fixing microorganisms on the surface of the soil, treated with a a carbohydrate, calcium carbonate, a phosphate and ...


The Pathogenicity Of Fusarium Niveum (Efs.) And The Development Of Wilt Resistant Strains Of Citrullus Vulgaris (Schrad.), D. R. Porter, I. E. Melhus 2017 Iowa State College

The Pathogenicity Of Fusarium Niveum (Efs.) And The Development Of Wilt Resistant Strains Of Citrullus Vulgaris (Schrad.), D. R. Porter, I. E. Melhus

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Watermelon wilt, caused by Fusarium niveum EFS., is a serious disease in Iowa as well as in many other sections of the United States. The present Iowa acreage is 90 percent less than it was before wilt became a factor.

Infection may occur through the roots formed on a runner covered with infested soil. Injury induced by wind-blown sand seemed to favor wilt infection.

Comparative physiologic tests were made with 18 cultures of Fusarium niveum obtained from widely separated localities. These cultures seemed to differ in: (a) rate of growth on artificial media, (b) type of pigmentation, (c) rate of ...


Some Chemical And Bacteriological Effects Of Various Kinds And Amounts Of Lime On Certain Southern Iowa Soils, R. H. Walker, P. E. Brown, A. W. Young 2017 Iowa State College

Some Chemical And Bacteriological Effects Of Various Kinds And Amounts Of Lime On Certain Southern Iowa Soils, R. H. Walker, P. E. Brown, A. W. Young

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Extensive investigations have been conducted to determine the influence of lime on acid soils, but there is still much to be learned regarding the reactions involved and the effects of additions of various kinds and amounts of lime on different soils. Soils vary widely in physical, chemical and bacteriological properties, and hence lime rarely has the same effect on different types. It has been noted that soils with practically the same hydrogen ion concentration may require different amounts of lime to neutralize the acidity. The organic matter and colloidal content are quite variable and will affect not only the need ...


Methods For Determining Carbon Dioxide Production In Soils, F. B. Smith, P. E. Brown 2017 Iowa State College

Methods For Determining Carbon Dioxide Production In Soils, F. B. Smith, P. E. Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Many investigators have studied the organic matter in soils, in the attempt to determine its nature and composition, the rate and character of the decomposition which it undergoes, the products of decomposition, and especially the value of various kinds of organic materials which may be applied to soils, as indicated by decomposition studies.


The Measurement Of The Degree Of Saturation Of Soils With Bases, R. H. Walker, B. J. Firkins, P. E. Brown 2017 Iowa State College

The Measurement Of The Degree Of Saturation Of Soils With Bases, R. H. Walker, B. J. Firkins, P. E. Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. To determine the degree of saturation of a soil, data must be secured to show the amount of replaceable bases, replaceable hydrogen and base exchange capacity.

2. Experiments have been conducted to determine the accuracy of various methods for these determinations.

3. A study was first made of the electrodialysis method for replaceable bases, using both the Mattson and the Bradfield cells.

4. When 100 grams of soil were electlodialyzed in the Mattson cell for 45 hours, the results seemed satisfactory when compared with the data secured with other methods.

5. When a smaller amount of soil (10 grams ...


A Gene Influencing The Composition Of The Culm In Maize, Merle T. Jenkins, Fisk Gerhardt 2017 Iowa State College

A Gene Influencing The Composition Of The Culm In Maize, Merle T. Jenkins, Fisk Gerhardt

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. A gene influencing the strength of culm in maize has been isolated and found to behave as a simple Mendelian recessive. The character has been called lazy and the factor pail' involved has been degignated La la.

2. Lazy plants are distinguished from their normal sibs by their prostrate habit of growth. Their culms have a much lower breaking strength.

3. The culms of the lazy and normal plants have similar morphological structure, but differ histologically in the thickness of their cell walls.

4. The gene, lazy, exerts a marked influence on the composition of the culm. It greatly ...


Nitrate Assimilation In Soils, F. B. Smith, P. E. Brown 2017 Iowa State College

Nitrate Assimilation In Soils, F. B. Smith, P. E. Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Preliminary work with solution cultures inoculated with soil showed that 20.83 mgm. of nitrate nitrogen disappeared in eight days, while the total nitrogen increased. The results obtained with soil cultures were very similar to those obtained with the solution cultures. Treating the soil with straw in the greenhouse brought about a complete utilization of the nitrates, while there was a small accumulation of nitrate in the soil treated with farm manure.

The nitrate-assimilating power of the soil was influenced by a number of factors, and, altho much information was secured by the methods employed, more work on the various ...


Microbiological Studies Of Some Typical Iowa Soil Profiles, P. E. Brown, T. H. Benton 2017 Iowa State College

Microbiological Studies Of Some Typical Iowa Soil Profiles, P. E. Brown, T. H. Benton

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The determination of the numbers of bacteria, actinomycetes and molds in various horizons of typical profiles of some Iowa soils was made during two seasons and the results compared with careful descriptions of the soil profiles by horizons. The Carrington loam was sampled in typical profiles several times thru the season of 1926 in Buchanan County. The Lindley sandy loam was also sampled at different dates. In 1927 the Carrington loam, the Clyde silty clay loam and the Dickinson fine sandy loam were sampled in the same county at several dates during the early part of the season. In the ...


Acidity Changes Associated With The Keeping Quality Of Apples Under Various Storage Conditions, H. H. Plagge, Fisk Gerhardt 2017 Iowa State College

Acidity Changes Associated With The Keeping Quality Of Apples Under Various Storage Conditions, H. H. Plagge, Fisk Gerhardt

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

This investigation reports a study of. certain acidity changes occuring in Grimes and Jonathan under various storage conditions. Measurements were made of the total titratable acid, the H-ion concentration and, in some instances, the specific gravity of the juice.

Altho total acidity values declined rapidly in the Grimes variety during two weeks of delay at the orchard, its H-ion concentration remained quite uniform. Prolonging the delayed storage period to three weeks, however, resulted in a rather abrupt lowering of the active acidity of the fruit in cold storage. The appearance of soggy breakdown in the stored fruit occurred almost coincidently ...


The Effect Of Delayed Harvest Upon Yield Of Grain, L. C. Burnett, A. L. Bakke 2017 Iowa State College

The Effect Of Delayed Harvest Upon Yield Of Grain, L. C. Burnett, A. L. Bakke

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

In 1927 yield and moisture data were secured at semi-weekly harvest intervals for four varieties of oats, two of winter wheat and two of barley. In 1928 this experiment was repeated using six varieties of oats, two of winter wheat and four of barley.

The data secured in these studies show increases in yields which indicate that photosynthesis and translocation of food material to the kernel may continue much longer than has been previously reported. The yields continued to rise until the moisture content of the grain had fallen to percentages varying, in 1927, between 33.6 and 10.0 ...


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