Tree fruits for Iowa

This bulletin is intended to assist Iowa orchardists in the selection of satisfactory tree fruit varieties either for home or commercial production. By consulting the descriptions and discussions herein given and by informing himself as to the present status of varieties already grown in his locality, the prospective planter should be in a position to make a selection which will succeed and bring him satisfactory returns. Doubtless future years will place different valuations upon many of the varieties discussed for Iowa planting

Varieties of Tree Fruits for Iowa Planting

This circular is intended to assist Iowa orchardists in the selection of satisfactory tree fruit varieties either for home or for commercial production. By consulting the descriptions and discussions herein given and by informing himself as to the present status of varieties already grown in hi.q locality, the prospective planter should be in a position to make a selection which will succeed and bring to him satisfactory returns. Doubtless future years will place different valuations upon many of the varieties discussed for Iowa planting

Apple breeding: A study of Jonathan crosses

Two hundred seventy-three Jonathan seedlings produced by 11 crosses form the basis of the records in this bulletin. These studies show clearly that the progenies produced by the different crosses of Jonathan differ or vary in many important characteristics. These variations are attributed to differences in the genetic constitution of the several varieties which were used in combination with Jonathan, and indicate the relative value of these varieties as parents when crossed with Jonathan. The range of variation in the seedlings of these progenies is generally quite wide both as to tree and fruit. Differences in the horticultural characteristics such as occur in size, form, color, flavor, quality and season of the seedling fruits suggest that multiple factors are concerned, which produce the many variations observed. Jonathan appears to carry as partially dominant factors for medium and below medium size of fruit, but it evidently carries factors also for large and for small size. Factors for roundish, conic, oblate and oblong fruit forms are present. Jonathan appears to be homozygous for red skin color but is heterozygous for pattern and carries factors for both fine and coarse grained flesh, for juiciness, for both acid and sweet flavor and for very good as well as for poor quality. The factors which control the season of the fruit are evidently complex. Jonathan appears to carry factors for season varying from late summer to late winter but probably carries as dominant the factors for mid-winter season. It is of importance to observe that the color, size and flavor of Jonathan were recovered occasionally and that these characteristics were combined with the characteristics of the other parent variety. Colorado Orange produced a higher percentage of fruits of good commercial size than did Salome, Anisim or Roman Stem when crossed with Jonathan. When crossed with Jonathan, Salome produced the highest percentage of fruit rating good and very good, followed in order by Colorado Orange, Anisim and Roman Stem. Late season appeared most often in the seedlings of Colorado Orange and Salome, while Anisim and Roman Stem produced no late season apples. The value of crossing two red apples is shown by the high percentage of good red seedling fruits produced by Anisim and Wealthy when crossed with Jonathan. It is interesting to note that Colorado Orange and Roman Stem produced a high percentage of seedling fruits which were deficient in good red color

Good Lawns are Made

Iowa has the soils and climate for good lawns. To be at their best, lawn grasses need adequate feeding, moderate watering in dry weather and a weed control program. Here are some tips and guides for top-shape lawns

The development of an electrochemical technique for in situ calibrating of combustible gas detectors

A program to determine the feasibility of performing in situ calibration of combustible gas detectors was successfully completed. Several possible techniques for performing the in situ calibration were proposed. The approach that showed the most promise involved the use of a miniature water vapor electrolysis cell for the generation of hydrogen within the flame arrestor of a combustible gas detector to be used for the purpose of calibrating the combustible gas detectors. A preliminary breadboard of the in situ calibration hardware was designed, fabricated and assembled. The breadboard equipment consisted of a commercially available combustible gas detector, modified to incorporate a water vapor electrolysis cell, and the instrumentation required for controlling the water vapor electrolysis and controlling and calibrating the combustible gas detector. The results showed that operation of the water vapor electrolysis at a given current density for a specific time period resulted in the attainment of a hydrogen concentration plateau within the flame arrestor of the combustible gas detector

Determining the alpha dynamo parameter in incompressible homogeneous magnetohydrodynamic turbulence

Alpha, an important parameter in dynamo theory, is proportional to either the kinetic, current, magnetic, or velocity helicity of the fluctuating magnetic field and fluctuating velocity field. The particular helicity to which alpha is proportional depends on the assumptions used in deriving the first order smoothed equations that describe the alpha effect. In two cases, when alpha is proportional to either the magnetic helicity or velocity helicity, alpha is determined experimentally from two point measurements of the fluctuating fields in incompressible, homogeneous turbulence having arbitrary symmetry. For the other two possibilities, alpha is determined if the turbulence is isotropic