49 research outputs found

    Notes on Seed Production in the Smooth Perennial Sow Thistle

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    Sonchus arvensis var. glabrescens Wimm. and Graeb. is at present sparsely distributed in Iowa. The patches are often miles apart. In a number of isolated colonies observed in Clay, Palo Alto, Osceola, Dickinson, Story and Hamilton counties seeds are seldom or never found from July to September. Some tests made relative to the fruiting habits of the Smooth Sow Thistle produced the following results. Self or close pollinated flowers from the same head or from heads in the same colony produced no fruits ( seeds ). Flowers cross-pollinated by brushing with flowers from a distant colony produced almost as many seeds as there were flowers in the head. The heads average about 200 flowers each

    The Ecesis of the Gentian in Relation to Environmental Transition

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    The gentian as a factorial element of the vanishing prairie

    Ecological and Floristic Aspects of Clay and Palo Alto Counties

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    A survey of the native flora of Clay and Palo Alto Counties with reference to plants useful to waterfowl includes the plants useful for food, for nesting materials and for cover. The plants are listed systematically as well as referred to associations. The range of distribution for flora of the state has been extended and some plants apparently new to the state have been recorded

    Notes on the Distribution of Midsummer Bee Plants in the Mississippi Zone of Clayton County

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    With intent to determine (1) what plants were available to bees in late summer, (2) how these plants were located with reference to water reservoirs and (3) which of these plants were most valuable to the bee, some observations were made in Clayton County, Iowa, August 20 to September 9, 1919. The vicinity of McGregor, Beulah, Garnavillo, Guttenberg, Clayton. Prairie-du-Chien, and some of the adjacent islands of the Mississippi about McGregor were visited. Since the water supply is related to the topography and the distribution of plants is relative to both these factors, the geology and topography should be kept in mind

    Iowa Field Notes on Reproduction of Canada Thistle (Cirsium arvense)

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    There is a legend that Canada thistle docs not reproduce viable seed in southern Iowa. There exists diversity of recorded statement as to whether the root or the stem is responsible for the vegetative spreading of this plant. The deep-penetrating and horizontally growing root of Canada thistle appears, if judged by structure and behavior, to be organized for extension of its area of occupation, for water and nutrient absorption, as well as for food storage. It bears numerous upward-growing, stem-producing buds whose photosynthetic activity maintain its supply of carbohydrate food. The plant seeds throughout Iowa wherever male and female plants grow sufficiently close to each other

    An Ecological Study of a Prairie Province in Central Iowa

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    This virgin prairie area is mostly of the kame hill, saucer type. One portion of the territory is probably the pre-Wisconsin bed of the Des Moines River whose course was changed by the ice sheet. The region examined in detail is one mile in radius and bordered by a woodland adjacent to Skunk River

    A Progress Report on the Preservation of the Prairie

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    In accord with the specifications of the Prairie Project sponsored by the Iowa Academy of Science, the following recommendations for preservation of prairie have been co-operatively formulated; a number of the most desirable remaining tracts of prairie representative of virgin soils, flora, and fauna have been described and photographed. Not all of the tracts reported in the survey of the state by counties have been yet inspected. RECOMMENDATIONS FOR PRESERVATION OF PRAIRIE: The preceding brief report on Prairie Areas in Iowa, (Hayden, 1941) which should be preserved has shown: 1. That preservation of representative, selected prairie areas is a practical measure essential for the protection and best use of such natural resources as soil, water, vegetation, and wildlife. 2. It designates the location of the principle areas which should be preserved because they illustrate (1) the location of characteristic soil types of prairie origin, as well as (2) the chief types of vegetation and plant communities with their floral constituents and associated wildlife. 3. It specifies the geographic location of the areas which should be preserved and refers them to the topographic and climatic sections of the state which produced them through natural processes

    Life History of Two Plastic Species of Polygonum; Their Economic Role

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    The fruits of Polygonum coccineum Muhl. and P. natans A. Eaton constitute an important source of food for waterfowl. Both species, particularly P. coccineum, commonly invade crops. Both are widely distributed in Iowa, and have been observed in the field in several forms and varieties: P. natans forma genuinum (A. Eaton) Stanford, and forma Hartwrightii (Gray) Stanford; P. Coccineum forma terrestrae (Willd.) Stanford, forma natans (Wiegand) Stanford, and var. pratincola (Greene) Stanford. The several forms of either species may occur on the single rootstock growing in dry ground bordering ponds. Each species has been converted from terrestrial to aquatic form under experimental control. All forms or varieties fruit under conditions of sufficient moisture. Polygonum natans shows less plasticity of root system than does P. coccineum which invades uplands. There the root system penetrates the soil 12 or more feet, but in aquatic stations only 12 to 18 inches

    The Spread of Perennial Sow Thistle in Iowa

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    Sow thistle is not a thistle as the common name implies, but it belongs nevertheless to the Thistle Family, Compositae. The genus Sonchus, according to Hegi (1931), is widely distributed in cultivated parts of the temperate and even the subtropical world, and the four ruderal species, now extending their range in North America, are found in Europe, Asia, parts of Africa, and South America. They include the perennials Sonchus arvensis L. and Sonchus arvensis L. var. glabrescens Guenth., Grab., and Wimm. as well as the annuals Sonchus asper (L.) Hill and Sonchus oleraceus L

    April Showers

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    April showers once brought forth May flowers, but all the King\u27s horses and all the King\u27s men cannot bring forth wild spring flowers again, if the persistent gatherers of wild flowers leave not some little vestige of life whereby the plant may live again. Shall spring flowers live only in verse, or on hats, for the children in the land where the tall corn grows? Shall there be no more woodland nor prairie, only cow pastures and cornfields? Must flowers be sought only in encyclopaedias and in curios, or in flower gardens of wilder collectors
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