Botany Commons^™

Cover Of Plants With Extrafloral Nectaries At Four Northern California Sites, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Percent cover of plants with extrafloral nectaries was investigated in three California habitats with the same physiognomy as habitats previously studied in Nebraska (perennial native grassland, riparian forest, deciduous forest). In contrast to Nebraska where cover of plants with extrafloral nectaries reached 14 percent, no plants with extrafloral nectaries were found in any California transect. Chaparral was also studied; no plants with extrafloral nectaries were found.

The Flora And Sandhills Prairie Communities Of Arapaho Prairie, Arthur County, Nebraska, Kathleen H. Keeler, A. T. Harrison, L.S. Vescio

School of Biological Sciences: Faculty Publications

The Arapaho Prairie is a 526-hectare (two-section) tract of upland Sandhills prairie located approximately nine miles southwest of the town of Arthur in Arthur Co., Nebraska (Sec. 31, 32 T18N R39W). The Prairie is at the extreme southwest edge of the 52,000-km² Nebraska Sandhills (see Kaul 1975) and is floristically and ecologically typical of the slightly drier, western part of this vegetation type. Sandhills prairie which stretches across much of north central Nebraska is a unique type of "mixed" grassland (Pool 1914, Rydberg 1931, Tolstead 1942, Weaver 1965) created by impact of the dry, continental climate on the extensive …

The Extrafloral Nectaries Of Ipomoea Leptophylla (Convolvulaceae), Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Ipomoea leptophylla Torr. (Convolvulaceae) is a sprawling dry-site morning glory with two types of extrafloral nectaries: foliar nectaries and nectaries on the outside of the sepals. Both are shown to greatly increase insect visitation to the plant. Ants visiting sepal-surface nectaries significantly decrease flower damage caused by grasshoppers and seed losses caused by bruchids. These results are similar to those for I. carnea and other plants whose extrafloral nectary-ant interactions have been studied, but differ in detail. This is the first demonstration of antiherbivore defense of a prairie plant by nectary visitors.

Inflorescence Architecture And Flower Sex Ratios In Sagittaria Brevirostra (Alismataceae), Robert B. Kaul

School of Biological Sciences: Faculty Publications

Two populations of Sagittaria brevirostra from the same lake were sampled 10 years apart and yielded similar data on inflorescence structure and on numbers and ratios of male and female flowers. Larger inflorescences have relatively more male than female flowers than do smaller inflorescences. Pollination success is unrelated to inflorescence size or sex ratio within an inflorescence.

Morphology And Distribution Of Petiolar Nectaries In Ipomoea (Convolvulaceae), Kathleen H. Keeler, Robert B. Kaul

School of Biological Sciences: Faculty Publications

The distribution of petiolar nectaries in 24 species of Ipomoea was investigated. Petiolar nectaries were found on 12 species (8 new reports, 4 confirmations of previous reports) and quoted from the literature as being found on 3 other species; they were absent from 9 species investigated. The structure of petiolar nectaries in the genus ranges from simple beds of superficial nectar-secreting trichomes (1 species), to slightly recessed "basin nectaries" (8 species), to "crypt nectaries," which are structurally the most complex extrafloral nectaries known (3 species). (Structures were not determined for 3 species.) Petiolar nectaries are present in all subgenera, but …

Distribution Of Plants With Extrafloral Nectaries And Ants At Two Elevations In Jamaica, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Frequencies of plants with extrafloral nectaries were determined for two elevations in Jamaica. Extrafloral nectaries were found on 0.28 of the plants at sea level (Happy Grove, Portland) and 0.00 of the plants at 1310 m (Whitfield Hall, St. Thomas). Ant abundance, as indicated by discovery of and recruitment to baits, was greater at the lower elevation site. However, despite the apparent absence of plants with extrafloral nectaries, there were abundant ants at 1310 m.

Species With Extrafloral Nectaries In A Temperate Flora (Nebraska), Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Extrafloral nectaries (EFNs) are glands on a plant, not involved in pollination, that produce solutions containing sugars (and other compounds). Long noted by morphologists, EFNs have recently been observed to be part of ant-plant mutualisms. The function of EFNs appears to be to attract aggressive insects, especially ants, which by disturbing or preying upon herbivores, reduce damage to the plant (Janzen, 1966a,b; Elias and Gelband, 1975; Keeler, 1975, 1977; Bentley, 1976, 1977a,b; Schemske, 1978; Tilman, 1978; Inouye and Taylor, 1979; Pickett ad Clark, 1979). Furthermore, they constitute an unusual plant defense against herbivores: at EFNs plants employ ants as a …

Nocturnal Pollination Of Abronia Fragrans (Nyctaginaceae), Kathleen H. Keeler, Myra S. Fredricks

School of Biological Sciences: Faculty Publications

Abronia fragrans Nutt. (Nyctaginaceae) is a white-flowered herb of dry sandy soils from Idaho and South Dakota to Arizona and Texas. It can be readily observed to fit a night-blooming, moth-pollinated syndrome (Faegri and van der Pijl, The principle of pollination ecology, 1971). This does not seem to have been noted: in all references to A. fragrans we could find, the only indication of nocturnal anthesis was the comment of Nelson (Handbook of Rocky Mountain plants, 1969), who observed that the fragrance was more noticeable at night. Tillett (Brittonia 19:299-327, 1967), working on Pacific species, suggested that the …

The Extrafloral Nectaries Of Ipomoea Carnea (Convolvulaceae), Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

lpomoea carnea (Convolvulaceae) possesses two types of extrafloral nectaries, located on the petiole and on the pedicel. These secrete a complex nectar containing sugars and amino acids. The insects attracted to the extrafloral nectaries are predominantly ants and they are relatively abundant throughout the year. A number of incidents of plant defense as a result of the presence of extrafloral nectary visitors at the extrafloral nectaries of I. carnea were observed and are consistent with the ant-guard theory of the function of extrafloral nectaries.

A Bibliography Of Taxonomic Literature Of The Great Plains Flora, With Supplements I, Ii, And Iii, Ralph E. Brooks

School of Biological Sciences: Faculty Publications

There is at present no recent comprehensive manual of the Great Plains flora. Consequently, students of the flora must utilize monographs, revisions, and other sources in their work. This bibliography was compiled in order to facilitate location of available literature, and will be useful to anyone interested in the systematics of the plants of the Great Plains. This compilation was produced for the Great Plains Flora Association as an initial step in the preparation of a major flora for the region.

References to the plants of the Great Plains region as recognized in the Atlas of the Great Plains Flora …

Mosses Of The Great Plains: Introduction And Catalogue, Steven P. Churchill

School of Biological Sciences: Faculty Publications

This account initiates a series of articles concerning the mosses of the Great Plains. The boundary of this region (Fig. 1) is adopted in part from a parallel study currently in progress on vascular plants (McGregor et aI., 1977). However, in addition, this moss study includes that region of Canada studied by Bird (1962). The total area included in this study of the Great Plains thus occupies about 665 thousand square miles, extending from southern Manitoba to southeastern Alberta, south to northeastern New Mexico and northwestern Oklahoma.

Crum, Steere and Anderson (1973) have listed 1,170 species, 267 genera, and 58 …

Anatomical Observations On Floating Leaves, Robert B. Kaul

School of Biological Sciences: Faculty Publications

An examination of 24 genera of aquatic plants having floating leaves and leaf-like thalli has been made. Functional stomata occur on the adaxial sides of floating leaves of angiosperms and some ferns, and in some floating leaves there are stomata on the abaxial surface as well. Most floating leaves have prominently chambered mesophyll, and in some instances the chambers are locally enlarged and form buoys.

Ipomoea Carnea Jacq. (Convolvulaceae) In Costa Rica, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

This is the first report of Ipomoea carnea (Convolvulaceae) from lowland Costa Rica. These populations are unusual for the species in flower color, flowering season and pollinator. Other aspects of the biology of the species in Guanacaste, especially pollination, flower robbing and extrafloral nectary visitors, are discussed.

Review Of Die Infloreszenzen: Typologie Und Stellung Im Aufbau Des Vegetationskorpers. Zweiter Band. 1 Teil, By Wilhelm Troll. Gustav Fischer, Jena, 1969, Robert B. Kaul

School of Biological Sciences: Faculty Publications

Review of Die Infloreszenzen: Typologie und Stellung im Aufbau des Vegetationskorpers. Zweiter Band. 1 Teil, by Wilhelm Troll. Gustav Fischer, Jena, 1969.

Morphology And Development Of The Flowers Of Boottia Cordata, Ottelia Alismoides, And Their Synthetic Hybrid (Hydrocharitaceae), Robert B. Kaul

School of Biological Sciences: Faculty Publications

The inferior ovary of Boottia cordata, Ottelia alismoides, and their hybrid is appendicular in nature, the carpels are congenitally only slightly connate, and they are unsealed. All floral organs except the sepals originate from common primordia in the female and bisexual flowers. A flat residual floral apex is present. There is a vestigial superior ovary of three ontogeneticallv fused carpels in the male flower of Boottia cordata. The hybrid is intermediate in many characteristics and has partially fertile stamens and staminodia. The sequence of development in all flowers is acropetal. These plants appear to be related to …

Floral Morphology And Phylogeny In The Hydrocharitaceae, Robert B. Kaul

School of Biological Sciences: Faculty Publications

The vascular anatomy of 13 of the 15 genera of the Hydrocharitaceae has been studied, and certain aspects of floral morphology are considered. The flowers of the family show a broad range of specialized structures combined with primitive characteristics. The origin of paired and single stamens is interpreted as probable modifications of fascicled stamens. Extreme reduction in the androecium is shown for several genera. Tendencies toward reduction and fusion within the gynoecium are pronounced. Most genera are at least slightly syncarpous, but a few are apocarpous. The inferior ovary is appendicular in nature, with some genera exhibiting more complete fusion …

Floral Development And Vasculature In Hydrocleis Nymphoides (Butomaceae), Robert B. Kaul

School of Biological Sciences: Faculty Publications

The flower of Hydrocleis nymphoides consists of three sepals which arise in spiral succession, three simultaneously arising petals, numerous stamens and staminodia which arise in centrifugal order, and six carpels. A residual apex remains at maturity. The first-formed members of the androecium are stamens and the later-formed members are staminodia which develop below the stamens and which become outwardly displaced during expansion of the receptacle. The androecium is supplied by branching vascular trunk bundles. The carpels are completely open but the ventral margins are slightly conduplicately appressed basally. A single dorsal bundle provides the stigmatic area with vascular tissue, and …

Development And Vasculature Of The Flowers Of Lophotocarpus Calycinus And Sagittaria Latifolia (Alismaceae), Robert B. Kaul

School of Biological Sciences: Faculty Publications

The development of the bisexual flower of Lophotocarpus calycinus and of the unisexual flowers of Sagittaria latifolia has been observed. In all cases floral organs arise in acropetal succession. In L. calycinus, after initiation of the perianth, the first whorl of stamens to form consists of six stamens and is ordinarily followed by two alternating whorls of six stamens each. The very numerous carpels are initiated spirally. In the male flower of S. latifolia the androecium develops in spiral order. A few rudimentary carpels appear near the floral apex after initiation of the stamens. There are no staminodia. The female …

Ontogeny And Anatomy Of The Flower Of Limnocharis Flava (Butomaceae), Robert B. Kaul

School of Biological Sciences: Faculty Publications

The flowers of Limnocharis flava (L.) Buch. are borne in an indeterminate umbel and each consists of three sepals, three yellow petals, and about 18 carpels surrounded by numerous stamens and staminodia. The androecium is centrifugally developed, and the last-formed members are staminodial; it is supplied by branching vascular systems. Carpels arise almost simultaneously, and a prominent residual floral apex remains. The carpels are partially conduplicately closed and are also primitive in possessing laminar placentation and in lacking differentiation of a style. The gynoecium is essentially apocarpous, but there are slight fusions of adjacent carpels near their ventral margins where …

Rocky Mountain Flowers, Frederic E. Clements, Edith Schwartz Clements

School of Biological Sciences: Faculty Publications

AN ILLUSTRATED GUIDE FOR PLANT-LOVERS AND PLANT-USERS WITH TWENTY-FIVE PLATES IN COLOR AND TWENTY-TWO PLATES IN BLACK AND WHITE

The present book is an endeavor to present the materials of the Rocky Mountain flora in preliminary form from the standpoint of the experimental ecologist. The latter is concerned primarily with the relationships of "species" and their subdivisions as an organic expression or measure of habitat differences, and of the competitive relations of the various formations. Whatever the taxonomic value of the numerous segregates of the last decade or two, the fact that the binomial form conceals the relationship to the …

The Relation Of Leaf Structure To Physical Factors, Edith Schwartz Clements

School of Biological Sciences: Faculty Publications

The leaf, as the seat of important physiological functions of the plant, and because of its modification by external factors, has long been a fruitful subject for investigation. As a rule, however, investigators have confined themselves solely to the histology and morphology of the leaf, independent of its relations to physical factors. Where the latter have been considered at all, it has been in a more or less general way, or undue importance has been assigned to one or another of the physical factors, and others have been ignored entirely. In no case have they been carefully measured. The aim …

The Grasses Of Nebraska, Charles E. Bessey, Robert Bolin , Depositor

School of Biological Sciences: Faculty Publications

Dr Bessey was the Nebraska State Botanist and Professor of Botany at University of Nebraska. This report contains a classification list of grasses found in the state and brief comments on the usefulness of the various grasses.

A Second Report Upon The Native Trees And Shrubs Of Nebraska, Charles E. Bessey, Robert Bolin , Depositor

School of Biological Sciences: Faculty Publications

Dr. Bessey was then Nebraska State Botanist and “Professor of Botany, State University, Lincoln Nebraska.” The State University is now called that University of Nebraska–Lincoln. This document was published as a contribution to the knowledge of the native woody plants of the state. Several reports had been published previously each containing additions and corrections. This report contains a “Special Request” that asked readers around the state to send samples of native trees and shrubs to the author.

The report contains a classification list of the various trees and shrubs along with information about where they can be found. A table …