A Study of the Relationship Existing Between Certain Insects and Some Native Western Kansas Forbs and Weedy Plants

To the casual observer perhaps no sight could be more commonplace than that of an insect alighting upon a Kansas sunflower. But the relationship which exists between plant and insect is a matter which is often unknown even to the specialist. And yet a lack of understanding of these relationships has at times resulted in inconvenience, loss, and even in calamity. To determine some of the relationships which certain insects bear to some of our native western Kansas forbs and weedy plants is the purpose of this study. Included in the investigation are those insects which spend at least a part of their lives beneath the epidermis of the plant root, stem, or leaf or within the inflorescence, fruits, or galls produced by the plants. Insects which may consume internal as well as external parts but which do not at some time inhabit the plant body or its products are excluded from consideration. During the summer of 1941 in connection with a course in plant ecology the problem presented itself to determine the fate of the seeds produced by the white beard-tongue, (Pentstemon albidus). The final tabulation of the results of the study showed that insects destroyed approximately 55,% of the seeds produced within two months after flowering. An investigation was then begun to determine which insects were probably most effective in destroying the seeds. Large numbers of plants were dug and carefully examined. It was found that two insects commonly inhabit the seed capsules. These insects were studied in some detail and their life cycles observed. This proved so interesting that a study of additional native plants and weeds was determined upon in order to ascertain if possible which insects most commonly affect internal parts of these plants. In each case a superficial study of the plants was made in the field. Among large numbers of plants examined those were selected for special study and dissection which gave indications of insect infestation. These were dug and taken to the laboratory and completely dissected. Each root, stem, petiole, leaf, flower, fruit, and gall was carefully examined and all parts which might harbor insects were fully dissected. Insects found were kept and cultured for further observation. It was found extremely difficult to keep certain burrowing types alive because of the attacks of molds and other fungi when containers were kept closed. Plants were collected from 15 different locations in western Kansas all within a radius of about 80 miles to the east, north, west, or southwest of Hays. The author acknowledges his indebtedness to Dr. George M. Robertson, Dr. F. W. Albertson, and Dr. R. E. Bugbee for suggestions, guidance, criticism, and encouragement in the progress of the work and in the preparation of this paper; to John Launchbaugh for plants collected from two areas; and to Dr.