Kenneth E. Kemp

Effects of habitat on dickcissel abundance and nest success in conservation reserve program fields in Kansas

Declining avian populations in the Midwest have increased interest in various aspects of grassland habitats and their effects on grassland birds. We studied the effects of vegetation characteristics, woody field edges, and surrounding land use on abundance and daily nest survival of the dickcissel (Spiza americana) in Conservation Reserve Program (CRP) fields in northeastern Kansas. We observed 873 dickcissels during surveys on 11 CRP fields during the summers of 1994 and 1995. In those fields, we located 186 dickcissel nests of which 13.2% were successful in 1994 and 14.9% were successful in 1995. The vertical density of vegetation in CRP fields, wooded area surrounding the fields, and amount of woody edge bordering fields were associated with dickcissel abundance (P = 0.001). Live and dead canopy cover and litter cover were associated with daily nest survival (P = 0.005). Therefore, the habitat quality of CRP fields for dickcissels might be enhanced by modifying vegetation characteristics. The outcome of any modifications of CRP habitat for dickcissels should be judged on changes in the number and success of their nests rather than on the abundance of birds.

Effect of Commercially Available Plant-Derived Essential Oil Products on Arthropod Pests

ABSTRACT Plant-derived essential oil products, in general, are considered minimum-risk pesticides and are exempt from Environmental Protection Agency registration under section 25 (b) of the Federal Insecticide Fungicide and Rodenticide Act. However, many of the plant-derived essential products available to consumers (homeowners) have not been judiciously evaluated for both efficacy and plant safety. In fact, numerous plant-derived essential oil products labeled for control of arthropod pests have not been subject to rigorous evaluation, and there is minimal scientific information or supporting data associated with efficacy against arthropod pests. We conducted a series of greenhouse experiments to determine the efficacy and phytotoxicity of an array of plant-derived essential oil products available to consumers on arthropod pests including the citrus mealybug, Planococcus citri (Risso); western flower thrips, Frankliniella occidentalis (Pergande); twospotted spider mite, Tetranychus urticae Koch; sweetpotato whitefly B-biotype, Bemisia tabaci (Gennadius); and green peach aphid, Myzus persicae (Sulzer). Although the products Flower Pharm (cottonseed, cinnamon, and rosemary oil) and Indoor Pharm (soybean, rosemary, and lavender oil) provided >90% mortality of citrus mealybug, they were also the most phytotoxic to the coleus, Solenostemon scutellarioides (L.) Codd, plants. Both GC-Mite (cottonseed, clove, and garlic oil) and Bugzyme (citric acid) were most effective against the twospotted spider mite (≥90% 0ortality). However, SMC (canola, coriander oil, and triethanolamine), neem (clarified hydrophobic extract of neem oil), and Bug Assassin (eugenol, sodium lauryl sulfate, peppermint, and citronella oil) provided >80% mortality. Monterey Garden Insect Spray, which contained 0.5% spinosad, was most effective against western flower thrips with 100% mortality. All the other products evaluated failed to provide sufficient control of western flower thrips with <30% mortality. In addition, the products Pest Out (cottonseed, clove, and garlic oil), Bang (Pipereaceae), and Fruit & Vegetable Insect Spray (rosemary, cinnamon, clove oil, and garlic extract) had the highest flower (transvaal daisy, Gerbera jamesonii [H. Bolus ex Hook.f]) phytotoxicity ratings (≥4.5 of 5) among all the products. None of the plant-derived essential oil products provided sufficient control of sweetpotato whitefly B-biotype or green peach aphid 7, 14, and 21 d after application. Furthermore, the products Bug Assassin (eugenol, sodium lauryl sulfate, peppermint, and citronella oil) and Sharpshooter (sodium lauryl sulfate and clove oil) were phytotoxic to the poinsettia, Euphorbia pulcherrima Willd. ex Klotzsch, plants. This study is one of the first to quantitatively demonstrate that commercially available plant-derived essential oil products vary in their effectiveness against certain arthropod pests stated on the label and are phytotoxic.

Avian Abundance in CRP and Crop Fields during Winter in the Midwest

Abstract We compared the abundance and species composition of birds in Conservation Reserve Program (CRP) fields with the same aspects in row-crop fields during the winter (January and February) over several years (1992–1995) for six midwestern states (Indiana, Iowa, Kansas, Michigan, Missouri and Nebraska). Field techniques were standardized in all states. CRP fields consisted of either permanent introduced grasses and legumes (CP1) or permanent native grasses (CP2), and the plant species seeded in CRP fields differed within and among states. Vegetation characteristics of CRP fields varied considerably from state to state, but vertical density and total canopy cover (primarily grasses) were particularly high in Nebraska. Mean annual total bird abundance ranged from 0.1 to 5.1 birds per km of transect in CRP fields and from 0.1 to 24.2 in row-crop fields. The total number of bird species recorded in CRP fields in the six states ranged from 6 to 32; the range for row-crop fields was 8 to 18. The most abundant species in CRP fields differed among states but included the ring-necked pheasant, American tree sparrow, northern bobwhite, dark-eyed junco and American goldfinch. The most abundant species in row-crop fields included the horned lark, American tree sparrow, European starling, mourning dove, lapland longspur, meadowlarks and Canada goose. Some of the most abundant bird species wintering on CRP fields have been undergoing long-term population declines, thus this program has the potential to mitigate population losses.

SPRING BURNING : RESULTING AVIAN ABUNDANCE AND NESTING IN KANSAS CRP

Spring burning is used to control invasion by woody vegetation of rangelands in eastern Kansas and also of Conservation Reserve Program (CRP) fields planted to native grasses. We measured the effects of spring burning of CRP fields on vegetation structure and avian populations in northeastern Kansas during the summers of 1992 through 1995. Several vegetation characteristics differed between burned and unburned CRP fields in May, but few differed in July. Mean avian abundance on burned CRP fields was 5.6 birds km-1 of survey transect, significantly less (P < 0.01) than the 8.6 km-1 on unburned fields. The avian-assemblages on burned and unburned fields differed more in May/June [Morisitas Index to Similarity (MIS) = 0.86] than in June/July or July/August (MIS = 0.98 and 0.97, respectively). Avian species richness ranged from 12 to 21 on burned fields and from 10 to 19 on unburned fields. A total of 27 nests was found on burned fields, significantly less (P < 0.01) than the 372 found on unburned fields. The 22.2% nesting success on burned fields was not significantly different (P = 0.205) than the 34.1% success on unburned fields. Spring burning reduced bird-nest numbers in the summer of the same year, but did not reduce significantly (P = 0.235) the number of nests found in those fields the following summers nor the abundance of birds or nesting success. Avoidance of annual burning would reduce adverse impacts on bird populations relying on CRP fields for nesting habitat.

Aboveground counts of black-tailed prairie dogs: temporal nature and relationship to burrow entrance density

Black-tailed prairie dog (Cynomys ludovicianus) colonies are important to many vertebrate populations in the shortgrass prairie ecosystem. Because it is often desirable to assess black-tailed prairie dog populations, and indirect methods generally are more economical than direct counts, we tested whether aboveground counts of black-tailed prairie dogs were related to burrow entrance densities. Higher densities of burrow entrances have been assumed to reflect higher prairie dog densities. We determined if maximum aboveground counts of black-tailed prairie dogs differed temporally in morning and evening in southwestern Kansas, compared maximum aboveground count data with burrow entrance densities, and evaluated the effect of juvenile prairie dog emergence on the temporal nature of morning and evening maximum above-ground counts

WILL CONVERSION OF CONSERVATION RESERVE PROGRAM (CRP) LANDS TO PASTURE BE DETRIMENTAL FOR GRASSLAND BIRDS IN KANSAS

-The Conservation Reserve Program (CRP) was established by the 1985 Food Security Act (Farm Bill). Unless renewed, most CRP contracts will expire in 1997 and up to 70% of CRP fields in Kansas may be converted to pasture. We compared avian use of CRP areas with that of pasture to determine if such conversion would be detrimental to grassland birds. Data on vegetative structure, avian abundance, and avian reproductive success were collected on five CRP fields and five pastures during summer 1993. Pastures had significantly greater vegetative cover and CRP fields had more bare ground. Vegetation was significantly taller in CRP fields late in the summer. Total avian abundance and that of dickcissels, grasshopper sparrows, meadowlarks, brown-headed cowbirds and upland sandpipers were greater in pastures than in CRP fields. Reproductive success and rates of nest parasitism by brownheaded cowbirds did not differ between the habitats, but nests were more numerous in grazed pastures. If the CRP is not reauthorized in the 1995 Farm Bill and most of the Kansas land currently enrolled in CRP is converted to pasture, the conversion probably will not be detrimental to grassland bird populations if the land is moderately grazed.

Effect of Pesticides on Adult Rove Beetle Atheta coriaria (Coleoptera: Staphylinidae) Survival in Growing Medium

ABSTRACT The rove beetle Atheta coriaria (Kraatz) (Coleoptera: Staphylinidae) is a natural enemy (biological control agent) commercially available for control of certain greenhouse insect pests, including fungus gnats, shore flies, and thrips. This study assessed the compatibility of pesticides (insecticides and fungicides) used in greenhouses with A. coriaria adults. Treatments were applied to 473-ml deli squat containers half-filled with a growing medium. We evaluated the effects of the pesticides when releases of A. coriaria adults were performed both before and after application of the designated pesticide solutions. All three of the neonicotinoid-based insecticides (clothianidin, dinotefuran, and thiamethoxam) were directly harmful to A. coriaria adults with ≤3.2 adults recovered (out of 20) among all three treatments across all experiments. In addition, the organophosphate insecticide chlorpyrifos at the low (0.25 fl oz/100 gal) and high (0.50 fl oz/100 gal) label rates; the plant-derived essential oil product (Indoor Pharm) containing soybean and rosemary oil; and the insecticide/miticide chlorfenpyr were directly harmful to A. coriaria adults with recovery rates ≤8.6 (out of 20) among all the treatments. The fungicides (azoxystrobin, fosetyl-aluminum, and mefenoxam) were not directly toxic to A. coriaria adults, with ≥17.7 adults recovered (out of 20) across all experiments. The insecticides (Bacillus thuringiensis subsp. israelensis, flonicamid, Metarhizium anisopliae strain52, and spinosad) and insect growth regulator azadirachtin were also not directly toxic to A. coriaria adults. Furthermore, many of these same treatments did not inhibit the ability of adult A. coriaria to consume fungus gnat (Bradysia sp. nr. coprophila) larvae in a feeding behavior experiment. Although the neonicotinoid-based insecticides were directly harmful to adult A. coriaria, when adults were released 48, 72, or 96 h after application, survival increased dramatically over time. This study has quantitatively demonstrated that certain pesticides (both insecticides and fungicides) are compatible with and can be used along with A. coriaria in systems that use this natural enemy to manage fungus gnat larvae.

Helminth parasites of lesser prairie-chicken Tympanuchus pallidicinctus in southwestern Kansas: incidence, burdens and effects

We conducted a 3-year study of helminth parasites to assess their effect on the lesser prairie-chicken Tympanuchus pallidicinctus. Helminth parasites were found in most of the examined wild prairie chicken carcasses: 95% had eye worm Oxyspirura petrowi, 92% had stomach worm Tetrameres sp., and 59% had caecal worm Subulura sp. Few parasite burdens or incidences of infection were related to prairie chicken body mass, gender, age or season of collection. Droppings from transmitter-equipped prairie chickens were examined for parasite eggs and the data were used to determine which free-ranging prairie chickens harboured parasites. Telemetry data from 46 heavily parasitized and 52 lightly parasitized or parasite-free prairie chickens indicated no difference between mean daily movements, monthly home ranges, clutch sizes, nest success or survival. No adverse impacts were evident in the lesser prairie-chicken population from the incidences or burdens of the helminth parasites found in our study.

Factors influencing mourning dove nest success in CRP fields

Mourning doves (Zenaida macroura) nest primarily in trees. However, ground nesting is prevalent in the Great Plains region where mourning dove numbers have increased since the mid 1980s when the Conservation Reserve Program (CRP) was initiated. We monitored mourning dove nest success in CRP fields in Kansas during 1994 and 1995 to determine if that habitat could be a source for the increased numbers. Mourning dove nest success averaged 56% (n = 90) in our CRP fields. Daily nest survival rates in CRP fields were associated positively with height of live vegetation (P = 0.011) and negatively with percent grass cover (P = 0.001) and percent live vegetation cover (P = 0.005). Management practices that produce sparse overall cover but tall vegetation height may increase mourning dove nest success in CRP fields.

Sensory characteristics of grain sorghum hybrids with potential for use in human food

ABSTRACT Descriptive sensory characteristics were measured for porridges made from flour samples collected from the 1996 Kansas feed grain sorghum performance tests and from commercial food grain sorghum samples. Totals of eight and 11 sensory attributes characterized the feed grain and food grain samples, respectively. Two screenings provided descriptive sensory data for univariate and multivariate analyses. Four feed grain samples from the performance tests and seven food grain samples were identified as low in astringency and bitterness; six of these were used in 100% sorghum flour muffins to determine consumer acceptability. Flavor acceptability of muffins was perceived as equal, and appearance was an important factor for acceptance. Optimization of all sensory attributes for each specific product is needed to increase acceptability of grain sorghum in consumer products.