Search Results

You are looking at 11 - 20 of 41 items for :

  • black-eyed susan x
  • Refine by Access: All x
Clear All
Free access

Jeffrey F. Derr

Tolerance of transplanted black-eyed Susan (Rudbeckia hirta var. pulcherrima Farw.), lanceleaf coreopsis (Coreopsis lanceolata L.), shasta daisy (Chrysanthemum × superbum Bergmans ex. J. Ingram), purple coneflower [Echinacea purpurea (L.) Moench.], and blanket flower (Gaillardia aristata Pursh) to preemergence herbicides was evaluated in container trials. Herbicides were applied at the maximum use rate and twice the maximum use rate. Dithiopyr, pendimethalin, and prodiamine provided excellent control of spotted. spurge (Euphorbia maculata L.) and yellow woodsorrel (Oxalis stricta L.) with little injury to the five herbaceous perennials. DCPA, oxadiazon, and metolachlor were tolerated by all treated species, but these chemicals provided lower control of one or both weed species. Oryzalin, isoxaben + trifluralin, and napropamide caused unacceptable injury and shoot fresh-weight reductions in some of the perennials at one or both application rates. Chemical names used: dimethyl 2,3,5,6-tetrachloro-1,4-benzenedicarboxylate (DCPA); S,S-dimethyl 2-(difluoromethyl) -4-(2 -methylpropyl)-6-trifluoromethyl-3,5-pyridinedicarbothioate(dithiopyr);N-[3-(1-ethyl-1-methylpropyl)-5-isoxazolyl]-2,6-dimethoxybenzamide(isoxaben); 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide(metolachlor);N,N-diethyl-2-(l-naphtha1enenyloxy) propanamide(napropamide);4-(dipropylamino)-3,5-dinitrobenzenesulfonamide (oryzalin);3-[2,4-dichloro-5-(1-methylethoxy)phenyl]-5-(1,1-dimethylethy1)-l,3,4-oxadiazol-2-(3H)-one (oxadiazon); N-(1-ethylpropyl) -3,4-dimethyl-2,6-dinitrobenzamine (pendimethalin); N,N-di-n-propyl-2,4-dinitro-6-(trifluoromethyl)-m-phenylenediamine (prodiamine); 2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)benzamine (trifluralin).

Free access

Jyotsna Sharma

Because of thousands of years of adaptation to the native climate, prairie forbs (“wildflowers”) present a large potential for their use in beautification projects along roadsides, in large backyards, and in nature centers. Vegetation in abandoned, naturally revegetated, grass-dominated areas can be managed to encourage a forb-dominated stage. Two grass herbicides [sethoxydim (PoastTM) and fluazifop (Ornamec-170TM)], three burning treatments (winter, early spring, and late spring), and two mowing treatments (fall and late spring) were tested to determine their effect on forb cover and species diversity in a mid-successional tallgrass prairie. One application of either of the herbicides, at the time of recommended growth stage of target grasses, changed species composition significantly (80% forbs vs. 46% forbs in control plots; P < 0.05) in favor of showy forbs. Species diversity of sprayed plots was relatively low, however. Burning was the next best alternative (averaging 63% forbs) that also resulted in highest species diversity. Fall and late spring mowing reduced cover of forbs (32%) and species diversity to levels lower than those found in control plots. Cover of Solidago canadensis (tall goldenrod) in sethoxydim-treated plots increased to 22.8% compared to 2.5% in control plots. Cirsium discolor (pasture thistle) and Rudbeckia hirta (black-eyed susan) also increased significantly in response to herbicide treatments.

Free access

Jillene R. Summers, Gail R. Nonnecke, Cynthia A. Cambardella, Richard C. Schultz, and Thomas M. Isenhart

Improving soil quality and suppressing weeds are two challenges facing strawberry growers. Cover crops, such as perennial ryegrass (Lolium perenne) and sorghum-sudangrass (Sorghum sudanense), have been used in rotation with strawberry in the Midwest. The objective of the field study was to investigate the effects of various cover crops on soil quality and weed populations for strawberry production. The experiment was established in 1996 at the Iowa State Univ. Horticulture Station, Ames, in plots that previously were planted continuously in strawberry for 10 years. Nine treatments were arranged in a randomized complete-block design with three replications. Treatments included cover crops of Indian grass (Sorghastrum avenaceum), switchgrass (Panicum virgatum), big bluestem (Andropogon gerardii), black-eyed susan (Rudbeckia hirta), marigold (Tagetes erecta `Crackerjack'), sorghum-sudangrass, perennial ryegrass, strawberry (Fragaria ×ananassa `Honeoye'), and bare soil (control). Data from 1998 showed that both annual and perennial cover crops were established more readily (higher treatment-plant populations and less weed populations) than in 1997. Water infiltration rates were highest in bare soil plots and lowest in P. virgatum plots. Bare soil plots and S. sudanense plots had the lowest percent soil moisture.

Full access

D. Bradley Rowe, Michael A. Monterusso, and Clayton L. Rugh

Green roof technology in the United States is in the early development stage and several issues must be addressed before green roofs become more wide-spread in the U.S. Among these issues is the need to define growing substrates that are lightweight, permanent, and can sustain plant health without leaching nutrients that may harm the environment. High levels of substrate organic matter are not recommended because the organic matter will decompose, resulting in substrate shrinkage, and can leach nutrients such as nitrogen (N) and phosphorus (P) in the runoff. The same runoff problems can occur when fertilizer is applied. Also, in the midwestern U.S., there is a great deal of interest in utilizing native species and recreating natural prairies on rooftops. Since most of these native species are not succulents, it is not known if they can survive on shallow, extensive green roofs without irrigation. Five planting substrate compositions containing 60%, 70%, 80%, 90%, and 100% of heat-expanded slate (PermaTill) were used to evaluate the establishment, growth, and survival of two stonecrops (Sedum spp.) and six nonsucculent natives to the midwestern U.S. prairie over a period of 3 years. A second study evaluated these same plant types that were supplied with four levels of controlled-release fertilizer. Both studies were conducted at ground level in interlocking modular units (36 × 36 inches) designed for green roof applications containing 10 cm of substrate. Higher levels of heat-expanded slate in the substrate generally resulted in slightly less growth and lower visual ratings across all species. By May 2004, all plants of smooth aster (Aster laevis), horsemint (Monarda punctata), black-eyed susan (Rudbeckia hirta), and showy goldenrod (Solidago speciosa) were dead. To a lesser degree, half of the lanceleaf coreopsis (Coreopsis lanceolata) survived in 60% and 70% heat-expanded slate, but only a third of the plants survived in 80%, 90%, or 100%. Regardless of substrate composition, both `Diffusum' stonecrop (S. middendorffianum) and `Royal Pink' stonecrop (S. spurium) achieved 100% coverage by June 2002 and maintained this coverage into 2004. In the fertility study, plants that received low fertilizer rates generally produced the least amount of growth. However, water availability was a key factor. A greater number of smooth aster, junegrass (Koeleria macrantha), and showy goldenrod plants survived when they were not fertilized. Presumably, these plants could survive drought conditions for a longer period of time since they had less biomass to maintain. However, by the end of three growing seasons, all three nonsucculent natives also were dead. Overall results suggest that a moderately high level of heat-expanded slate (about 80%) and a relatively low level of controlled-release fertilizer (50 g·m-2 per year) can be utilized for green roof applications when growing succulents such as stonecrop. However, the nonsucculents used in this study require deeper substrates, additional organic matter, or supplemental irrigation. By reducing the amount of organic matter in the substrate and by applying the minimal amount of fertilizer to maintain plant health, potential contaminated discharge of N, P, and other nutrients from green roofs is likely to be reduced considerably while still maintaining plant health.

Full access

survey of the major apple-producing states lists application rate and use pattern for the most frequently applied preemergence and postemergence herbicides. BLACK-EYED SUSAN FROM DIFFERENT SEED SOURCES EVALUATED A commercial Texas

Full access

Gina M. Angelella, Laura Stange, Holly L. Scoggins, and Megan E. O’Rourke

performed to evaluate significant differences at the P ≤ 0.05 level. Only the plots with annual species bloomed during the first year, whereas all wildflower plots bloomed during the second year ( Table 1 ). Black-eyed Susan provided the greatest bloom

Full access

Douglas W. Tallamy

rivets. An airplane could lose some rivets before a wing fell off the plane, and an ecosystem could lose some species before it suffered a measurable loss in productivity. Generalist pollinators provide an example of species redundancy. A black-eyed susan

Free access

Ariana P. Torres and Roberto G. Lopez

visible inflorescence to flower by 43 d in the pansy orchid ( Zygopetalum Redvale ‘Fire Kiss’), but flower longevity also decreased ( Lopez and Runkle, 2004 ). In tick seed ( Coreopsis grandiflora ), shasta daisy ( Leucanthemum ×superbum ), and black-eyed-susan

Full access

J. Ryan Stewart and Irene McGary

( Ratibida pinnata ), black-eyed susan ( Rudbeckia hirta ), and wild bergamot ( Monarda fistulosa ) ( Diboll, 2005 ; Nuzzo, 1978 ). These species represent only a fraction of the species currently found in high-quality prairie remnants in the midwestern

Full access

H. Chris Wien

Algonquin Books Chapel Hill, NC Wien, H.C. 2006a Growing black-eyed susan and sunflower out of season Growing Market 15 6 17 18 Wien, H.C. 2006b Can we grow cut flowers with longer stems? Cut Flower Qrtly. 18 3 32 33 Wien, H.C. 2007 Day-neutral sunflowers