Purple nutsedge (Cyperus rotundus) is a major warm season weed in turfgrass, landscape and agricultural settings. It’s long term persistence is achieved in part by (1) the production of tubers with numerous growing points (2) the ability to produce multiple plants from basal bulbuls at the soil level and (3) the tolerance to defoliation and/or soil cultivation. In turf, purple nutsedge can tolerate almost any mowing regime, and is competitive (in it's growth habit) with turfgrasses. Imazaquin (IMAGE) herbicide has been commercially available in the turfgrass market for almost 12 years for use in warm season turfgrasses for the control of purple nutsedge. Research conducted in the late 1980's at the University of Arizona showed that Image (EC formulation) provided adequate control of purple nutsedge when (1) multiple applications were applied 25 days apart (2) at the 0.50 lb. ai./a rate. In this scenario 98% nutsedge control was achieved (on 100 % nutsedge plots, mowed weekly at 2.5 inches). Repeat applications were still necessary after regrowth (presumably from growing points from underground nutlets). These results were achieved using the 1.5 EC (emulsifiable concentrate formulation). A new test was conducted in 1999, evaluating both the 1.5 EC and 70 DG (dispersible granule) formulations applied at two rates (0.375 lb. ai./a. and 0.50 lb. ai./a). Mean percent weed control on the three evaluation dates of August 17, August 29 and September 16 ranged from 25% to 32%, 50% to 68% and 55% to 75%, respectively. These dates represent the time intervals of 18 DAT/1, 30 DAT/1 and 17 DAT/2. On all three evaluations dates (where measured), the degree of injury, color and percent nutsedge infestation level was significant for the overall "treatment" effect at P=0.05, or less. (Tables 1,2). Actual percent weed control (based on the mean of control plots) was significant on August 29 (30 DAT/1) and on September 16 (17 DAT/2:47 DAT/1). Maximum weed control of 75% was achieved by the EC @ 0.50 lbs. ai./a. at 17 days after the second application. Percent weed control for the DG @ 0.50 lbs. ai./a. was greatest (61%) at that time also.

Poa annua (annual bluegrass) is a major weed problem in winter turfs. It is a cosmopolitan and well adapted weed in most turfgrass settings. Cultural management programs to control or eliminate Poa annua are either limited or unsuccessful. Sulfentrazone herbicide was applied to perennial ryegrass turf (as overseeded bermudagrass) which had high levels of Poa annua infestation (45%-75%) at 0.125, 0.250 and 0.375 lb. AI/A. There was essentially a limited response of Poa annua to Sulfentrazone at these rates when applied on March 7, 1997. EMBARK LITE (Mefluidide) was applied once at 0.125 lb. AI/A and caused some initial discoloration to the turf at 10 DAT. At 25 DAT percent control of Poa annua (seed heads) reached 90% or greater which declined to 58% on April 15 (40 DAT). Turfgrass color was enhanced from the single application of Mefluidide at 25 and 40 DAT on golf course rough turf maintained at a mowing height of 1.50 inches. Sulfentrazone exhibited minimal or no effect on Poa annua when applied as a post emergence treatment.

Herbicides applied for post-emergence control of wild parsley differed in turf injury and weed control. All products tested required multiple applications (21 days apart) to attain acceptable weed control levels. Weedone (2, 4-D) has the quickest, highest, and longest lasting amount of weed control. Weedone (2, 4-D) caused minimal injury to the common bermudagrass turf. Bromoxynil at the low rate of 2.0 lbs. ai/a caused minimal injury to the turf, but provided low levels of weed control. Bromoxynil at the high rate of 3.0 lbs. ai/a caused considerable injury to the turf and moderate to high weed control for about one month, followed by weed recovery. MCPP caused slight initial injury to common bermudagrass and moderate to good weed control (71%-92%) from 7 to 35 days after the second treatment. Weed control was slower to achieve than that of the Weedone treatments. Confront herbicide (trichlopyr and clopyralid) caused slight to moderate initial injury to the turf (more so at 2.0 than at 1.0 pint/product/acre) as well as noticeable necrosis and decreased color of the common bermudagrass up to 21 days after the second application. Confront at the 2.0 pint/acre rate reached weed control levels of 90%-97% at 21 and 35 days after the second application, respectively. At the low rate of 1.0 pint/acre, a maximum of 83% weed control was achieved at the close of the test. Quadmec (applied three weeks later at each respective application date than all other treatments) produced moderate necrosis in the bermudagrass after the initial application, which eventually recovered. However, the turfgrass color was lower in rank (lighter) than most other treatments and was similar to that of the untreated controls. Quadmec achieved 96% control by the close of the test on July 2, 1999 (14 days after the second application). All treatments include 0.5% v/v Silwet surfactant. When applied alone, Silwet produced a small level of weed control, which peaked at 36% at 14 days after the second treatment.

Seed head production from Poa annua is problematic on winter turfs, whether they are overseeded or not. Flowering culms are unsightly, prevent a uniform surface, and insure a continuous crop of seeds for the future. A field test was conducted to evaluate the effects of PROXY and a PROXY/PRIMO PGR tank mix for seed head control. Treatments were applied on three different dates in order to evaluate the degree of response of treatments and help define treatment window applications for future programs. PROXY when applied alone at 5 ounces/product/M produced a maximum of 60% seed head control at 26 days after a single application on February 15, and 83% seed head control at 27 days after a single application on March 1. A tank mix of PROXY/PRIMO (5.0/0.25 ounces/product/M) generally produced greater seed head control than PROXY alone. The tank mix produced seed head control effects quicker, greater, and longer than PROXY alone. Seed head suppression and percent seed head control was greatest when products were applied initially on either February 15 or March 1, 2001. PROXY/PRIMO produced the darkest color turf when applied on either February 15 or March 1. At least three tank mixes seem to be needed, applied monthly to suppress/control seed heads throughout the winter/spring season.

Poa annua or annual bluegrass is a cosmopolitan winter annual weed in turfgrass systems. A field test was conducted to evaluate the effects of sulfentrazone herbicide, both with and without the fall overseeding practice on bermudagrass in the desert. Sulfentrazone was applied three days before overseeding at 0.125, 0.187, 0.25, 0.375, 0.5 and 0.625 lbs.AI/A. Percent Poa infestation levels were dramatically less on overseeded (perennial ryegrass added) turf throughout the entire test period than non-overseeded (dormant bermudagrass) turf. For non-overseeded turf, sulfentrazone provided a maximum of 74% weed control at November 1997, 68% in December, and 25% by March 1998 at the highest application rate of 0.625 lbs./A. For overseeded (perennial ryegrass) turf, the highest level of weed control was achieved for sulfentrazone at the 0.625 lbs./A rate, which was 68% in April. The practices of overseeding and sulfentrazone applications provided the greatest weed control, however, different rate/timing regimes should be investigated to increase efficiency.

Sulfentrazone was applied to a highly infested purple nutsedge groundcover as either single or double combination (split) applications for initial evaluation for weed control during the summer of 1996. One time single applications at 0.125 lb. AI/A resulted in 15% or less control, from 10 to 64 days after treatment (DAT). Nutsedge control from 0.25 lb. and 0.38 lb. AI/A treatments were not significantly different from each other (ranging in 10% difference or less) but was greater than the low rate 0.125 lb. AI/A. Single applications of imazaquin and halsulfuron (at known label rates) had better control than sulfentrazone at the rates tested here when tested as single applications. Single applications at 0.50 lb. AI/A appear warranted for sulfentrazone. Split (multiple) applications greatly enhanced the activity of Sulfentrazone at the two higher split rate treatments, both which resulted in a total application of 0.50 lb. AI/A total. The 0.375/0.125 split application had slightly better control than the 0.250/0.250 split treatments. Split applications of imazaquin or halsulfuron at known label rates resulted in slightly higher control. All plots experienced re-growth. Based on these results, sulfentrazone does have activity against purple nutsedge. Additional treatments in a new and different rate structure appear warranted to increase initial control and longevity of effect.

Sulfentrazone herbicide was applied to a SR1020 creeping bentgrass putting green (5/32") on October 15, 1996 and again on March 4, 1997 at the rates of 0.125, 0.250 and 0.375 lb. AI/A. Betasan was included at the standard rate of 5.6 ounces of product/1000 ft2. Turf response to sulfentrazone was mostly linear with application rate, with higher application rates causing more damage to the turf. Responses occurred quicker in the fall (by 3 DAT) compared to late winter (7DAT). Magnitude of injury was also somewhat less in the late winter than in the fall, although rank responses were still rate dependent for sulfentrazone treated creeping bentgrass turf. Applied rates of 0.250 and 0.375 lb. AI/A were deleterious and not acceptable for putting green quality turf. A marginal (acceptable) response occurred overall at the 0.125 lb. rate. Betasan applied at 5.6 ounces product/1000 ft², caused no visible damage to the turf in the fall and was similar in response to sulfentrazone in the spring at the 0.125 lb. AI/A (repeat) application rate.

A seed sowing experiment was conducted in a mixed secondary woodland on acidic soils in NE Germany with <i>Melampyrum pratense</i>, an annual ant-dispersed forest herb which lacks a natural population in the study area, but is abundant in similar habitats. Each set of 300 seeds was sown within one square metre at three sites in 1997, and the development of the populations was recorded from 1998 onward. Additionally, seed fall patterns were studied in a natural population by means of adhesive cardboard. All trials resulted in the recruitment of populations, which survived and increased in both individual number and area, up to the year 2001. Thus, local distribution of <i>Melampyrum pratense</i> is dispersallimited. Total individual number increased from 105 to 3,390, and total population area from 2.07 to 109.04 m². Migration occurred in all directions. Mean migration rate was 0.91 m per year, and the highest migration rate was 6.48 m. No individual was recorded beyond 7.63 m from the centres of the sawn squares after three years, suggesting exclusive short-distance dispersal. As primary dispersal enables only distances of up to 0.25 m, ants are presumed to be the main dispersal vectors. Despite differences in individual number and colonization patterns, migration rates did not differ significantly between the populations, but were significantly higher in 2001 due to an increased population size. Colonization patterns were characterized by a rapid, negative exponential decrease of population density with increasing distance from the sown plot, suggesting a colonization by establishment of more or less isolated outposts of individuals and a subsequent gradual infill of the gaps between. My results resemble myrmecochorous dispersal distances in temperate woodlands, and migration rates and patterns across ecotones from ancient to recent deciduous forests. They may function as a colonization model of <i>Melampyrum pratense</i> after accidental long-distance dispersal.

Made available in DSpace on 2015-03-26T13:23:54Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1051701 bytes, checksum: aaea4730523b61480fcd7621b67f8f7e (MD5) Previous issue date: 2014-02-10 / The Cordia verbenacea species, known as Erva Baleeira has been mostly studied by its pharmacologic properties since it has a curative potential as an anti-inflammatory, an analgesic, and an anti-ulcer gene; however, the effect of the drying process on this species has not been analyzed yet. The main purpose of this work was to evaluate the influence of the drying air temperature in the quantity and quality of the cordia s essential oil; therefore, in order to reach that objective, some leaves of this plant species were collected during august of 2013 from the Experimental Vale do Piranga farm, which belongs to EPAMING. Consequently, the vegetal material was carefully selected and dried. The stablished temperatures for that process were 40, 50, 60, and 70 Celsius degrees, with the aim of evaluating the quantity and quality of the essential oil obtained from dried leaves compared to fresh leaves oil. A Clavenger type apparatus was used for the essential oil extraction from cordia leaves and afterward, the appropriate gas-chromatographic analysis was performed (GC-MS-GCFID). In summary, the results of the study allow one to conclude that the content of the cordia s essential oil was affected by the drying air temperatures while the one obtained from fresh leaves remained unaltered. In addition, between all the active principles found, only &#945;- humulene had a deducted concentration due to the influence of the drying process compared to the fresh plant. / La especie Cordia verbenacea, conocida como Erva Baleeira , ha sido objeto de estudio por sus propiedades farmacológicas, confirmándose su potencial como anti-inflamatorio, analgésico, e anti-ulcero génico, sim embargo aún no se ha estudiado el efecto que tiene el proceso de secado en esta especie. El objetivo de este trabajo fue evaluar la influencia que tiene la temperatura del aire de secado en la cantidad y calidad de aceite esencial de cordia, para cumplir dicho objetivo, hojas de esta especie fueron obtenidas de un cultivo de la hacienda Experimental Vale do Piranga, perteneciente a EPAMIG, en el mes de agosto del 2013, posteriormente el material vegetal fue seleccionado y llevado al secado. Las temperaturas establecidas fueron de 40, 50, 60 y 70 °C y de esta manera evaluar la cantidad y calidad del aceite esencial obtenido de hojas secas en comparación con el aceite obtenido de muestras frescas. En la extracción de aceite esencial de hojas de cordia, se usó un aparato tipo Clevenger y posteriormente se realizó el respectivo análisis cromatografico a gas (GC-MS GCFID). Puede concluirse que el contenido de aceite esencial fue afectado por las temperaturas del aire de secado, respecto al aceite esencial obtenido de hojas frescas y que dentro de los principios activos encontrados, solamente el &#945;-humulene tuvo su concentración disminuida por influencia del proceso de secado cuando comparado con la planta fresca.

The impact of a bark beetle outbreak, and the following sanitation management actions, on the mountain spruce forest in the central part of the Šumava Mountains were compared after twelve years of development. The survey was focused on natural regeneration of trees and herb-layer vegetation.