Two studies were conducted to evaluate recycled newspaper mulch for landscape plantings. In the first study, two paper products (pellets and crumble) were tested at three depths. Application of either 25 or 50 mm provided excellent control of prostrate spurge. Of the four annuals grown, ageratum exhibited severe stunting of roots and shoots. In the second study, three annual species were mulched with the two recycled paper products applied at 25 mm each and adjusted with P at 0, 3.75, or 7.5 ppm to bind excess Al. When no P was added, ageratum growth was about half that of the control plants. Addition of P at either rate resulted in similar growth compared to control plants. Marigold and geranium were less affected by recycled paper mulch; however, when P was added growth was always similar to nonmulched control plants.
D. R. Smith, C. H. Gilliam, and J. H. Edwards
D.C. Fare, C.H. Gilliam, and G.J. Keever
Improved water use efficiency exists for plants grown in modified containers to minimize leaching and reduce irrigation frequency which subsequently reduces NO3-N leachate. Salvia splendens `Bonfire' and Impatiens wallerana `Pink' (super elfin hybrid) were potted in ProMix BX medium (Premier Brands, Inc., Stamford, CT) into nine container styles with modified drainage holes to determine leachate volume and quantify NO3-N leached. Three styles had four drainage holes on the container side with hole diameters of 0.5, 1.0, and 1.9 cm, respectively; three styles had four drainage holes on the container side and one drainage hole in the bottom center with hole diameters of 0.5, 1.0, and 1.9 cm, respectively; and three styles had one drainage hole in the bottom center with hole diameters of 0.5, 1.6, and 1.9 cm, respectively. Plants were hand watered when an individual container's medium reached 80% of container capacity. Leachate volume, irrigation frequency, and leachate NO3-N was reduced as drainage size hole decreased in size and number. Plant quality was similar among container modifications.
Charles H. Gilliam, Donna C. Fare, and Gary J. Keever
Little information is available on herbicide movement in soilless container media and subsequent movement in container leachate and container bed runoff. The objective of this study was to evaluate oxyfluorfen movement in irrigation water following application to container grown nursery crops in a commercial nursery. Oxyfluorfen levels in the container bed runoff were 9 to 27 times higher than those in container leachate during the 3 irrigations following herbicide application. Maximum oxyfluorfen level in the container leachate was 8.3 ppb following the first irrigation but declined to 2.0 ppb by the 12th irrigation. The oxyfluorfen level was still about 2.0 ppb following the 75th irrigation. Oxyfluorfen in the container bed runoff peaked at 99 ppb following the 3rd irrigation before declining to 67 ppb following the 6th irrigation.
Donna C. Fare, Charles H. Gilliam, and Gary J. Keever
Efficient usage of current water supplies is of great concern to container-nursery producers. Improving water management first requires knowledge of current commercial container production practices. In this study, irrigation distribution from overhead sprinklers was monitored at container nurseries to determine the distribution and the amount of irrigation applied during a typical irrigation cycle. Several nurseries surveyed had poorly designed irrigation systems; subsequently, irrigation distribution varied widely at sampling dates and within the growing-container block. Uniform distribution was achieved at some nurseries, but required careful monitoring of the irrigation system. Future water restrictions may force nurseries to improve water usage by changing irrigation delivery methods to minimize water use, resulting in reduced surface runoff and effluent from container nurseries.
J.H. Edwards, D.R. Smith, C.H. Gilliam, and D.C. Erbach
Excessive moisture is a problem in evaluating recycled paper products as mulch to replace other common mulch materials and in landscape and container uses. To isolate the water associated with soil and/or media, two recycled paper products, pellets or crumble, were used as mulches in trade gallon containers in a greenhouse. Pine bark, pellets, and crumble needed to obtain standard mulch depth were enclosed in plastic mesh. These mulches were placed in containers that contained 1 kg of a 7 pine bark : 1 sand media. All containers were saturated with tap water for 24 hours. Mulches were placed on each container and allowed to drain for 1 hour. Weights of media, mulch, and media and mulch were obtained every 24 hours for a total of 312 hours. Water content of the media was not influenced by any of the mulch treatments. Water content of the paper products was increased by a factor of two. Pine bark mulch water content was zero 96 hours after an initial dry down cycle began, while the water content of pellet and crumble were 100 and 90 cm of water. Total water content of the media plus the mulch was increased by 30% to 35% when compared to pine bark mulch alone. However, the increase was associated with the water content of the waste paper mulch.
K.M. Ryan, J.H. Edwards, C.H. Gilliam, and G.J. Keever
Blue color development in Hydrangea macrophylla is usually accomplished by applying Al as an alum drench. Drenches are applied during forcing 10–14 days after transplanting at a rate of 17,500 mg·L-1. Cultivars Blue Wave and Nikko Blue were used to evaluate if the Al contained in waste paper can provide the necessary Al for blue flower development. Two waste paper forms, pelletized and crumble, were used as surface mulches and as media amendments. The amendments were incorporated into the media at transplanting and mulches were applied either at transplanting or 28 days later. Alum drenching was initiated at transplanting as a control. Leachates were collected weekly using the VTEM. Total Al, electrical conductivity, and pH were determined on all samples. All waste paper treatments resulted in pink flowers in both cultivars. Leachate pH, from plants in this test, was >6.5. Aluminum concentration was greater than the 15 mg·L-1 Al needed for blue color development in flowers, but Al concentration decreased with time. Control of pH at the waste paper surface and in the media is critical for increasing the availability of labile Al for uptake by hydrangea.
D.C. Fare, C.H. Gilliam, P.L. Carter, and D.M. Lauderdale
Potential exists for reduced water use and improved water quality in container nurseries through redesign of the container to minimize leaching. `Celebrate' poinsettias were grown in trade gallon containers with modified drainage hole number and size. Irrigation was applied when an individual container's medium decreased to 80% of container capacity; a gravimetric method was used to determine daily water requirements. Containers with one drainage hole in the center bottom reduced applied water (13%) and leachate volume (90%) compared to standard nursery containers (4 drainage holes in the side and one in the center bottom). Plant quality was similar with these treatments.
L.M. Beckett, B.K. Behe, C.F. Deneke, and C.H. Gilliam
There are indications that the U.S. herbaceous perennial plant industry has grown substantially in the last decade. Government census data on perennials is sparse, very general, and collected infrequently. The objective of this research was to define characteristics of the herbaceous perennial plant industry. Questionnaires were sent to members of the Perennial Plant Association in 1990. We requested that the person who made decisions on a daily basis, the owner or active manager, respond. Of 439 surveys distributed, 147 were returned for a 33.5% response rate. The average owner or active manager had a high education level (16 years) which was combined with management experience in at least one other company. Firms sold a mean of 30 genera of perennials. Firms selling primarily perennials were younger and more likely to have less total sales than firms selling primarily other plant products. Firms marketing primarily perennials were more likely to sell products by mail and offer a wider selection of genera.
C.K. Crossan, C.H. Gilliam, G.J. Keever, and D.J. Eakes
Herbicide-blended and coated fertilizers were evaluated for prostrate spurge control in containers. Ronstar 2G or Pennant 5G was blended with Nursery Special 12-6-6 fertilizer and Ronstar 50WP or Pennant 7.8E was sprayed on the fertilizer (coated). Ronstar 2G-blended fertilizer and Ronstar. 50WP-coated fertilizer provided weed control at the 4, 8, and 16 lb ai/A rates similiar to broadcast (2G) or sprayed (50WP) herbicide applied at the label rate (4 lb ai/A). Ronstar provided better prostrate spurge weed control than Pennant. Formulation had no affect on weed control when comparing blended or coated fertilizer. Herbicide-blended and coated fertilizers provided effective prostrate spurge contol in containers.
C.K. Palmer, C.H. Gilliam, G.J. Keever, J.W. Olive, and D.J. Eakes
Pampas grass seedlings in 72-cell pack containers were transplanted into containers with a root observation window (17.8 × 10.2 cm) and treated with selected preemergence applied herbicides. Root numbers were counted in the upper and lower 8.9 cm of the viewing window until 16 days after treatment (DAT) when the windows became full of roots. Root growth in both the upper and lower window was suppressed with application of Factor 65 WG and Pendulum 60 WDG at the X and 2X rates at 16 DAT. Ronstar 2G and Pendulum 2G at the recommended rates and nontreated control plants had similar root numbers at 16 DAT. At 16 DAT, the greatest number of club roots formed on plants treated with the dinitroaniline herbicides; Pendulum 2G, Pendulum 60 WDG, and Factor 65 WG. Shoot growth was not affected by treatment.