Two experiments were conducted to evaluate the effects of cyclic irrigation on leachate NO3-N concentration, container leachate volume, total effluent volume, and growth of Ilex crenata Thunb. `Compacta'. In Expt. 1, container leachate volume was reduced 34% when 13 mm of water was applied in three cycles compared to continuous irrigation of 13 mm per unit time. Forty-nine percent less container leachate volume was collected from a continuous application of 8 mm than from that of 13 mm water. In Expt. 2, container leachate volume was reduced 71% when 6 mm was applied in a single application over 30 minutes compared to 13 mm applied continuously for 1 hour. Total effluent was reduced by 14% and 10% in Expts. 1 and 2, respectively, when 13-mm irrigation was applied in three cycles compared to one continuous irrigation. Container leachate NO3-N concentrations from cyclic irrigation were generally less than leachate NO3-N concentrations from continuous irrigation treatments. The percentage of applied N leached as NO3-N ranged from 46% when 13-mm irrigation was applied in three cycles to 63% when 13-mm irrigation was applied in a single cycle. Leachate NO3-N concentration was reduced as irrigation volume was reduced from 13 to 6 mm in Expt. 2. Percentage of applied N leached as NO3-N was 63%, 56%, and 47% when 13-mm irrigation was applied in one, two, and three cycles, respectively, compared to 19%, 16%, and 15% when 6-mm irrigation was applied in one, two, and three cycles, respectively. `Compacta' holly shoot and root growth were minimally affected by cyclic irrigation or irrigation volume.

With environmental concerns increasing, non-chemical weed control in container plant production is increasing in the United States. Pine bark mini-nuggets were evaluated as a non-chemical weed control technique for two weed species; Chamaesyce maculata (L.) Small (spotted spurge) and Eclipta alba (L.) Hassk.(eclipta). On June 19, 2006, seed (25 per container) were directly placed on the potting substrate surface of #3 containers before mulching with pine bark mini-nuggets to a depth of either 0, 1.27 or 2.54 cm (0, 0.5 or 1.0 in). Additional treatments consisted of applying the mini-nugget mulch at either 1.27 or 2.54 cm (0.5 or 1.0 in) on the potting substrate then overseeding with either spotted spurge or eclipta. Eclipta number per container were 87% less 60 days after seeding (DAS) with the 1.0 in mulch depth compared to non-mulched. Furthermore, spotted spurge fresh weight (FW) was reduced by 45 and 87% (0.5 and 1.0 in, respectively) compared to the non-mulched treatment. The experiment was repeated on August 30 and spurge number per container was 90% less 60 DAS in the 1.0 inch mulch treatment compared to the non-treated containers. A third and fourth experiment also demonstrated that pine bark mini-nuggets have potential to provide non-chemical weed control in nursery crops grown in #3 containers. Results, suggest that with proper application pine bark mini-nuggets can enhance weed control in container nurseries.

No abstract

Twenty-four nurseries producing container-grown plants were surveyed along the coastal zone of south Alabama to determine Best Management Practices (BMPs) implemented since 1988. All nurseries utilized multiple BMPs. Seventy-five percent of all nurseries surveyed have the capability to capture runoff water; however, larger nurseries (medium 4.5–16.6 ha (11–40 A); large 16.6+ ha (40+A)) were more likely to capture runoff than smaller nurseries 0.4–4.1 ha (1–10 A). Since 1988, 78% of all collection ponds have been built with 44% of those being built in the past 5 years. Other BMPs widely used included installation of grass filter/erosion strips, having specific personnel devoted to water management, use of control release fertilizers, scouting for pests, use of horticultural oils, and staggered herbicide applications.

Studies were conducted to evaluate recycled waste paper mulch as a means of controlling weeds in the production of container-grown crops. Two forms of recycled waste paper products were evaluated—pelletized and crumbled. Both were tested at two depths, 12.5 mm (0.5 in) and 25 mm (1 in). A fabric disk and a fabric disk treated with Spin Out were also evaluated. With both the recycled waste paper mulch treatments and the fabric disk treatments, spurge seed were sown either under or on top of the treatment. Recycled waste paper pellets applied to a depth of 25 mm (1 in) suppressed spurge germination, regardless of whether spurge seed were sown on top of the mulch or under the mulch. Recycled crumble provided poor spurge control at both depths, and there was increased spurge growth when spurge were sown on top of the mulch compared to when the seed were sown under the crumble mulch. Pellets at the 25 mm (1 in) depth, provided weed control equal to that of Rout (oxyfluorfen + oryzalin) herbicide. Results from the fabric disks showed limited spurge control was obtained with any treatment. Fabric disks allowed weed growth around the container circumference and in the area where the disk fits around the plant. Both cultivars of azaleas grown with recycled waste paper mulch were generally similar in size to non-treated control plants and Rout treated plants at 240 DAT (days after treatment). At 550 DAT plant growth was similar among all treatments except ‘Fashion’ azalea had smaller growth indices when grown with pellets compared to those grown with crumble. Container medium solution pH and electrical conductivity (soluble salts) were within the recommended range for acceptable plant growth. Research suggests that pellets applied at 25 mm (1 in) should provide effective non-chemical weed control resulting in less herbicide use and/or fewer hours of labor for weeding.