Field studies were conducted for 4 years on putting green turf to determine the influence of cultivation practices on the transition from overseeded perennial ryegrass (Lolium perenne L. ‘Yorktown II’) turf to hybrid burmudagrass [Cynodon dactylon (L.)Pers. × C. transvaalensis Burtt-Davies] in the spring. The cultivation practices of core aeration, vertical mowing, and topdressing were shown to have no positive influence of increasing the rate of bermudagrass coverage during the spring on bermudagrass greens overseeded with perennial ryegrass. The verticut treatment resulted in decreased bermudagrass coverage as well as a reduction in turf quality. All cultivation practices resulted in some quality loss at various times during the spring transition period compared to the control.

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Extensive losses in N applied to container-grown woody ornamental plants prompted this investigation to determine a) leaching of N from urea (U) and isobutylidene diurea (IBDU); b) influence of nitrapyrin (NI), a nitrification inhibitor, on N leaching losses from U; and c) to evaluate influences of these materials on growth, quality, and N uptake by Rhododendron obtusum Lindl. cv. Hinodegiri. In root medium composed of 60 pine bark : 30 sand : 10 soil (by volume), 48.8% of applied N from U was leached after 87 days, whereas leachate losses of N from IBDU and U + NI were 42.3% and 37.2%, respectively. All plants attained marketable quality by the end of the study. Azaleas fertilized with IBDU were of significantly higher quality on days 70 and 77 than those treated with U + NI and higher quality on days 77, 84, and 87 than those treated with U. No differences were found in shoot dry weight or N content in shoot tissues.

Coal cinders with pine bark were evaluated as containerized plant growing medium. Rhododendron obtusum Lindl. ‘Hinodegiri’ liners were grown in several combinations of media composed of pine bark mixed with an aged and a recently combusted source of cinders. Measurements of media pH, soluble salts, NO3− –N, NH4+ –N, and 19 extractable nutrient and metallic ions were obtained. Leaf tissue samples were analyzed for 19 elements. Top dry weight, visual growth and chlorosis ratings, and root visual ratings constituted the plant growth parameters measured. Satisfactory growth was generated in pine bark amended with up to 50% cinders from either source.

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