Search Results
Abstract
The relationship between water extraction (1:1.5) values and nutrient uptake in geranium (Pelargonium × hortorum Bailey) growing in moss peat (peat), bark, or moss peat and soil media was investigated. Nitrogen, P, and K fertilizers were incorporated in increments in the starting media and applied again in solution, about at the crop midpoint. Desirable nutrient N(NH4 +-N + NO3 --N), P(H2PO4 --P) and K(K+) values (DV) from media analysis at the start of the experiments (MDV) and midway to flowering (FDV) also were calculated from regression equations on the basis of maximum growth rates, maximum dry weight production at midharvest, and final harvest. The relationships between plant uptake of N, P, and K and the water extract concentrations were generally very good, except for K in bark for both harvests and in peat at the first harvest, and an underestimated P uptake in peat + soil and in bark. The media DV obtained using growth data were broadly similar to those using plant dry weight data, although somewhat lower for N during the early growing period.
Pine bark is a widely used substrate component in the southeastern and mid-Atlantic regions of the U.S. nursery industry for the production of container-grown, woody ornamental crops. As a result of the high porosity and relatively low water
temperature interferes with phenology comes from the common orchard practice of painting stems to protect them from disease ( Karels and Boonstra, 2003 ; Sheppard et al., 2016 ). White bark is also naturally displayed in species of Betula , Fraxinus , and
Abstract
The external surfaces and internal structures of particles of milled pine bark (Pinus taeda L. and P. elliottii Engelm.) were examined with scanning electron microscopy. Numerous external openings, cracked cell walls and internal cellular connections, that might allow water penetration were observed. Periderm surfaces were without pores, and contained rough surfaces and apparently waxy substances that might resist water penetration or absorption.
Abstract
The pistachio (Pistacia vera L.), characteristically a biennial bearer, produces its most extensive shoot growth in years of heavy crop production. Whereas levels of total sugars in bark and wood of bearing and nonbearing branches were similar throughout the year, starch levels tended generally to be higher in nonbearing than in bearing branches. Consequently, nonbearing branches one year gave rise to heavy crops the next and, beacuse of greater quantities of reserve foods, also produced extensive shoot growth. Bearing branches of that same year, .however, produced few or no nuts the next and, because of lesser quantities of reserve foods, produced markedly less shoot growth. No relationship between total nitrogen level and shoot growth or fruiting was evident.
Abstract
Pine bark was shown to adsorb 1.5 mg of N/g of bark when NH4 solutions were leached through the bark. Increasing pH of bark increased adsorbed NH4. At pH 3.3, only NH4 was adsorbed to bark particles when a fertilizer solution containing NH4, Ca, K, and Mg was applied. However, adsorption of NH4 and other cations increased as pH was increased from 3.8 to 5.8. These data indicate that 2 types of sites exist for the adsorption of NH4 to pine bark. One site is effective at lower pH; the other is active as pH increases. Daily application of 2.5 cm of water containing 50 ppm NH4 required 20 days for equilibration to occur so as to satisfy all binding sites. Thus, incorporation of NH4 into a pine-bark medium prior to planting may be advisable to prevent low N levels from occurring in the container solution due to NH4 binding when plants are first planted and fertilized.
Abstract
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.
Abstract
In 4 experiments conducted to study internal bark necrosis (IBN) in apple, ‘Delicious’ trees were treated with Mn, Fe, Cu, and Al (100 and 200 ppm in nutrient solution), Mn, Fe, Cu, plus Al (50 ppm each) and a minus B treatment. Only trees receiving Mn and minus B developed IBN symptoms. Trees grown under normal and low levels of Ca and receiving variable concentrations of Mn (0, 25, 50, 75, and 100 ppm) developed IBN in proportion to Mn concentration. Spur-type and standard ‘Delicious’ trees did not differ in IBN severity. Bark samples with IBN symptoms, when analyzed on the electron microprobe x-ray analyzer, had greater Mn and Ca concentrations in necrotic tissue areas than in non-necrotic areas. IBN lesions induced with minus B had a higher Ca concentration in necrotic areas than in healthy tissue
Abstract
Hardwood bark was used in combination with other materials as media for forsythia and juniper plants in containers with various growing procedures, bark sources, and fertility practices. Based on dry wt, the most rapid growth of forsythia was obtained in a bark and fine sand medium; whereas, the least growth was obtained in soil, peat, and perlite. However, pfitzer juniper plants under 2 different fertility regimes grew most rapidly in a bark, soil, and peat medium, slowest in a bark and torpedo #2 sand medium, and at an intermediate growth rate in soil, peat, and perlite. The standard mix (soil, peat, and perlite) was more acidic than the experimental mixes containing bark and sand. Chlorotic plants were more numerous in acidic mixes. Leaf tissue analyses from the plants grown in the peat amended bark and standard mix had higher Fe and Mn concn than plants grown in a bark-sand mix.
Container-grown Viburnum plicatum Thunb. var. tomentosum (Thunb.) Miq. `Mariesii' were planted in unamended planting holes, tilled plots, and tilled plots amended with aged pine bark. A 36-day drought was initiated 108 days after planting. Amending induced N deficiencies, reduced shoot growth, and increased root growth. Plants harvested from tilled and planting-hole plots at drought initiation had 63% and 68% more dry weight, respectively, than plants from amended plots. Between 8 and 19 days after drought (DAD) initiation, plants from tilled plots maintained higher relative leaf water content (RLWC) than plants from planting holes. Plants in amended plots maintained higher RLWC than both other treatments between 7 and 33 DAD. Amended and tilled treatments had higher relative leaf expansion rates (RLERs) than the planting-hole treatment 8, 11, 13, and 15 DAD. As the drought lengthened, plants in amended plots maintained higher RLERs than plants in tilled plots. While plants in pine bark-amended plots were more drought tolerant than those in tilled plots, it is unclear if increased drought tolerance was caused by the improved rooting environment or N deficiency.