Nutrient concentration of azalea (Rhododendron sp.), juniper (Juniperus sp.), crapemyrtle (Lagerstroemia indica L.), and camellia (Camellia sp.) did not differ between leaves dried in microwave or conventional ovens.
Rabbiteye blueberry plants (Vaccinium ashei, Reade) which had been planted in 1947 and fertilized with complete fertilizers until 1962 were neglected for 14 years. Because of the vigorous growth, good foliage color, and quality fruit production of these unfertilized plants, soil and leaf nutrient levels were examined 20 and 21 years after the last fertilization. Whereas the soil pH was optimum at 4.5 both years, the soil P was very high in 1982 and medium in 1983. The soil K was medium in 1982 and low in 1983; the soil Ca and Mg were low both years. Soil micronutrients were low and typical for unfertilized Coastal Plain soils. Generally, all leaf nutrient constituents were on the low end of the ranges reported in the literature. Nonetheless the plants continued to grow and produce well, indicating that some old, deep-rooted rabbiteye blueberry plants require less fertilizer than had been thought previously.
Rabbiteye blueberry plants (Vaccinium ashei Reade) are generally vigorous and adaptable to a wide range of soil textures. Reduced growth and yield are associated with high soil pH in most instances. Experiments were conducted to elucidate the relationship between soil pH of a sandy clay loam soil and growth yield of 2 rabbiteye cultivars. Yields of ‘Delite’ and ‘Tifblue’ were decreased with increasing pH from 5.1 to 6.3. ‘Delite’ plants had good observed growth and foliage color at soil pH 5.0 to 5.5. Observed growth appeared to decrease and chlorosis increase with increasing pH up to 6.5 Growth of ‘Tifblue’ differed little among the soil pH treatments, because all plants were slightly to severely chlorotic. Higher yields were obtained from ‘Tifblue’ than from ‘Delite’.
Rickettsia-like bacteria (RLB) are the presumptive cause of phony peach disease and are most numerous in peach (Prunus persica (L.) Batsch) roots. Of apparently healthy peach trees in a heavily infected orchard, 54% had RLB in root samples evaluated by 400 × phase contrast microscopy. Removing all peach trees with visible symptoms of phony peach disease would minimize the number of trees in the orchard infected with RLB. Of trees visibly infected with phony peach disease, 8% had root samples free of RLB on both sampling dates. Leaf concentrations of Mg and B varied significantly (P < 0.7%) with RLB levels in peach roots on 3 of 4 sampling dates. No element tested (P = 5%) separated roots free of RLB on two sampling dates from roots averaging 1 to 9 RLB per microscope field on one date and free of RLB on another date. RLB in peach roots preceded development of visible symptoms of phony peach and changes in leaf elemental concentrations. Soil analysis did not identify RLB infected tree roots (P = 5%).