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Two to four crops were grown in sequence in three series of pots on two soils, Charlottetown fine sandy loam (Chfsl) and Queens sandy clay loam (Qscl). The rates of applied S to the soils were: 0, 50, 100, and 150 ppm. None of the crops grown in the first sequence responded to S, but crops grown in later sequences responded to S in varying degrees. Sulfur applications resulted in about 2‐ to 4‐fold increases in the yield of rutabaga roots (Brassica napobrassica, Mill. cv. ‘York’). The plants deficient in S had thin roots and the leaves were reddish‐yellow with scorched edges. The kernel and straw yields of barley (Hordeum distichonL., cv. ‘Volla’) and wheat (Triticum aestivumL., cv. ‘Opal’) increased substantially with the addition of S. The S‐deficient plants of barley and wheat were lighter in color with thin stems. Alfalfa (Medicago sativaL., cv. ‘Saranac’) responded to S, with increases of much greater magnitude in the second and third cuts than those in the first cut. The S‐deficiency symptoms, noted as stunting and general yellowing of the entire plants, were mostly confined to the second and third cuts. Four‐ to five‐fold increases in cauliflower (Brassica oleraceabotrytis L., cv. ‘Snowball’) yield with S3and S4treatments were obtained on Qscl, while on the Chfsl the yields decreased at S3and S4levels of S. The yield decreases on the Chfsl were caused by a severe Mo deficiency. Sulfur‐deficient cauliflower plants were stunted with general yellowing of leaf edges. The available soil SO4‐S levels of 2.0 and 2.4 ppm for alfalfa third cut and barley were in the deficiency range. The deficiency levels for wheat and cauliflower would likely be below 2.8 and 4.0 ppm, respectively.

In field experiments, 4.48 kg B/ha added to the soil decreased the grain yield of barley (Hordeum distichonL.) and wheat (Triticum aestivumL.). Under greenhouse conditions, 0.5 ppm, added B reduced wheat yields while 1.0 ppm added B reduced barley yields. The B toxicity in wheat in 1974 and barley and wheat in 1975 at 2.24 kg B/ha as associated with reduced yield was alleviated somewhat by the additions of N to the soil in field experiments, but the effect was not significant. Under greenhouse conditions, addition of 50 ppm N or more reduced B uptake and alleviated B toxicity. In general, the B toxicity symptoms on the foliage under field conditions were associated with >11 ppm B in wheat boot stage tissue (BST) and >14 ppm B in BST of barley. Added B increased the N concentration of grain where yields were decreased due to B toxicity. Wheat yields increased with increased rates of N application in all field experiments, while barley yields increased with increased rates of N in 2 of the 3 years. In field experiments the highest B value was 34 ppm. Concentrations as high as 312 ppm B were found in greenhouse experiments. In the presence of added B under greenhouse conditions, the barley tissue B concentration was much lower when the moisture level near the fertilizer band was low than when it was high.

Total and hot‐water soluble B content of soils ranged from 45 to 124 and 0.38 to 4.67 ppm, respectively. The largest quantities of hot‐water soluble B were recorded in Acadia silty clay loam, Caribou silt loam, and Interval loam to silt loam soil series. Water‐soluble B was comparatively low in soils derived from Permo‐carboniferous rocks. In general the B content was lowest in coarse‐ and highest in fine‐textured soils. Percent of total B in the hot‐water soluble form varied from 0.44 to 4.69, with the highest percentage occurring in the fine‐textured soils and lowest in the coarse‐textured soils. Hot‐water soluble B content was higher in “well‐managed” soils than in “neglected” soils. The quantities of such B were positively correlated (significant at p= 0.01) with organic matter and with total B. Higher amounts of B were fixed by soils after incubation periods of 8 and 12 weeks than after 2 and 4 weeks. A higher percentage of B was fixed in the O'Leary sandy clay loam than in the Dunstaffnage sandy loam soil with all incubation periods. Varying the moisture content of soil from 50 to 100% of the field capacity did not affect the B fixed over a 12‐week period.

The suitability of the Ca(OAc)2and Ba(OH)2methods for the determination of COOH groups and of “Total Acidity” [sum of COOH + acidic (phenolic) OH] in soil organic matter preparations was evaluated. In addition, COOH groups and “Total Acidity” were also determined by decarboxylation and discontinuous titrations, respectively. These methods were used for the analysis of functional groups in three different humic and three fulvic acids and in 10 known organic compounds, representing types of structures that might occur in humic and fulvic acids. The Ca(OAc)2method was found to be suitable for the analysis of COOH groups in most of the known compounds and in the soil organic matter preparations investigated. The Ba(OH)2method was found to react with acidic hydrogens in both aliphatic and aromatic compounds and was not specific for phenolic OH groups. However, on the basis of available experimental evidence it is believed that the Ba(OH)2method measures phenolic OH groups in soil organic matter. Both the Ca(OAc)2and Ba(OH)2methods are simple and require neither elaborate equipment nor special skills. They appear to be suitable for use in the routine analysis of purified organic matter.

Organic matter extracted from the O and B2 horizons of a Gray Wooded soil was characterized by ultimate and functional group analyses and by infrared spectroscopy. The analytical data were compared with those obtained by the use of the same methods on Podzol O and Bh organic matter. The experimental data indicated that Gray Wooded humic and fulvic acids were chemically similar to Podzol humic and fulvic acids except that Gray Wooded organic matter contained more phenolic hydroxyl groups. In analogy with Podzols, approximately 70% of the organic matter extracted from the Gray Wooded O horizon was humic acid, while 90% of the extract from the B2 horizon consisted of fulvic acid. Gray Wooded organic matter was difficult to extract and purify because of intimate association with clay and possibly other inorganic constituents.

A greenhouse study involving four levels of lime and six levels of B, and a field study at two locations involving three levels of lime and five levels of B were conducted on rutabaga (Brassica napobrassica, Mill. var. ‘York’). Brown‐heart was more severe at high pH than at low pH under B deficiency conditions. The effect of lime on the appearance of B deficiency symptoms was a physiological effect in the plant rather than a chemical reaction in the soil. However, lime applications, generally decreased the B concentrations of leaf tissue. Calcium/B ratios in the leaf tissue were inversely related to the hot‐water‐soluble B content of the soil. Under field conditions, liming increased the Ca/B ratio of leaf tissue in most cases. Calcium/B ratios of 3,300 to 8,500 and B concentrations of 2 to 7 ppm in leaf tissue were associated with very severe brown‐heart condition. Leaf tissue Ca/B ratios of less than 400 and B concentrations greater than 40 ppm, when the roots began to enlarge were associated with roots free from brown‐heart.

A greenhouse study involving four levels each of Mo and limestone indicated that without application of both Mo and lime, the cauliflower (Brassica oleracea, var. botrytisL.) crop produced very poor yields on the three soils investigated. Alfalfa (Medicago sativaL., var. ‘Narragansett’) was also a failure without added lime. At soil pH values of 5.5 and above, Mo applications increased the yield of alfalfa on Culloden sandy loam and O'Leary sandy clay loam soils, but gave no response on Acadia silty clay loam soil. Bromegrass (Bromus inermisLeyss., var. ‘Saratoga’) showed a marked response to application of lime, but very little response to application of Mo. Cauliflower yield showed a highly significant Mo × lime interaction on Culloden and O'Leary soils, where without added Mo, lime treatment up to pH 6.5 failed to show any increase in yield. Addition of different levels of lime did not change the exchangeable Mo content of any of the three soils, after growing crops. The application of Mo or lime increased the Mo content of all crop tissues up to the highest level of applied Mo or lime. Application of lime substantially increased the Mo content of cauliflower and alfalfa while bromegrass showed less increase. There was a marked Mo × lime interaction on the Mo content of all crops, with much higher Mo contents in the plant when lime and Mo were applied together than when either treatment was applied alone. Liming to pH 6.5 without added Mo did not increase the Mo content of crops over 1.5 ppm. In the absence of added Mo, cupping and drying of the edges of true leaves of cauliflower appeared at the early stage of growth whether or not lime had been applied to the soils. During the later stages of growth, these symptoms in most cases were associated with yellowing between the veins of leaves.