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Growing and utilizing sorghums for forage Texto completo
1930
Vinall, H. N. (Harry Nelson) | Getty, R. E. (Robert Ellsworth)
Growing trees for forest planting in Montana and Idaho Texto completo
1930
Olson, D. S. (David Segrid)
Growth and development with special reference to domestic animals | Measurements of growing Holstein and Jersey cattle on Missouri Farms | Prediction charts for growth of cattle
1930
Ragsdale, A. C. (Arthur Chester) | Regan, M. J. | Brody, Samuel
Special price list : a descriptive price list of of uncommon and choice evergreen seedlings, rooted cuttings and transplants suitable for planting out in rows for growing into larger specimens : fall 1930--spring 1931 Texto completo
1930
Profits from farm woods Texto completo
1930
Mattoon, Wilbur R. (Wilbur Reed)
The growing of timber on farm land not suitable or not needed for field crops or pasture is now generally recognized as a profitable farm enterprise. Owners of timberland will be interested in the experiences of farmers who by good methods of cutting, using, and marketing, have made their woodlands profitable.
Mostrar más [+] Menos [-]Relation of oragnic food reserves to the growth of some Kansas pasture plants Texto completo
1930
Aldous, A.E.
These data indicate that perennial herbacious plants decrease in organic reserves up to about the time of flower, after which the plants begin to restore the reserves which must have been drawn on to produce the top growth. From the work done, it appears that the data on organic food reserves will be helpful in determining the growing requirements of pasture plants and in knowing how to maintain or increase the vigor and productivity of desirable species. The information will also be equally valuable in planning the eradication of worthless plants by showing the season when these plants have the least resistance to eradication methods. To make the data more accurate, it would be desirable to have improved methods for obtaining more uniform samples and for making the analyses in order to measure more accurately the differences and quantity of the food reserves.
Mostrar más [+] Menos [-]Lime-magnesia ratios in dolomitic limestones as influencing solution and soil reactions Texto completo
1930
MacIntire, W.H. | Shaw, W.M.
A study was made to determine the influence that calcium-magnesium ratios exert upon the behavior of dolomites toward carbonated water. The higher proportions of calcium the greater were the alkalinities of the extracts and the more quickly were equilibria obtained in initial carbonated water suspensions. The Ca:Mg ratios determined the proportions in which the two elements are initially and progressively available for absorption in the soil system. When subjected to repeated treatments with carbonated water, the dolomites at first disintegrated through the dissolving out of CaCO3 and CaCO3-MgCO3; but after the removal of the CaCO3 excess, the dolomite residues yielded solutions in a constant Ca:Mg ratio of 1:1. Additions of CaCO3 and MgCO3 to dolomite suspensions in carbonated water were found to be reciprocally repressive upon solubility and mutually protective to the solid-phase dolomite. It is pointed out that the Ca:Mg ratio of a solid dolomite, or that of its carbonated-water solution, is not an index to the proportions of calcium and magnesium that are to be found in the soil solution after the dolomite has become a part of the soil system. The addition of economic amounts of dolomite resulted in percolates that contained less calcium and more magnesium than did those from the untreated soil. It was shown that acids engendered in a soil-dolomite medium will combine preferentially with magnesium to enhance the magnesium outgo from fallow soil, or to enrich the contents of growing plants. It was pointed out that dolomites exert a protective action upon the hydrolysis of both native calcium and native potassium, the latter function being in common with that of high-calcic limestone. It was also pointed out that periodic outgo of calcium and magnesium from a dolomite addition differs from that derived from its calcined oxides. The correlation of solubility and acid-reaction studies with lysimeter findings apparently justifies the conclusion that, under humid conditions, additions of dolomitic limestone cannot produce a toxic condition from an accumulation of magnesium per se, since the outgo of added magnesium exceeds that of added calcium.
Mostrar más [+] Menos [-]Effect of soil type and fertilizer treatment on the composition of the soybean plant Texto completo
1930
Austin, R.H.
Fertilizer tests with soybeans were located on five soil types from which crops samples were taken periodically for laboratory studies. The samples were analyzed for total ash, calcium, magnesium, nitrogen, sulfur, phosphorus, and potassium. Tests were conducted in the in the greenhouse to study the effect of soil type and fertilization with phosphorus and potassium upon the phosphorus and contents of the cell sap of the plant. The total ash content of the soybean plants was lowest 110 days after seeding, and in many cases it was highest 73 days after seeding. In the young plants the high ash content was associated with smaller growth. The calcium, magnesium, and nitrogen contents of the soybean plant decreased with the age of the plants. There was very little change in the sulfur content during growth or due to the influence of fertilizers or soil type differences. The results of these experiments suggest a tendency for the phosphorus content of the soybean plants to increase during the latter half of the growing period. The potassium content was very irregular, but the variations were small. The effects of fertilizer treatments upon the composition of the plant were small. Fertilizers were more effective in changing the composition of the soybean plants grown on Coloma sand and least effective on Miami loam. Plants on Brookston clay loam had the highest magnesium content (1.08%), one of the highest nitrogen (4.81%) and one of the lowest calcium (2.16%) and ash (9.72%) contents 35 days after seeding, among the plants without fertilizer treatment. Plants on Hillsdale sandy loam and on Coloma sand had the highest ash (10.70%) and 10.12%) and calcium (2.70% and 2.79%) contents and the lowest magnesium (0.58% and 0.69%) and nitrogen (4.41% and 4.17%) contents of the unfertilized plants 35 days after seedings. The phosphorus content of the unfertilized soybean plants varied from 0.46% in the plants on Brookston clay loam to 0.23% in the plants on Hillsdale sandy loam. The Brookston clay loam produced plants that had the lowest calcium (1.79%) the highest magnesium (1.08%) and one of the highest ash (10.61%) and nitrogen (3.46%) contents of the unfertilized soybeans 73 days after seeding. For unfertilized soybeans 110 days after seeding, the plants on Brookston clay loam had the highest ash (8.56%) and magnesium (0.79%) contents, the plants on Coloma sand the highest calcium (2.11%) and phosphorus (0.46%) contents, and the plants on Kewanee loam the highest nitrogen (3.52%), content. Plants on Miami loam contained the lowest ash (6.29%), calcium (1.29%), sulfur (0.22%), phosphorus (0.28%), and potassium (0.53%) contents and one of the highest nitrogen (3.27%) contents of the plants grown on the unfertilized plats 110 days after seeding. All treatments on Fox sandy loam increased the nitrogen content of the plants. The phosphorus and potassium contents of the cell sap of soybean plants were increased by applications of phosphorus and potassium. The phosphorus, potassium, and calcium contents of the cell sap were affected by the type of soil upon which the plants grew. The soil type upon which the soybeans grew was a greater factor in determining the composition of the plants than was the application of moderate amounts of fertilizers.
Mostrar más [+] Menos [-]Controlling perennial weeds with chlorates Texto completo
1930
Hulbert, H.W. | Remsberg, J.D. | Spence, H.L.
The commercial use of chlorates for weed control purposes in Idaho has met with gratifying success. There are certain features which limit the effectiveness of the treatments. These may be summarized in a general way from extensive observations made during the entire growing season. It has become very apparent that the full effectiveness of the treatments is not evident until the following season. It is not uncommon for the plants to continue to grow after the applications, only to disappear entirely after the winter season. In order that best results be obtained, the areas should not be cultivated just prior to the application of chlorates. The under-ground root system should be represented by an appropriate amount of top growth. The effectiveness of the treatments increases as the plant approaches maturity. This possibly may be attributed to the fibrous nature of the plant nearing maturity and the ease of dissemination of the chemical through the root system. The borders of the treated areas should be watched closely the following season, since it is apparent that the underground root system extends beyond the outer limit of the top growth. Areas should not be irrigated following treatment. This apparently results in dissemination of the chemical through the soil moisture and subsequent leaching from the soil. In instances where the water table approaches the surface of the ground at certain seasons of the year, it has been noted that treatments are more effective if the water table remains stationary at the time of application or is slowly lowering. In case the water table is continually approaching the surface of the ground, there is a zone of roots near that water table which will not be effectively killed. The temperature of the air and the time of the day during which the application is made appear to have very little influence upon the effectiveness. Complete eradication does not follow with sufficient frequency to warrant the statement that a single application is sufficient. Experience has shown that it is much better to inform the farmer that he should not expect complete control with a single application and have him pleased if no further work is necessary, than it is to inform him that complete control may be expected and have him disappointed if further work is required. Under irrigation, it would seem that the following general recommendations might be made: Dissolve the chemical in water at the rate of 1 pound per gallon. Apply to plants in undisturbed areas after full bloom stage and in sufficient quantity to moisten all vegetation. Leave the area undisturbed through the remainder of the season, except in the case of white top where a second application may be required to prevent seeding. Repeat the application the following season, if necessary. In non-irrigated areas, the general recommendation for all perennial weeds is to apply a 10% solution in sufficient amount to wet the weeds thoroughly.
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