N and P fertilizers were applied at increasing rates in alternating directions crossed over (IRADCO) at right angles upon each other. One fertilizer was applied so that, in the contiguous strips, the rates increased in alternate directions. The second fertilizer was applied similarly but at right angles to and on top of the first fertilizer. This arrangement with the increasing-rate spreader available allowed 162 combinations of the two fertilizer elements in duplicate in each block. Two such blocks set at right angles to each other were considered to offer reasonable control of possible fertility gradients in the field. The main value of the design is that many fertilizer levels for the establishment of yield response surface functions can be acquired with less effort and in a fraction of the area required with plots of conventional size. The form of the yield response to fertilizer was adequately represented by regression models fitted to the data. The IRADCO design, involving both the field technique and regression modelling, can be used to determine the response to fertilizer levels by various crops at several locations.

Reddish brown and associated horizons from several buried soils were analyzed for dithionite-, oxalate-, and pyrophosphate-extractable Fe and Al. Although these methods can be used with surficial soils, they are not necessarily applicable to buried soils. However, on the basis of morphology and the fact that dithionite- and oxalate-extractable Fe and Al were always highest for the reddish brown horizon in each profile sequence, it was concluded that these horizons were zones of pedogenic accumulation. Since pyrophosphate-extractable Fe and Al essentially measures only the organic forms of pedogenic Fe and Al, and organic compounds are usually subjected to further degradation after burial, it is suggested that for buried soils dithionite- and oxalate-extractable Fe and Al are more meaningful. Comparisons with data in the literature, giving typical ranges for the main types of soil horizons, allowed both the classification of the profiles sampled and the recognition of past processes, such as gleying, which are not identifiable morphologically today.

Seven species of grass were grown on plots to which N had been applied at progressively increasing rates (0 to 775 kg N/ha) to reach and exceed those required for maximum yields. Yield of hay and protein in all seven grasses increased with N fertilizer. Recoveries of N were only 12 to 31% when applied once, and 8 to 14% when applied every year. Because these recoveries are considered to be uneconomical, massive rates of N fertilizer are not recommended. Intermediate wheatgrass produced the most hay and protein. All seven grasses responded most to applied N in the first 2 years after application, regardless of age of stand. Cultivated grasses are assuming greater importance in the dryland culture of the semiarid plains. Grasses are being grown for short-term use in rotation with grains to improve structure and to allow a buildup of organic matter and N in the soil. Also, cattle are being finished with less gr4in; thus greater quantities of perennial hay as well as permanent pasture are required. In these situations, N fertilizer would be expected to enhance yield and protein content. Many studies concerning the response of grasses to N fertilizer have been restricted to a single species (Lorenz and Rogler 1962; Mason and Miltimore 1972; Sneva 1973). However, Heinricks and Clark (1961) found that five species of grass all responded to N fertilizer although they differed in their efficiencies of N use. Old stands of crested wheatgrass (CWG) increased production with N fertilizer if soil moisture was adequate during the growing season (Seamands and Lang 1960). Kilcher (1958) found that N fertilization of CWG was economical in most years. For Russian wildrye (RWR), fertilization was economical only in the first 2 moist years and, for intermediate wheatgrass (IWG), it was economical in only the first wet year. Smika et al. (1960) reported that bromegrass, CWG, and RWR were inefficient users of fertilizer N and that recovery of N increased in cooler years. The objective of this study was to determine those grass species that would respond most efficiently to applications of high rates of N fertilizer. Materials and Methods The soil of the experimental site at the Agriculture Canada Research Station, Lethbridge, Alta., was a Lethbridge loam (Typic Haploboroll, Orthic Dark Brown Chemozemic soil developed on alluviallacustrine parent material) previously cropped in a grain-fallow rotation. Before the study was started, triple superphosphate (045-0 at 67 kg P/ha) was broadcast uniformly over the experimental area. A Authors are soil scientist and agronomist (retired), respectively, Research Station, Agriculture Canada, Lethbridge, Alberta, TIJ 4Bl. Manuscript received August 31, 1978. randomized block design with four replicates was used. Each plot consisted of 12 rows of a single species seeded in rows 20 cm apart and 40 m long in the spring of 1965. Seven grasses were seeded: intermediate wheatgrass (IWG, Agropyron intermedium (Host) Beauv.); Russian wildrye (RWR, Elymus junceus Fisch.); streambank wheatgrass (SWG, A. riparium Scribn. and Smith); crested wheatgrass (CWG, A. cristatum (L.) Gaertn. cv Fairway); timothy (TIM, Phleum pratense L. cv Climax); western wheatgrass (WWG, A. smithii Rydb.); and bromegrass (BRG, Bromus inermis Leyss.). Unless otherwise stated, the crops seeded were commercial grade. In early spring of each of 3 consecutive years, single applications of ammonium nitrate (34-0-0) were broadcast on the appropriate blocks as a means of evaluating the effect of age of stand. The fertilizer was applied once with an increasing-rate spreader (Lutwick et al. 1965) along each grass plot at rates from 0 to 775 kg N/ha. Plots 1 to 28 were fertilized in 1966, 29 to 56 in 1967, and 57 to 84 in 1968. As an adjunct to the experiment, plots 85 to 1 12 were fertilized at the same rates of N in 1967, 1968, 1969, and 1970 to allow evaluation of the effect of applying fertilizer every year. Yield measurements were taken each year from 1966 to 1970, except that some plots of TIM were not harvested in 1970 because of excessive weed growth. All forages were harvested when CWG reached the seed-set stage. The center four rows of each 40-m strip were cut for yield beginning at 2 m and then at every 4 m along the strip. Each of these points was the center of an 80-cm length and they were located where the rates of N application were 0, 28, 76, 165, 254, 354, 465, 572, 671, and 744 kg N/ha. The harvested area was 80 cm x 80 cm. The forage samples were dried in a forced-draft oven at 60?C. Samples collected at 0, 165, 465, and 744 kg N/ha rates were analyzed for total N (protein) content by the Kjeldahl-Wilfarth-Gunning method (Association of Official Agricultural Chemists 1950) after grinding in a Wiley mill to pass a 1-mm sieve. All yield and N content.data, within species and year of harvest, were fitted to regression curves of the form y = a + bX + cX/ where y is the estimated yield (kg/ha) or estimated N content (%) and X is the fertilizer rate (kg/ha). There were 111 equations for yield and 111 for total N content. Of these, only 21 correlation coefficients were not significant (P<0.05) and they occurred mainly in the fourth and fifth years after fertilizing. N content data are not reported but were used to calculate N uptake (yield x N content). Comparisons were made with derived data; thus, intercepts were taken as yield without N fertilizer (No) and the first derivative of the equation allowed calculation of the rate of N applied at maximum yield (Nm). Yields and N uptake for the successive years at Nm and No in the year of application are reported. With these data, the species should show their relative and maximum capabilities for growth under the climatic conditions that occurred at the experimental site. Meteorological data were collected about 1 .5 km from the plot area. Comparatively, 1966 and 1967 were the wettest years and 1968 and 1970 were the driest, based on the moisture deficit calculated as the difference between evaporation and precipitation for May and June (Table 1). Also, weather in 1967 was relatively cool especially in April, when high precipitation was received. JOU RNAL OF RANGE MANAGEMENT 32(6), November 1979 433 This content downloaded from 157.55.39.45 on Wed, 05 Oct 2016 04:10:28 UTC All use subject to http://about.jstor.org/terms Table 1. Weather data collected about 1.5 km from plot site. Seasonal mean or Year April May June July total* Mean temperature (?C) 1965 5.3 10.1 13.8 18.5 11.93 1966 3.7 11.4 14.1 17.2 11.6

The effects of four rates of N and P fertilizers applied in the spring to alfalfa and crested wheatgrass, grown singly and in mixture, at three ages of stand were investigated. N fertilizer increased yields and protein content of the grass in the year of application regardless of age of stand; the effect in subsequent years depended upon the level of yield in the year of application. The results indicated that grass should be fertilized with N every year at a rate related to the amounts of N removed from the soil in the preceding year. N fertilizer also increased the yield of the mixture in the year of application. The proportion of alfalfa in the hay mixture decreased with age and with applications of N fertilizer. This effect of N fertilizer was brought about by changes in the absolute yield of the grass component but not that of the alfalfa component of the mixture. The management of the mixture is affected by management of the grass component and any increases in yield and quality of the grass are at the expense of the alfalfa. P fertilizer slightly increased the P content of all forages, regardless of age of stand, both in the year of application and in the succeeding years, but did not increase yields.

Clay–organic complexes, humic substances, and grass roots were separated from the Ah horizons of soils sampled at undisturbed sites in three Chernozemic soil zones from under dominantly single species of grass. Derivative thermograms (DTG) and infrared (IR) absorption spectra of the soil materials and of the lignins of the grass roots were compared. The data indicated that the organic matter (OM) of the Black soils contained fewer aliphatic groups and more carboxyl groups and was more resistant to thermal decomposition than that of the Brown soils; the OM of the Dark Brown soils was intermediate. The root lignins from the same soils showed many of the same zonal variations in the IR and DTG properties as did the soil OM.

Total-N and NO3-N content of forage were determined for six grass species — timothy (Phleum pratense L.); crested wheatgrass (Agropyron cristatum (L.) Gaertn.); intermediate wheatgrass (Agropyron intermedium (Host) Beauv.); stream-bank wheatgrass (Agropyron riparium Scribn. and Smith); bromegrass (Bromus inermis Leyss.); and Russian wild ryegrass (Elymus junceus Fisch.). The grasses were fertilized with ammonium nitrate in early spring and were sampled at four levels of applied N — 0, 185, 550, and 940 kg/ha — and at three stages of maturity — early heading, anthesis, and seed-set. Total-N and NO3-N increased in all grasses with increasing levels of N fertilizer; Russian wild ryegrass showed the greatest increase and timothy the least. As maturity advanced, total-N content decreased. Total-N contents were similar in crested wheatgrass, intermediate wheatgrass, and streambank wheatgrass. As maturity advanced, the NO3-N content of fertilized timothy, crested wheatgrass, and bromegrass decreased while that of Russian wild ryegrass increased. The NO3-N content of intermediate wheatgrass and of stream-bank wheatgrass was highest at anthesis. At 0 and 185 kg N/ha, the NO3-N content was well below the lethal level for ruminants, but at the two higher N fertilizer levels it often exceeded the lethal level. Timothy can be considered a low, Russian wild ryegrass a very high, and the other four grasses high, NO3-N accumulators.

Vertical sections of paleosols along the Upper North Saskatchewan River valley show horizons that have distinct brown to reddish-brown colors. Based on such criteria as time for water droplet penetration, magnetic susceptibility, and crystallization of Fe oxides, together with present conditions and vegetation of the fans and floodplain in that area, it was concluded that these brown horizons were fire-affected. The organic debris in the bogs before a fire is continually being enriched with silt blowing from the floodplain. The colored horizons are considered to be a combination of accessed eolian matter reddened in the layer of burning debris and some mineral matter reddened by conducted heat.

Six grass species were grown at four levels of N fertilizer and harvested at three stages of maturity. Two methods were used to estimate the protein content of the grasses: the Orange G dye-binding capacity and total N content. Values from the two methods were correlated to show the relationships between the two methods when species, levels of N fertilizer, and stages of maturity varied. The correlations between Orange G dye-binding capacity and total N were linear, positive, and highly significant. The variation about the regression lines was greatest when total N content was greater than 2.5% of plant dry weight; this condition was especially marked at early heading stage and high rates of N fertilizer. The precise relationships also varied among species. The Orange G dye-binding method for determining protein content is satisfactory for grasses where the total N content of the grass does not exceed 2.5%, but is not satisfactory for grasses with higher total N contents.

Three pairs of soil profiles developed on calcareous parent materials and two pairs of soil profiles developed on acidic parent materials were chosen morphologically in the field to represent Brunisolic/Luvisolic and Brunisolic/Podzolic features, respectively. Oxalate-, pyrophosphate-, and dithionite-extractable Fe were determined for each horizon. Also, Fe was partitioned into crystalline, "aged" and "gel" amorphous hydrous oxides, and organic forms. Humic acids extracted from each horizon with alkali were characterized by infrared absorption spectroscopy. Soils developed on acidic parent materials contained more extractable Fe than did those developed on calcareous parent materials. Only one horizon fitted the requirements of the chemical definition of a Bf horizon. All three reagents indicated zones of depletion and accumulation of Fe in soils developed on calcareous parent materials; oxalate and pyrophosphate did but dithionite did not show these relationships for soils developed on acidic parent materials. With exceptions, extractable Fe was correlated with clay content on the soils with calcareous parent material but was correlated with organic carbon on the soils with acidic parent materials. Well-crystallized Fe showed horizon differentiation in soils with calcareous parent materials and is therefore a weathering product. In soils with acidic parent materials, crystallized Fe was the source of weathering product forms of Fe. Humic acids of soils with acidic parent materials were more highly oxidized and hence more capable of reacting with Fe than were those of soils with calcareous parent materials.

Clay–organic matter complexes (< 2 μ) were separated in four serial extracts through ultrasonic dispersion from a Black Chernozemic soil developed on calcareous till. Derivative thermograms (DTG) of the complexes were similar to those of organic matter extracted from the same soil with alkali. The thermograms of the easily extracted materials (first two extracts) did not have a high temperature peak unless the materials were treated with acid. The thermograms of the difficult to extract materials and of the coarser residual materials (silts and roots) did have a high temperature peak.

Palaeosols may: be found in almost every stream valley in southern Alberta. Humic acids from Ah horizons of palaeosols from five locations were examined by infrared spectroscopy, and the percentage of opal phytoliths in the coarse silt (20 to 50 μ) fraction was determined.The combination of the character of the infrared spectra of humic acids and opal phytolith counts was helpful in explaining the genesis of the palaeosols of the five locations. Sometimes the presence or absence of evidence of human occupation will add to the interpretation. In the locations examined, grasslands apparently have been dominant during post-glacial times with invasions of trees, such as Populus spp. and Salix spp., in the moister and more sheltered riparian habitats in this area. Any of these invasions naturally led to a transformation of these grassland soils.

Soils with very thick Ah horizons occur in downslope positions in the foothills of Alberta. The distribution and type of grass opal phytoliths in these soils and in the surface horizons of associated soils in upslope positions were studied. Opal phytoliths from Calamagrostis species, which grow in moist sites, occur throughout the depth of the cumulic soils. Also, the numbers of opals in the soil increase toward the surface. Since Festuca-type opals occur in only the upslope soil, we conclude that the cumulic soils accrete by soil creep as a result of their downslope position on a valley side.

Nitrogen and phosphorus fertilizers were applied to range vegetation at five locations at rates ranging from 475 to 705 kg/ha N with or without from 380 to 545 kg/ha P. The addition of fertilizers increased average water-use efficiency at all locations. Average magnitude of the increase in relation to unfertilized controls was: control, 33.3 kg/ha dry matter produced per cm of water; P, 37.0 kg/ha/cm; N, 52.3 kg/ha/cm; and, N+P, 73.4 kg/ha/cm. Fall soil moisture had the greatest influence on yield of control and P-treated range vegetation, whereas June precipitation had the greatest influence on yield of N- and N+P-treated range vegetation.

Samples of rough fescue, Festuca scabrella Torr., collected at five stages of growth from areas fertilized at various rates with nitrogen and phosphorus, were analyzed for crude protein, phosphorus, and cellulose; digestibility of cellulose was determined in vitro and the Nutritive Value Index (NVI) was calculated. Fertilization increased the percentage protein and phosphorus, the digestibility of cellulose, and the NVI, but decreased the percentage cellulose. In general, the increases or decreases depended upon the amount of fertilizer applied.

In 1962 and 1963, nitrogen and phosphorus fertilizers were applied at various rates to native fescue range and to range seeded to bromegrass and creeping red fescue. Effect of fertilizers was studied 1, 2, and 3 years after application. Seeded range vegetation responded better than native range vegetation to all levels of fertilizer application. Unfertilized seeded range yielded only one-third as much as unfertilized native range but, at medium to high rates of N or N + P, seeded range yielded from 2 to [Formula: see text] times as much as native range.

Fescue grassland vegetation at three locations in southwestern Alberta was fertilized with P, N, and N + P at various rates. Rates of application by an increasing-rate fertilizer spreader were from 0 to 1,120 kg N/ha and from 0 to 860 kg P/ha. Festuca scabrella Torr. responded to high rates of fertilizer whereas Danthonia parryi Scribn. did not respond. Yields were averaged across locations to show effects of fertilizers 1, 2, 3, and 4 years after application. Yield response curves showed that a residual effect persisted throughout the 4-year study period. Total yield was increased. Value of additional grazing compared with costs of purchase and application of fertilizer showed that fertilization of rangelands in the areas studied was not economically feasible.

The purpose of the study was to examine the surficial deposits , soils and vegetation of a small valley of the Saskatchewan River headwaters in order to establish how an unknown landscape might be subdivided into com­ ponent units of land and vegetation (ecosystem-types) that would be of value to watershed research and management . Surficial deposits were examined and mapped in the whole valley; soils and vegetation studies on a transect representative of the higher areas . Examination of surf icial deposits showed them to be mostly of glaCial origin , though colluvium and alluvium were also present. The most important distinction found was between calcareous and non-calcareous de­ posits , the former being resistant , and the latter more susceptible , to erosion when subj ected to disturbance activities . There were gradations between carbonate-rich and carbonate-poor materials . Soils showed a close aff inity with the types of surficial de­ posits examined , being Grey Wooded and Brown Wooded on calcareous materials , Podz olic and Acid Brown Wooded on non-calcareous materials . The main distinction in the vegetation was the effect of s lope position and groundwater seepage . These condit ions were associated with an assemblage of moistureloving lesser vegetation species and also with gleyed soils . After a complete description of surficial deposits , soils and vegetation , a simple , broad class if ication of the landscape into ecosystem­ types is presented .

Mixed Prairie vegetation in fair condition was fertilized with various rates of P, N, and NP. Rates of application by an increasing-rate spreader were: low, 10–185 kg/ha N, 10–155 kg/ha P; medium, 375–705 kg/ha N, 300–550 kg/ha P; and high, 870–1095 kg/ha N, and 680–820 kg/ha P. Total yield increased as a result of all fertilizer treatments. Palatability of fertilized vegetation was increased. Character of vegetation, unchanged by low rates, was changed by medium and high rates of N and NP. Bouteloua gracilis (HBK.) Lag., Stipa comata Trin. and Rupr., Koeleria cristata (L.) Pers., and Selaginella densa Rydb. decreased; Agropyron smithii Rydb., A. dasystachyum (Hook.) Scribn., and Artemisia frigida Willd. increased; and fertilized plots were invaded by Descurainia sophia (L.) Webb, Chenopodium leptophyllum Nutt., and Hordeum jubatum L. Fertilizer application increased rangeland production by about 300% at low rates and about 900% at high rates; the latter were accompanied by major vegetation changes. Since long-term effects of vegetation changes are unknown, only low rates of fertilizer application, which had little effect on the vegetation, can be recommended.

An area of native prairie containing 80% Festuca scabrella Torr., was fertilized with nitrogen and phosphorus at increasing rates. Samples were collected at the heading stage, one and two years after the fertilizer was applied. A significant inverse correlation (r = 0.68**) existed between percent protein and percent silica in the forage. This and other data indicated that a protein content of 16% would be required to prevent the formation of uroliths in cattle. Phosphorus in the forage was adequate for beef cattle nutrition when phosphorus was applied at 200 kg or more per hectare. The percentage of cellulose was significantly (P <.01) less in the forage from plots fertilized in 1962 than in the forage from plots fertilized in 1961 (residual effect). The percentage of cellulose also decreased significantly (P <.01) with increasing rates of fertilization. Percentage of digestible cellulose and nutritive value index (N.V.I.) were not affected by level or year of fertilization.