Showing papers in "Journal of Range Management in 1949"

Condition and Management of Range Land Based on Quantitative Ecology.

Abstract: T ODAY there are many different bases for range condition classifications. Stockmen commonly associate the term “range condition” with favorableness of the season. In this sense, good range condition may mean simply that an area recently received good rains. However, professional range conservationists have long associated good range condition with something less fleeting than good seasonal growth. In the glossary of technical terms published by the Society of American Foresters (11)) range condition is defined as “The state of health or productivity of both soil and forage of a given range, in terms of what it could or should be under normal climate and best practicable management”. This article describes a system for determining range condition which considers climate, soil, and vegetation both present and potential. It includes a review of researches that provide a scientific foundation for the system, and shows how earlier qualitative applications have been replaced by quantitative ones. An actual example is used to demonstrate practical application of the system to range management.

Merriam Kangaroo Rat a Factor in Mesquite Propagation on Southern Arizona Range Lands.

Abstract: M ESQUITES (Prosopis spp.), shrubs or trees of little forage value, now occupy nearly 60 million acres of range land in Arizona, New Mexico, and Texas. A large part of this occupation is comparatively recent invasion which has resulted in progressively poorer ranges for domestic livestock grazing, because of accelerated erosion and decreased grass density (Fig. 1). Certain evidence collected on the Santa Rita Experimental Range indicates that the Merriam kangaroo rat (Dipodomys merriami merriami Mearns) is one of the important factors in the spread of this undesirable plant. This study is a part of investigations being conducted by the Southwestern Forest! and Range Experiment Station in cooperation with the University of Arizona Agricultural Experiment Station under RMA Project RM :b-4 for “Research on the basic ecology and physiology in control of undesirable range shrubs.” Identification of the rodents was made by H. G. Reynolds and confirmed by comparison with verified study skins in collection of Dr. C. T. Vorhies, Economic Zoologist, University of Arizona, Tucson, Arizona. The Santa Rita Experimental Range is located in southern Arizona about 30 miles south of Tucson. Natural vegetation varies from desert shrub, dominated by creosotebush and cactus at elevations of 3000 feet to semidesert grassland at 4000 feet characterized by numerous species of grama and three-awn grasses. Precipitation increases with elevation from approximately 12 inches at 3000 feet to 18 inches at 4000 feet. More than 90 percent of the forage production comes from perennial grasses whose main growing period coincides with summer rains of July, August, and September. Certain annuals mainly introduced Mediterranean species, mature as a result of winter rainfall, but these provide only a limited and undependable supply of forage.

Fire as a Means of Controlling Velvet Mesquite, Burroweed, and Cholla on Southern Arizona Ranges.

Abstract: A THOROUGH study needs to be made of the possibility of controlling undesirable shrubs or trees by fire on southern Arizona ranges. Other control methods, even if effective, are generally so costly as to prevent their general adoption on low-value range. Yet, it is on these low-value ranges that control is frequently most urgently needed. It has been known for many years that certain shrubs are readily killed by fire while others are very difficult to eradicate in this way (1, 6). Many observers of range conditions in the Southwest and elsewhere have suggested the use of fire as a tool to control undesirable trees and shrubs (1, 3, 6, 7). In 1907, Thornber (7) noted that when an area supporting burroweed (Aplopappus tenuisectus) was burned, all of the plants were killed, even when only partly charred. Such shrubs as catclaw (Acacia greggii), creosote bush (Larrea tridentata), Mormon tea (Ephedra trifurca), velvet mesquite (Prosopis velutina), and graythorn (Condalia lycioides), were also killed. Thornber, in 1910 (8), again reported on burning as a means of shrub control. He stated that burroweed, creosote bush, Mormon tea, and hackberry could be killed at very small expense by burning during the dry foresummer, i.e., May to June, inclusive. He noted further that charred stumps, occurring on certain areas, were an indication that fires had occurred commonly in the past and that velvet mesquite, formerly held in check by occasional fires, was at that time spreading. In the same year Griffiths (3) noted that areas formerly grass covered on the Santa Rita Experimental Range, by 1910 supported an abundant growth of young velvet mesquite and other shrubs. During the seven years that he had observed the area he noted a very definite increase in both shrubs and mesquite. He says in this connection: "The probability is that neither protection nor heavy grazing has much to do with the increase of shrubs here, but that it is primarily the direct result of the prevention of fires.-The prediction is ventured that the time is coming when these foothill grassy areas, which now have only an occasional small shrub, will be as shrubby as the deserts and lower foothills below them, if not more so". He continues with the thought that although mesquite may have been spread to some extent on the Santa Rita Experimental Range by grazing animals, its increase was more probably due to grazing that removed the combustible ground cover, thus preventing fires. Griffiths concluded that before the area was grazed by domestic stock it probably produced more grass than in 1910 and that it was formerly burned at rather frequent intervals. In his opinion this burning had little effect on the grasses but almost entirely prevented establishment of undesirable shrubs. Bec8use of the slow growth rate of the shrubs he felt that they could be controlled by fires occurring only once in ten years. He believed also that were it not for recurrent fires the then grass-covered mesas would have been dominated by shrubs as were the more

Field Comments on the Range Condition Method of Forage Survey.

Abstract: M ETHODS for the appraisal of natural resources normally undergo a period of testing and modification early in their development. This is a natural and healthy sign indicating improvement of a basic concept. Modifications of field techniques should come in large part from field workers. The thoughts in this paper represent conclusions about the range-condition survey method reached during the past several years while tramping the hills and mountains of Washington surveying many thousands of acres, talking with ranchers and co-workers, preparing ranch plans and analyzing and writing about the method. The ideas are presented in the hope they may be of value in further developing the range-condition survey method or at least in helping to clarify thinking about survey methods in general. Range condition, as the term is used today, commonly indicates forage production on an area expressed in terms of the amount it would produce under good management. Range condition is measured directly in terms of forage production and indirectly in pounds of meat or wool produced.

Distribution and Control of Several Woody Plants in Texas and Oklahoma.

Abstract: DURING the period that civilized man has held dominion over the Southwest, dwarf forests of invading shrubs and small trees have insidiously taken possession of millions of acres of the remaining uncultivated grassland. Acreage of mesquite alone in Texas and Oklahoma is greater than the area of the state of Wyoming. Many have been deceived into believing that trees and brush moved in like a plague or passover and killed out the grass (13), but that viewpoint is slowly dying out as the real cause of grass destruction and brush invasion is being understood. The primeval grasslands that were free of brush stayed free of brush because the dominating grasses had the strength to hold the land against invaders. When livestock crowded the ranges and ate down the best grasses first, the lower class plants which succeeded them were not strong enough to hold off the aggressive brush and trees. The original native grasses grow with trees and brush when correct grazing is practiced. On heavily grazed brush ranges, the only traces of original grasses are usually found within the thorny basal branches of brush, which guard the grasses against grazing animals. One Texas ranchman says that a sure clue to range improvement is when grazing lightens up so the good grasses can "come out of the bushes into the open". Cedar and other evergreen plants with dense horizontal spreading branches shade the ground so completely that they afford little or no sanctuary to grasses. While the good grasses may flourish in brush land, they can never reach excellent condition until the trees or shrubs are killed out. Successful removal and control of dense stands of undesirable woody vegetation gives farmers and stockmen a major opportunity to conserve water and to increase forage production. In areas where there are dense stands of useless woody vegetation more water is lost by transpiration through the leaves each year than runs off down the draws, streams and rivers (1). For the most part woody plants on the range are water hogs. Some, like mesquite, require two to four times more water to grow a pound of dry leaves than do grasses.

Methods of Determining Utilization of Range Forage

Abstract: A CCORDING to the Society of American Foresters (1944) "utilization" is the degree to which animals have removed the current growth of herbage and is expressed in percentage of the growth within reach of livestock. The units of measurement, as percentage of weight or height, are not mentioned. The concept may be applied to a single plant or species, to a group of plants or species, or to the whole of a range area. This article is primarily concerned with the measurement of utilization. However, a few comments on the interpretation and standards of proper use are given. Sustained production of forage plants is dependent for the most part on a moderate degree of cropping and trampling each year. Measurement, interpretation, and control of the use of forage plants is one of the most important phases of range management. No doubt utilization has been estimated by stock raisers since man began controlling livestock. The oldtime western stockman judged how near his feed was fully used or how many more days of grazing he could get from a particular pasture. These estimates were merely ocular and were influenced greatly by the man's judgment and experience. No doubt many of the estimates were accurate. However, lack of knowledge of how much grazing a range could withstand was a contributing factor to widespread range depletion. Probably the first organized attempt to control utilization was by U. S. Forest Service officials. They believed that 15 to 20 percent of the volume of herbage should remain if the forage production was to be maintained. In 1926, Sampson and Malmsten made the statement: "It is generally conceded that if from 10 to 25 percent of the herbage of the more important palatable species remains in the fall, proper utilization has been affected." Others applied the same percentages on a strictly height basis. Several authors in recent years (Lommasson and Jensen, 1938; Crafts, 1938; Parker and Glendening, 1942; Costello and Turner, 1944) have shown that most of the volume of grass herbage is produced in the lower few inches of the plants and that grazing to a certain percentage of the height may result in either under, proper, or over utilization depending upon the climate, site, or plant species. Some held the belief that 20 percent of the seed stalks should remain ungrazed on shortgrass ranges (Costello and Turner, 1944) and 25 per cent on southwestern ranges (Parker and Glendening, 1942a). The U. S. Forest Service in its revised codes in 1936 required that 10 to 25 percent of the palatable vegetation be left at the end of the grazing season and approximately 25 percent of the seed heads be allowed to reach maturity. A few range men thought that height and volume were analogous and that it made little difference whether the percentages referred to height or weight. This idea has proven fallacious. At first the differences between percentages of utilization and 100 were called palatability ratings. When attempts were made to standardize the percentages on a height, weight, or some other basis,

Reaction of a California Annual-plant Community to Fire.

Abstract: THE occurrence of fires on annualplant ranges of California poses a question to the range manager: How will the plant community react to burning and what will be the effects of fire on its grazing value? Hart, Guilbert, and Goss (4) investigated variations in chemical composition of forage from adjoining burned and unburned areas in an attempt to explain the preference shown by cattle, sheep, and deer for the herbage of burned-over areas. They did not find either consistent or appreciable changes in the calcium, phosphorus, or protein content of individual forage species and consequently concluded that other factors were involved in the matter of preference shown by the grazing animals. They did note that more filaree grew on the burned than unburned areas. They also noted that plants on unburned areas attained nearly twice the height of those on burned sites. Studies were made during the growing season of 1947-1948 on coastal foothill range lands near Berkeley, California, to determine the reaction of annual-plant communities to fire, particularly with respect to height growth, forage yield, and species composition. Four areas, each of which had been burned in July, 1947, were selected for study. They may be compared as follows:

Determining Forage Weight on Southern Forest Ranges.

Abstract: OPEN forests in the Louisana uplands I ) produce 2500 pounds or more of grass per acre per year (Fig. 1A). But adjacent 15-year-old plantations of pine or good stands of second-growth pine may not produce more than 250 pounds of green herbage per acre; most of it is covered by pine litter which weighs 6 to 10 tons per acre (Fig. iB). On southern forest ranges we are using actual weight of herbage as the basis for measuring forage production and ground cover. The method is simple, concrete, and well suited to conditions on the ground. It is an adaptation of the weight estimate method devised by Pechanec and Pickford (5), for use in determining grazing capacity on western ranges. Their method requires actual clipping and wveighing of herbage on training plots; then weight estimates only on temporary plots to inventory range forage by species. They used plots 100 square feet in size. Our adaptation of the method aims at weight measurements of vegetation as forage, as an ecological response to forest or range management, or as fuel, according to the purpose of the study. In inventorying herbage, our procedure is to actually clip and weigh the total yield by herbage classes, while the species weight composition is estimated. In 1944, the method was tried on plots ranging from 4.4 square feet (0.0001 acre) to 100 square feet in area. Weights for the smallest plots varied too greatly to yield significant results with a reasonable number of samples. The largest plots produced more herbage than could be harvested or weighed conveniently. The size plot finally selected after much trial, error, and analysis, was 9.6 square feet in area, or a square of 3.1 feet on a side about halfway between a square yard and a square meter (1). Under average herbage conditions, this size of plot gives a reasonably low error, and only 10 to 15 plots are needed to sample a vegetation sub-type. It is about the easiest size to work with, and its area is such that when herbage is weighed in grams, the production per acre can be calculated in pounds simply by multiplying the number of grams by 10, i.e., grams-per-plot times 10 equals pounds per acre. Obviously, small amounts of grass can be weighed more easily and accurately on gram scales than on pound-ounce scales. Moreover, metric weight values are better suited for field records and initial computations. Final values are in pounds per acre. It was found that plant density cannot be used as a satisfactory measure of forage production and ground cover. A range that usually has 0.6 to 0.8 density supports less than half that cover throughout the season following a spring burn, even though weight of herbage produced may actually be greater after the burn. The equipment used in determining forage yield by clipping and weighing is a pair of sheep shears, a spring scale of 500 grams capacity, a 3.1 feet square wire frame mgde of welding rods inch in diameter, paper bags in which to weigh and keep samples, and record forms. Field procedure is to place the wire frame on the sample point and to un-

Influence of Grazing and Mulch on Forage Growth.

Abstract: IT IS well known that the degree of forage removal affects individual plants, plant succession, forage production, and modifies microclimate and soil. Some investigators have pointed to the necessity of leaving a portion of the plant ungrazed to preclude undue interference with physiological processes. Others have felt that the dead plant "litter" or mulch remaining at the end of the grazing season is of even greater importance than conservative grazing in its effect on soil structure, organic content, soil temperature, moisture, and erosion, and thus upon the growing plants (2, 5, 10, 11). While mulch has long been recognized as an important element in range health, specific studies regarding its role have been undertaken rather recently (7, 8). Beutner and Anderson have shown that striking increases in forage production result from rather heavy mulches on semi-desert soils (1). Larson and Whitman have indicated a close relationship between litter accumulation and degree of forage removal (9). To investigate some of these relationships and, particularly, the effects of protection and organic mulch on forage production, plot studies were begun in 1941. The study area is located on the North Fork of Little Thompson River, nine miles east of the Town of Estes Park, Colorado, on the Roosevelt National Forest. At the outset, the study was intended to measure the relative rates of recovery of an overgrazed range under protection and under moderate grazing. As the study progressed, certain aspects of spring and summer forage growth became evident, and the apparent effect of mulch accumulation led to the addition of a mulch study.

Machinery for Seedbed Preparation and Seeding on Southwestern Ranges.

Abstract: P ROPER seedbed preparation is one of the requirements for successful reseeding. In semi-arid areas, like the Southwest , this preparation must provide for moisture conservation and soil compaction around the planted seeds. A method of seedbed preparation and planting incorporating these conditions is essential for best results in reseeding. Trials with contour furrowing failed under range conditions because of the difficulty of keeping the furrows exactly on the contour. Water runs to the lower places resulting in spotted stands of grass. Accelerated gully erosion often results from such concentration of run-off. The defects were largely corrected by placing interruptions in the contour furrows. The interruptions served as water storage basins, but they were too difficult and costly to construct. It was found that packing or firming the soil after the seed had been broadcast over the storage basins resulted in more uniform stands of grass. Benefits obtained by firming the soil led to development of the cultipacker-seeder (2). This consisted of a tandem cultipacker with seed hoppers mounted on the frame in such a way as to allow seed to drop between the two sets of wheels. When the cultipacker-seeder was run over the interrupted contour furrows it formed a desirable combination of water storage and firm seedbed. It was noted &hat a superior “catch” of grass was usually obtained in the loose soil that had been thrown out on the undisturbed soil at the edges of the furrows. When loose soil is thrown over a firm, undisturbed soil, water infiltration is increased, while simultaneously the firm soil holds the moisture in close proximity to the seed, thus making ideal conditions for seed germination and seedling establishment. Following this demonstration a search was made for machinery which would make a series of short furrows or pits and at the same time leave a considerable portion of the seedbed area undisturbed. The eccentric one-way disk as used by Barnes and Nelson (1) for renovation of blue grama grass sod in Wyoming appeared to most nearly fulfill the requirements of partial soil disturbance and water storage. With this in mind, a Wheatland one-way plow was equipped with eccentric disks and the cultipackerseeder attached behind. The machine was set up so that every other disk was eccentric with a 3 turn lag. The eccentric disks were two inches larger in diameter than the regular disks and the gang bolt holes were two inches off center. !This machinery was tested on the San Simon Land Utilization Project in a limited way in the summer of 1946 with fgir results. In 1947, further trials were made and the machinery was modified to the extent that all regular disks were removed and replaced with spacing washers to prevent. soil disturbance between the pits, thus producing the desirable condition of loose soil thrown over undisturbed soil.

Range Reseeding in Texas and Oklahoma

Abstract: A BOUT 7,000,OOO acres of eroded and depleted cropland in Texas and Oklahoma should be returned to permanent grass if erosion is to be controlled and the land made safely and permanently productive. In addition, there are about 14,000,OOO other acres of depleted grazing land with few if any desirable grasses remaining. This land too needs to be seeded or overseeded if it is to provide an economic return within the next several decades. To revegetate this vast acreage a huge quantity of seed is required. Many commercial dealers are supplying seed, but to date they have not been able to meet the demand. During the past year, about 3,512,OOO pounds of seed of native tall and mid grasses were harvested in northeastern Oklahoma by the Soil Conservation Service, soil conservation. districts and district cooperators. The harvest was made up of big bluestem, little bluestem, Indiangrass, sand bluestem, sideoats grama, sand lovegrass, switchgrass, blue grama, hairy grama, Texas bluegrass and Canada wildrye. As a result of this big harvest more acres have been seeded in Texas and Oklahoma to these good grasses than ever before. Conditions leading to the big Oklahoma seed harvest were watched carefully. Soil Conservation Service technicians in the field and from regional headquarters searching for seed-producing areas noted the favorable rains received in northeast Oklahoma during the normally hot, dry summer months. By mid-September it was evident that a bumper seed crop was assured. Arrangements were made for dozens of 12and 14-foot combines from

Spraying 2,4-D by Airplane on Sand Sagebrush and Other Plants of the Southern Great Plains.

Abstract: EXXTENSIVE tests were made in May 1947 and 1948 of the airplane application of 2, 4-D (2 ,4-dichlorophenoxyacetic acid) on sagebrush infested rangeland near the U. S. Southern Great Plains Field Station, Woodward, Oklahoma. These studies followed successful trials of hand spraying 2, 4-D on rod-square plots of sand sagebrush (Artemisia filifolia Torr.) in May, 1946. The testing of chemicals was started after extensive studies by the Station since 1937 had shown conclusively that eradication of sand sagebrush by mowing is an extremely effective range improvement practice. Studies of vegetation and grazing tests during the past 10 years have shown that removal of sand sagebrush by mowing in two successive years during June increased grass density 90 percent, carrying capacity 45 percent, gain per head 14 percent, and gain per acre 78 percent, as published in semi-annual progress reports of the Station and elsewhere (2). Although mowing was highly effective, it was too slow and costly to be widely used on large tracts of low-priced rangeland. The new chemical 2,4-D sprayed by airplane promised to overcome both of these important objections. The results reported herein are based on investigations conducted by the Division of Forage Crops and Diseases, Bureau of Plant Industry, Soils, and Agricultural Engineering, and the Bureau of Animal Industry, Agricultural Research Administration, U. S. Department of Agriculture, in cooperation with the Oklahoma Agricultural Experiment Station. In this study, the authors are indebted to J. R. Harlan, Bureau of Plant Industry, who actively participated in all phases of the tests in 1947; to A. L. Brown, formerly of the same agency, who was in charge of the spraying work in 1948; to J. E. Webster and V. G. Heller, Oklahoma Agricultural Experiment Station for conducting root reserve studies of the shrubs; and to W. H. Black, Bureau of Animal Industry, for cooperation in the grazing studies.

Getting Better Records of Vegetation Changes with the Line Interception Method.

Abstract: BASICALLY the line interception method is a means of determining areas by the measurement of line segments. It has been adapted and applied to range work by several men since about 1937 (1). In the opinion of the writer, it is a very useful range technique. It is highly adaptable and in combination with other methods can be used to measure vegetation factors like density, composition, yield, utilization, vigor and reproduction; and soil factors like erosion, bare soil, rock, and litter cover. The line plot is an efficient sampling unit; it is easily established and quickly measured. The line interception method has been described in detail by Canfield (1). The purpose of this paper is to point out a few ways in which the method can be employed more effectively in measuring changes in range vegetation. Particular attention is given to ways of increasing the accuracy of the method and of using the method to determine vegetation yield. The remarks are based on experiences with the method in pine timber, sagebrush, and meadow types in northeastern California and apply principally to bunchgrass types.

Control of Noxious Plants in a Range Management Program.

Abstract: DLANTS which are undesirable in the light of best land use are called "noxious." On range lands a noxious plant may be one which competes with the growth of desirable species and reduces grazing capacity or it may be actually poisonous to livestock, or its presence may increase handling costs. It is the purpose of this paper to point out the place of noxious plant control in a management program. Noxious plants are an ever-increasing threat to the welfare and permanence of the western livestock industry. Some people contend that since settlement of the West there has been no significant change in the vegetation. This viewpoint is contrary to the facts. It is true that large areas of grassland, brush, and timberlands in their grosser aspects are still much the same as they have always been. But closer examination even of these types will often reveal changes that have been brought about largely by noxious plant invasions. These changes are reflected over extensive areas mainly in poor productivity and accelerated erosion rates. To avoid controversy, let us look at the lands where the evidence provided by historical accounts, eyewitness descriptions of early pioneers, and retraceable early day photographs is hard to refute (1, 6, 7). In the Southwest, mesquite alone now covers some 60 million acres representing a twofold increase over its original distribution 100 years ago. The 30-million-acre increase has been largely at the expense of open grasslands. Juniper in this region has likewise encroached over additional millions of acres. In the Intermountain States and the Northwest big sagebrush is found on some 95 million acres-much of this has always been sagebrush but in the original stands it has greatly thickened and in addition has spread into some 7 to 10 million acres of higher mountain country where it was formerly a rarity. In the same region, low-value cheatgrass has replaced the more useful bunchgrass species on several million acres-and still is on the march. In California, the 11 million acres of chaparral represent a sizable expansion in brush and this largely at the expense of grassland and conifer forest types. In this State, too, there are nearly 8 million acres of woodland-grass, over much of which brush is also spreading or increasing in density. Poisonous St. Johnswort or Klamath weed, a native of Europe, has infested several hundred thousand acres of choice range in California and is still on the increase. Here and there, throughout the West, are literally dozens of other undesirable plants whose presence on the range constitute local but still important problems in range improvem-ent-for example, bitterweed in Texas, snakeweed in the Southwest, sneezeweed in Colorado, tarweed and Wyethia in the Mountain States, and pricklypear on the Great Plains. That there has been a marked change in plant cover in the West is apparent. Reduced economic returns as a result of these changes must be great. For example, the total loss from mesquite and

Conservation of the Western Range.

Abstract: 0 NLY five per cent of the more than three-fourths billion acres in the eleven western states is used for crops. About 90 per cent of this extensive land area is usable mainly for grazing purposes, and livestock production is the basic industry in the 200 counties of these range states. The eleven western states contain more than half of the United States’ total sheep, and more than a sixth of all the cattle and calves, including dairy cattle and calves, of the country. Ranch units in western regions are necessarily relatively large, with a resulting sparse population and high per capita costs of schools, roads, communications, and related services. Ranching is characterized by relatively slow turnover, and the ranch directly supplies very little of the total living of the ranch family, with the result that this high degfee of commercialization means ranchers are particularly affected by price fluctuations.