Build Your Own 10-Point Frame

2008

Plant canopy cover and basal area can be difficult to measure for annual grasses, diffuse open canopy desert shrubs, or any other situation where there are lots of small packages of canopy present.  Point sampling using a sharpened pin to record "hits"  or "misses"  as it is lowered to the soil surface, allows us to calculate plant cover by assuming that each "hit" is 100% cover and each "miss" is 0% cover. So, 6 hits out of 10 pins would be 60% cover. Fixing the pins into 10-point frames reduces the possibility of personal bias (prevents you from aiming for what you want to hit) while making  calculations of % cover simple. Since there are few sources of "store bought" point sampling frames, most of us make our own. Happily, it is not difficult to construct a durable aluminum 10-point frame for a reasonable cost in materials. 

 Juniper Invades - Juniper Ecology and Management

2009

Western Juniper (Juniperus occidentalis), a native semi-arid forest tree, is moving off its traditional “natural” old growth sites and displacing adjacent sagebrush grassland, mountain mahogany, and even aspen stands in the western United States. Although old growth stands are often over 200-400 years old (the oldest juniper tree found in Central Oregon is believed to be over 1600 years old!), this new reproduction has largely occurred in several waves since 1860, probably as a result of fire suppression and heavy grazing that reduced fine fuel loads present to carry fire interacting with weather cycles that favor juniper establishment.  Juniper trees initially grow slowly for a decade or so and may be fairly small and unobtrusive when young . They are easily killed by fire at this stage. Once well established, they are fierce competitors for soil water and nutrients and often begin to noticeably impacts biotic community structure and function when 35-45 years old. Juniper captured sites desertify in a very predictable sequence.  Over a period of 30-150 years,  forb canopy cover is reduced, followed by shrub canopy, and on drier sites, grass canopy may also be severely reduced or eliminated, leaving a landscape of juniper trees standing over bare unprotected soil. When it rains, water runs off quickly rather than entering the soil, often carrying surface soil with it, eroding the site and reducing stored water available for plant growth.  The earliest waves of invasion are now reaching this obviously degraded state. However, several million acres of invading juniper are still in early to intermediate stages of degradation and may be spared this fate if surviving understory vegetation is relieved from current or potential juniper competition. Reestablishment of fire through controlled burning and mechanical removal of larger trees are popular approaches, but all actions need to be tailored to the particular characteristics of the specific site.

 Forest Grazing..... Does it Compact Soils?

2009

Soil Compaction by heavy equipment working in forests is well documented and is widely accepted as being a detriment to future forest growth. It is understandable, therefore, that forest managers are concerned about potential soil compaction from livestock grazing young forests. Anything that pushes down on the soil will compact it somewhat. Livestock hoofs do potentially exert enough force to compact the soil under them. However, their weight is dispersed both downwards and sideways, resulting in less severe and shallower compaction that that of equipment wheels or tracks. Although it is easy to measure this level of compaction, it is very difficult to show that it is sufficient to reduce tree or understory plant production in grazed forests, except in very localized "sacrifice areas" or when soils are saturated with water. In some instances, moderate compaction may actually help plants by increasing soil water storage.

How to Get a Natural Resources Job.

2011

Both the public and the private  sectors offer significant employment opportunities for natural resources professionals. While the private sector includes many different types of employment, the U.S. government is probably the single biggest natural resources employer. Federal employment is overseen by the Office of Personnel Management (OPM) which sets qualification and pay standards for U.S. Government service positions. These positions are usually described by a title, OPM job series, and pay grade. For Example,  a GS7 Range Conservationist (OPM474 series) is an entry level (GS7 pay grade) range management position as described within the 474 series.  To be considered for this job, you must meet the general qualifications for the GS7 pay grade, and the more specific requirements published by OPM for the 474 job series. Failure to meet even one of the qualifications will eliminate you from consideration. So, it is always a good idea to examine the specific job requirements as early in your career as possible.  Currently available federal jobs are listed at the USA Jobs website. OPM series and their requirements are available at the OPM website.

About DoctorRange


Dr. Sharrow's pictureDr. Sharrow is Professor of Rangeland Ecology and Management at Oregon State University, USA, where he has taught undergraduate and graduate level natural resources classes for the past 31 years.

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