how to calculate tons/acre course woody debris

You then assign a weight to each piece of wood according to its diameter (see Table 2). Adding those weights together estimates the tons of coarse woody debris per acre for that transect. Anywhere from 1-3 randomly placed transects per acre are then averaged together to estimate tons of debris per acre for the site.

Full Answer

How do you measure tons per acre of debris?

Therefore the New generic coarse woody debris (dbh-based) volume model: Ln(vol) = -2.2845 + 2.0349*Ln(dbh) + 0.6594*Ln(length) (with dbh in cm, length in m and volume in dm3) 10 Alterra-rapport 1257 is selected as the most accurate and generally applicable cwd volume model, producing estimates with a goodness of fit of 98%.

How much woody debris do I need per acre?

weights together estimates the tons of coarse woody debris per acre for that transect. Anywhere from 1-3 randomly placed transects per acre are then averaged together to estimate tons of debris per acre for the site. To be precise, these numbers must also include a slope correction, but as long as the slope isn’t more

How do you convert tons to cubic yards of debris?

The method is rapid and easy to use and can be applied to naturally fallen debris and to slash. The method involves counting downed woody pieces that intersect vertical sampling planes and measuring the diameters of pieces larger than 3 inches in diameter. The piece counts and diameters permit calcu- lation of tons per acre.

How do you measure tons per acre of wood?

FEMA DEBRIS ESTIMATING FIELD GUIDE CONTENTS Introduction 1 Debris Estimating Considerations 4 ... calculator, sketch pad and note . FEMA DEBRIS ESTIMATING FIELD GUIDE 7 paper, maps, GPS unit, laser rangefinder, ... • One acre of debris 10 feet high converts to 16,133 CY 43,560 SF x 10 FT = 16,133 CY 27

How long does it take to measure downed debris?

The inventory procedures are rapid and easy to . use. For average amounts of downed debris, about 5 to 6 minutes per sample point are required for the measurements. More time is usually spent in traveling and locating sample points than in making the measurements.

How many points should be used for downed material?

Areas larger than approximately 50 acres that contain a high diversity in amount and distribution of downed material should be sampled with more than 20 points. If material larger than 3 inches in diameter is scanty or unevenly distributed, the longer sampling planes in the tabulation should be used.

Why are dead branches omitted from trees?

Dead branches attached to boles of standing trees are omitted because they are not downed vegetation. Consider a particle downed when it has fallen to the ground or is severed from its original source of growth. Cones, bark flakes, needles, leaves, grass, and forbs are not counted.

What size class is used for tallying intersections?

Size classes of 0 to 0.25, 0.25 to 1, and 1 to 3 inches were chosen for tallying intersections because: 1. The class intervals provide the most resolution for fine fuels and are small enough to permit precise estimates of volume. 2.

Where did James Brown get his PhD?

D. from the University of Michigan in 1968, all in forestry. From 1961 to 1965 he did research on field measurement of fuel properties and fire-danger rating systems while with the Lake States Forest Experiment Station. In 1965 he trans- ferred to the Northern Forest Fire Laboratory, Mis- soula, Montana, where he is responsible for research on the physical properties and inventory of fuel.

What is the line intersect method?

The line intersect method employs a few long sampling planes; the planar intersect method employs many small sampling planes. If debris both greater than and less than 3 or 4 inches in diameter must be inventoried, the planar intersect technique is more efficient. The planar intersect technique can also be coordinated with other measure- ments of vegetation taken on plots (for example, an inventory of timber volume) .

What is woody debris?

Coarse woody debris is typically defined as deadstanding and downed pieces larger than 3 inches indiameter ( Harmon and others 1986), which corre-sponds to the size class that defines large woody fuel.Some ecologists include woody material larger than1 inch in diameter as CWD. Coarse woody debris is animportant component in the structure and functioningof ecosystems. A dead tree, from the time it dies untilit is fully decomposed, contributes to many ecologicalprocesses as a standing snag and fallen woody mate-rial lying on and in the soil. Fire, insects, pathogens,and weather are responsible for the decomposition ofdead organic matter and the recycling of nutrients(Olson 1963; Stoszek 1988). Fire directly recycles thecarbon of living and dead vegetation. The relativeimportance of fire and biological decomposition de-pends on site and climate (Harvey 1994). In cold or dryenvironments, biological decay is limited, which al-lows accumulation of plant debris. Fire plays a majorrole in recycling organic matter in these environ-ments. Without fire in these ecosystems, nutrientsare tied up in dead woody material for a long period.Fire, insects, and diseases perform similar roles inthat they both create and consume CWD and smallerdead woody material.

What is resistance to control?

Resistance-to-control is generally viewed as an esti-mate of the suppression force required for controllinga unit of fire perimeter. Ratings may be subjective asapplied in the Photo Guide for Appraising DownedWoody Fuels in Montana Forests (Fischer 1981). Forexample, “high” resistance-to-control means “slow workfor dozers, very difficult for hand crews; hand lineholding will be difficult.” Large woody fuel loadings inthe Photo Guide ranged widely depending on size ofdowned pieces and undergrowth. Loading for a me-dium rating ranged from 14 to 50 tons per acre.The USDA Forest Service Pacific Southwest Region(1976) developed a resistance-to-control rating schemebased on difficulty of hand line construction and aninventory of downed woody fuel loadings by size classes.High and extreme resistance-to-control ratings werereached for the following loadings (tons per acre):

What is fire hazard?

Fire hazard generally refers to the difficulty ofcontrolling potential wildfire. It is commonly deter-mined by fire behavior characteristics such as rate-of-spread, intensity, torching, crowning, spotting, andfire persistence, and by resistance-to-control. In thispaper we also consider fire severity to be an element offire hazard. Fire severity refers to the effects of fire onthe ecosystem. It depends on fuel consumption andheat flux into all living components. Downward heattransfer into the soil is an important determinant offire severity (Ryan and Noste 1985). Fire intensity,largely a measure of upward heat transfer, is not areliable indicator of fire severity because it can corre-late poorly with downward heat transfer. Small andlarge downed woody fuels contribute differently to thevarious elements of fire hazard.