Initial Development of Surface Fuel Models for The Netherlands

Estimating the spread of wildland fire is growing concern in the Netherlands, where fire events at the wildland urban interface is a growing concern with a changing climate. A multi-year project was initiated in 2012 to obtain field-based fuel measurements to be used to estimate wildland fire spread for surface fire. The overall objective was to develop either custom fuel models or utilize existing Northern American fuel models to fuel conditions in some of the hazardous vegetation in the Netherlands. Over a four-year period, 96 plots were established, a wide variety of fuel parameters measured, and ANOVA (p ≤ 0.1) and Duncan’s MRT used to place these into 56 different vegetation communities. Following multiple permutations in Behaveplus, the 56 communities were consolidated into 28 different fuel models. It was then attempted to use these fuel models as input variables in a Dutch-developed wildland fire spread model. Some fuel models produced similar fire spread, and since they were within relatively similar communities, were combined, resulting in 21 working fuel models. The results of this project will provide land managers, fire brigades and landowners more accurate wildland fire spread estimations, improving safety of the public in this densely populated country. The results of this project will contribute to more accurate and detailed calculations of the NBVM (Dutch wildfire spreadmodel). The NBVM will provide necessary information, to be able to reduce the risk on uncontrollable wildfires, via wildfire prevention measurements and during an incident, to support decision making

Forage Yields in Turkey Hill Wilderness in East Texas for White-tailed Deer

Wilderness areas are often considered quality areas where natural processes occur without human activity. It is often assumed that these unmanaged areas will provide and support quality wildlife habitat. The objective of this study was to evaluate the forage production and stocking potential of an unmanaged wilderness area in east Texas. Four different community types were evaluated for forage yield, forage availability, and browse utilization for white-tailed deer. Results show that although a wide range of forage yields were measured in the spring, summer forage yield did not differ among the various communities. Availability also differed between community types, but utilization within each community appears to be lower than what could be supported

Dynamic measurements of gear tooth friction and load

As part of a program to study fundamental mechanisms of gear noise, static and dynamic gear tooth strain measurements were made on the NASA gear-noise rig. Tooth-fillet strains from low-contact ratio-spur gears were recorded for 28 operating conditions. A method is introduced whereby strain gage measurements taken from both the tension and compression sides of a gear tooth can be transformed into the normal and frictional loads on the tooth. This technique was applied to both the static and dynamic strain data. The static case results showed close agreement with expected results. For the dynamic case, the normal-force computation produced very good results, but the friction results, although promising, were not as accurate. Tooth sliding friction strongly affected the signal from the strain gage on the tensionside of the tooth. The compression gage was affected by friction to a much lesser degree. The potential of the method to measure friction force was demonstrated, but further refinement will be required before this technique can be used to measure friction forces dynamically with an acceptable degree of accuracy

Effects of Prescribed Burning on Vegetation and Fuel Loading in Three East Texas State Parks

-This study was conducted to evaluate the initial effectiveness of prescribed burning in the ecological restoration of forests within selected parks in east Texas. Twenty-four permanent plots were installed to monitor fuel loads, overstory, sapling, seedling, shrub and herbaceous layers within bum and control units of Mission Tejas, Tyler and Village Creek state parks. Measurements were taken during the summers of 1999 and 2000. Prescribed burning was conducted between these sampling periods in early spring 2ooo. Results indicated that the current applications of prescribed burning do not significantly influence vegetation or fuels. Sustained drought, prior management practices and imposed local bum bans reduced the window within which prescribed bums could be applied, and limited the effectiveness of the burns

Stereo Photo Series for Estimating Natural Fuels in The Netherlands, Volume I: Veluwe Region

The photo series are collections of photos and associated field data representing a region of The Netherlands. Volume I includes vegetation types in the Veluwe Region, including Heather, Grasslands, Beech/Hardwoods, Scots Pine, and Douglas-fir. Volume 2 includes dune vegetation types on the island of Texel, plus a site on the mainland near Haarlam. For each vegetation type, sites were sampled with varying fuel loads. The description of the sites consists of a wide-angle site photo, supplemented with field data on the various fuel loads and vegetative layers. The photo series is an important ecological tool to assess landscapes by analyzing both dead and living fuels, and thereby provides real-world data to predict potential wildland fire behavior. The data collected can also be used to evaluate these same areas for animal and insect habitat, among other uses. The field protocols utilized for this study were modified from Stereo Photo Series in the United States authored by Roger Ottmar and Robert Vihnanek

Site Factors Influence on Herbaceous Understory Diversity in East Texas Pinus palustris savannas

Longleaf pine (Pinus palustris) savannas were once dominant across the southeastern U.S., including East Texas and parts of western and central Louisiana. The diverse understory associated with these historical savannas may occasionally be seen today, but not often in longleaf pine ecosystems. This project aimed to define east Texas site characteristics that are necessary to support these ecosystems with a dense and diverse herbaceous understory with little to no midstory cover. Fifty-nine plots across three study sites were established to evaluate the influence of overstory cover, basal area, aspect, elevation, and slope on the number of plant genera present. Forest structure and site characteristics had significant effects on the number of plant genera found. The number of genera increased with higher elevation and slope; as elevation increased, there was a decline in basal area and overstory cover, leading to a more diverse, understory layer. In order to re-establish and maintain a diverse, herbaceous understory in longleaf pine savannas, sites with more open canopies and on slopes with the most solar exposure should be given priority, particularly when planting desired understory species

Biomass estimations of invasives Yaupon, Chinese Privet and Chinese Tallow in east Texas Hardwood and Pine Ecosystems

Forest understory fuels can have profound effects on fire behavior and crown fire initiation. Accurate fire behavior prediction in understory fuels is an essential component for estimating fire intensity and severity during wildfire and prescribed fire events. This study focused on estimating temporal and seasonal changes in fuel loading parameters associated with the expansion of invasive yaupon (Ilex vomitoria), Chinese privet (Ligustrum sinense), and Chinese tallow (Triadica sebifera) in East Texas pine and hardwood ecosystems. Fuel loading data of invasive species infested sites indicated significant increases in understory biomass when compared to 1988 estimates, suggesting a clear need to revise regional fuel models. Multiple and simple regression biomass prediction equations were developed for all three-invasive species to facilitate fuel load estimates. These improved prediction equations will enhance fire management efforts as well as invasive species mitigation efforts in east Texas

Effect of a Prescribed Fire on Herbage Production in Southwestern Ponderosa Pine on Sedimentary Soils

An area burned by prescription in 1977 and a nearby unburned area were measured in 1974 and 1980 to determine effects of the burn on herbage and forage production. Herbage production on the burned area increased significantly in 1980 over its 1974 level, in addition to being greater than the 1980 control production. However, the proportion of forage production to total herbage production in 1980 on the burned area decreased after the burn, and was significantly less than the control area forage production. This reduction in forage production can be attributed to the increase of nonforage species, notably bracken fern. Increases in total herbage production on both burned and unburned areas between 1974 and 1980 are attributed to a number of factors, including increased soil moisture availability during the 1980 growing season which had 50 percent more precipitation than the historical average. FOREST ScI. 30:22--25

Impacts of Three Timber Stand Improvement Thinning Options on Low Quality Southern Mixed-Hardwood Stands

The impact of three thinning options (strip, single-tree selection, and strip with selection between strips) on lowquality southern mixed-hardwood stands was evaluated in northern Alabama. Although stand level comparisons showed no significant differences between options, individual dominant trees benefitted from the thinning treatments, exhibiting increased basal area growth during the period of the study. Intermediate treatments such as these thinning options may provide landowners with sufficient growth of selected high-quality trees to warrant the more intensive management activities on similar sites as utilized in this study

A comparison between theoretical prediction and experimental measurement of the dynamic behavior of spur gears

A comparison was made between computer model predictions of gear dynamics behavior and experimental results. The experimental data were derived from the NASA gear noise rig, which was used to record dynamic tooth loads and vibration. The experimental results were compared with predictions from the DSTO Aeronautical Research Laboratory's gear dynamics code for a matrix of 28 load speed points. At high torque the peak dynamic load predictions agree with the experimental results with an average error of 5 percent in the speed range 800 to 6000 rpm. Tooth separation (or bounce), which was observed in the experimental data for light torque, high speed conditions, was simulated by the computer model. The model was also successful in simulating the degree of load sharing between gear teeth in the multiple tooth contact region