OAR 629-044-0250
Natural Vegetative Fuel Hazard Factor

(1)

The reference for establishing the natural vegetative fuel hazard factor shall be the “Aids to Determining Fuel Models For Estimating Fire Behavior” published by the Forest Service, USDA Intermountain Forest and Range Experiment Station in 1982 as General Technical Report INT-122.

(2)

Using the natural vegetative fuel models described in the reference set forth in subsection (1), and summarized in Table 3, divide the jurisdiction into geographic areas which best describe the natural vegetation expected to occupy sites for the next 10 to 15 years and then select the appropriate hazard value from Table 3.
TABLE 3
NATURAL VEGETATIVE FUEL HAZARD FACTOR
Natural Vegetative Fuel Description — Hazard Value
Little or no natural vegetative fuels are present. — 0.
Grass. Very little shrub or timber is present, generally less than one-third of the area. Main fuel is generally less than two feet in height. Fires are surface fires that move rapidly through cured grass and associated material. (Fuel model 1) — 3
Grass. Open shrub lands and pine stands or scrub oak stands that cover one-third to two-thirds of the area. Main fuel is generally less that two feet in height. Fires are surface fires that spread primarily through the fine herbaceous fuels, either curing or dead. (Fuel model 2) — 3.
Grass. Beach grasses, prairie grasses, marshland grasses and wild or cultivated grains that have not been harvested. Main fuel is generally less than four feet in height, but considerable variation may occur. Fires are the most intense of the grass group and display high rates of spread under the influence of wind. (Fuel model 3) — 3.
Shrubs. Stands of mature shrubs have foliage known for its flammability, such as gorse, manzanita and snowberry. Main fuel is generally six feet or more tall. Fires burn with high intensity and spread very rapidly. (Fuel model 4) — 3.
Shrubs. Young shrubs with little dead material and having foliage not known for its flammability, such as laurel, vine maple and alders. Main fuel is generally three feet tall or less. Fires are generally carried in the surface fuels and are generally not very intense. (Fuel model 5) — 1.
Shrubs. Older shrubs with foliage having a flammability less than fuel model 4, but more than fuel model 5. Widely spaced juniper and sagebrush are represented by this group. Main fuel is generally less than six feet in height. Fires will drop to the ground at low wind speeds and in stand openings. (Fuel model 6) — 2.
Timber. Areas of timber with little undergrowth and small amounts of litter buildup. Healthy stands of lodgepole pine, spruce, fir and larch are represented by this group. Fires will burn only under severe weather conditions involving high temperatures, low humidities and high winds. (Fuel model 8) — 1.
Timber. Areas of timber with more surface litter than fuel model 8. Closed stands of healthy ponderosa pine and white oak are in this fuel model. Spread of fires will be aided by rolling or blowing leaves. (Fuel model 9) — 2.
Timber. Areas of timber with heavy buildups of ground litter caused by overmaturity or natural events of wind throw or insect infestations. Fires are difficult to control due to large extent of ground fuel. (Fuel model 10) — 3.

Source: Rule 629-044-0250 — Natural Vegetative Fuel Hazard Factor, https://secure.­sos.­state.­or.­us/oard/view.­action?ruleNumber=629-044-0250.

Last Updated

Jun. 8, 2021

Rule 629-044-0250’s source at or​.us