Idaho Administrative Code
Title IDAPA 20 - Lands, Department of
Rule 20.02.01 - RULES PERTAINING TO THE IDAHO FOREST PRACTICES ACT
Section 20.02.01.030 - TIMBER HARVESTING

Universal Citation: ID Admin Code 20.02.01.030

Current through August 31, 2023

01. Purpose. Harvesting of forest tree species is a part of forest management. This is how wood for human use is obtained and how forests are established and tended. During harvesting operations there will be a temporary disturbance to the forest environment. These rules establish minimum standards for forest practices that will maintain the productivity of the forest land, minimize soil and debris entering streams, and protect wildlife and fish habitat. (3-31-22)

02. Quality of Residual Stocking. Reforestation is required if harvesting reduces stocking of acceptable trees below minimums of Subsection 050.04. (3-31-22)

03. Soil Protection. For each harvesting operation, operators should select the logging method and type of equipment adapted to the given slope, landscape and soil properties in order to minimize soil erosion. (3-31-22)

a. An operation that uses ground-based equipment must not be conducted if it will cause rutting, deep soil disturbance, or accelerated erosion. On slopes exceeding forty-five percent (45%) gradient and which are immediately adjacent to a Class I or II stream, ground-based equipment, except for traction-assisted harvesting equipment, must not be used without an approved variance. Where slopes in the area to be logged exceed forty-five percent (45%) gradient, the operator, landowner or timber owner must notify the Department of these steep slopes upon filing the notification as provided for in Subsection 020.05. (3-31-22)

b. The grade of constructed skid trails on geologically unstable, saturated, or highly erodible or easily compacted soils is limited to a maximum of thirty percent (30%). (3-31-22)

c. In accordance with appropriate silvicultural prescriptions, keep skid trails to the minimum feasible width and number. Limit tractors used for skidding to that size appropriate for the job. (3-31-22)

d. Uphill cable yarding is preferred. When downhill yarding, take reasonable care to lift the leading end of the log to minimize downhill movement of slash and soils. (3-31-22)

04. Location of Landings, Skid Trails, and Fire Trails. Locate landings, skid trails, and fire trails on stable areas to prevent the risk of material entering streams. (3-31-22)

a. Locate all new or reconstructed landings, skid trails, and fire trails on stable areas outside all SPZs. Locate fire and skid trails where sidecasting is held to a minimum. (3-31-22)

b. Landing size is limited to that necessary for safe economical operation. (3-31-22)

c. To prevent landslides, fill material used in landing construction must be free of loose stumps and excessive accumulations of slash. On slopes where sidecasting is necessary, stabilize landings by seeding, compacting, riprapping, benching, mulching or other suitable means. (3-31-22)

05. Drainage Systems. Provide and maintain a drainage system for each landing, skid trail or fire trail that will control the dispersal of surface water to minimize erosion. (3-31-22)

a. Stabilize skid trails and fire trails whenever they are subject to erosion, by water-barring, crossdraining, out-sloping, scarifying, seeding or other suitable means. Keep this work current to prevent erosion prior to seasonal runoff. (3-31-22)

b. Reshape landings as needed to facilitate drainage prior to seasonal runoff. Stabilize all landings by establishing ground cover or other means within one (1) year after harvesting is completed. (3-31-22)

06. Treatment of Waste Materials. Leave or place all debris, overburden, and other waste material associated with harvesting in a way that prevents their entry into streams. (3-31-22)

a. Fell, buck, and limb trees, whenever possible, so that the tree or any tree parts fall away from Class I streams. Continuously remove slash that enters Class I streams because of harvesting operations. Continuously remove other debris that enters Class I streams because of harvesting operations whenever there is a potential for stream blockage or if the stream has the ability for transporting such debris. Place removed material five (5) feet slope distance above the ordinary high water mark. (3-31-22)

b. Remove slash and other debris that enters Class II streams whenever there is a potential for stream blockage or if the stream has the ability for transporting the debris immediately following skidding and place removed material above the ordinary high water mark or otherwise treat as prescribed by the Department. No formal variance is required. (3-31-22)

c. Deposit waste material from construction or maintenance of landings and skid and fire trails in geologically stable locations outside of the appropriate SPZ. (3-31-22)

07. Stream Protection. During and after forest practice operations, protect stream beds and streamside vegetation to provide the most natural condition possible to maintain water quality and aquatic habitat. (3-31-22)

a. Lakes require an approved site-specific riparian management prescription prior to conducting forest practices within the SPZ. (3-31-22)

b. Prior to conducting forest practice operations that cross streams using ground-based equipment, install temporary or permanent structures adequate to carry stream flow; skidding or forwarding directly in or through streams or fords is not permitted. Minimize the number of stream crossings and make direct approaches to minimize ground disturbance in the SPZ. Remove all temporary crossings immediately after use and, where applicable, crossdrain the approaches. (Construction of hydraulic structures in stream channels is regulated by the Stream Channel Protection Act - Title 42, Chapter 38, Idaho Code, and Paragraphs 040.02.e. and 040.02.g.). (3-31-22)

c. Operation of ground-based equipment is not allowed within the SPZ except at approaches to stream crossings. (3-31-22)

d. When cable yarding is necessary, across or inside the SPZs, it must be done in a way that minimizes stream bank vegetation and channel disturbance. (3-31-22)

e. Provide for LOD, shading, soil stabilization, wildlife cover and water filtering effects of vegetation along streams. (3-31-22)
i. Leave shrubs, grasses, and rocks wherever they afford shade over a stream or maintain the integrity of the soil near a stream. Landowners are strongly encouraged to leave all trees immediately adjacent to streams. (3-31-22)

ii. During commercial harvest within Class I SPZs, retain the following weighted tree count per one-hundred (100) linear feet of stream: (3-31-22)
(1) Fifty-seven (57) north of the Clearwater/Lochsa Rivers; (3-31-22)

(2) Forty-nine (49) between the Clearwater/Lochsa and Salmon Rivers; (3-31-22)

(3) Forty-one (41) south of the Salmon River; and (3-31-22)

(4) Thirty-seven (37) in drier forests with SPZs dominated by Douglas-fir and ponderosa pine. (3-31-22)

(5) At least four (4) of the above weighted tree count must be retained in the outer twenty-five feet (25') of the SPZ. (3-31-22)

iii. Calculate weighted tree count by multiplying the number of live conifers and hardwoods present in each diameter range by the weight below and then sum the results.

Diameter Range (inches)

4-11.9"

12-19.9"

20-27.9"

28-35.9"

[GREATER THAN EQUAL TO]36"

Weight

1

3

5

8

11

(3-31-22)

iv. Prior to and during harvest, cutting in any part of a given one hundred foot (100') Class I SPZ segment is only allowed if the weighted tree count in the inner fifty feet (50') of that segment is above: thirty-three (33) north of the Clearwater/Lochsa Rivers, twenty-eight (28) between the Clearwater/Lochsa and Salmon Rivers, twenty-three (23) South of the Salmon River, and twenty-one (21) in drier forests with SPZs dominated by Douglas-fir and ponderosa pine. Note that the combination of minimum values for the inner fifty feet (50') and outer twenty-five feet (25') do not meet the minimum for the SPZ segment; additional trees must be left in one or both areas to meet the rule. (3-31-22)

v. To protect filtering and shade effects of streamside vegetation adjacent to all Class II streams following harvesting and hazard management activities, retain live trees or establish new trees within thirty (30) feet on each side of the streams' ordinary high water mark to comply with the minimum stocking standards expressed in Subsection 050.04. (3-31-22)

vi. During harvesting, carefully remove timber from the SPZ in such a way that LOD, shading and filtering effects are maintained and protected. When portions of harvested or naturally fallen trees land in or over a Class I stream, leave the portion consistent with the LOD definition of Subsection 010.28. When salvaging uprooted trees, leaving the section with the root ball attached is preferred. (3-31-22)

vii. During harvesting operations, portions of felled or bucked trees not meeting the LOD definition must be removed, consistent with the slash removal requirements of Subsection 030.06. (3-31-22)

viii. To obtain a variance from the tree retention requirements, the operator must develop a site-specific riparian management prescription and submit it to the Department for approval. The prescription should consider stream characteristics and the need for LOD, stream shade and wildlife cover which will achieve the objective of these rules. (3-31-22)

ix. Stream width will be measured as average between ordinary high water marks. (3-31-22)

f. Limit direct ignition of prescribed burns to hand piles within SPZs; all other direct ignitions must occur outside of SPZs, so a backing (cooler) fire will more likely occur within the SPZ. (3-31-22)
i. Hand piles must be at least five (5) feet from the ordinary high water mark of streams. (3-31-22)

ii. No mechanical piling of slash or natural forest fuels is allowed in an SPZ (an exception is filter windrows for erosion control which must not be ignited). (3-31-22)

08. Maintenance of Productivity and Related Values. Design harvesting practices to assure the continuous growing and harvesting of forest tree species by suitable economic means and to protect soil, air, water, and wildlife resources. (3-31-22)

a. Where major scenic attractions, highways, recreation areas or other high-use areas are located within or traverse forest land, give special consideration to scenic values by prompt cleanup and regeneration. (3-31-22)

b. Give special consideration to preserving any critical aquatic or wildlife habitat, including snags, especially within SPZs. Wherever practical, preserve fruit, nut, and berry producing trees and shrubs. (3-31-22)

c. Avoid conducting operations along or through bogs, swamps, wet meadows, springs, seeps, wet draws or other locations where the presence of water is indicated by associated vegetation; temporary crossings can be used as referred to in Paragraph 030.07.b. Protect soil and vegetation from disturbance which would cause adverse effects on water quality, quantity and wildlife and aquatic habitat. (3-31-22)

d. Harvesting operations within a single ownership, in which essentially all trees have been removed in one operation, must be planned so that adequate wildlife escape cover (e.g., topography, vegetation, SPZs, etc.) is available within one-quarter (1/4) mile. (3-31-22)

Disclaimer: These regulations may not be the most recent version. Idaho may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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