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Table 1 Vegetation states for the LANDFIRE biophysical setting Mediterranean California dry-mesic mixed conifer forest and woodland (LANDFIRE zone 6 model number 0610270, online at http://www.landfire.gov/national_veg_models_op2.php).

From: Corroborating Evidence of a Pre-Euro-American Low- to Moderate-Severity Fire Regime in Yellow Pine-Mixed Conifer Forests of the Sierra Nevada, California, USA

Class Development state Structure Cover (%) Height (m) Tree diameter (cm) Transition description
A Early All 0 to 100 0 to 10 <12.7 Either tree seedlings develop a nearly continuous canopy and class moves to Class B or C, or chaparral conditions may dominate. Replacement fire mean return interval (MFRI) = 50 yr, mixed fire MFRI = 200 yr. Annually, there is 0.01 probability of succeeding to Class B, and 0.005 probability of succeeding to Class C. After 50 yr, succeeds to Class B.
B Mid Closed 51 to 100 10.1 to 25 12.7 to 63.5 Replacement fire MFRI = 75 yr, 80 % of mixed fire (MFRI = 20 yr) moves area to Class C, 20 % of mixed fire stays in Class B. Surface fire MFRI = 36 yr. Insect or disease occurs 200 yr, usually with little effect, but 20 % of occurrences move the area to Class C. After 50 yr, succeeds to Class E.
C Mid Open 0 to 50 10.1 to 25 12.7 to 63.5 Replacement fire MFRI = 315 yr, 83 % of mixed fire (MFRI = 30 yr) keeps area in Class C, 17 % of mixed fire resets area to Class A. Surface fire MFRI = 15 yr. Insect or disease occurs 500 yr, usually with little effect. After 35 yr without fire, these stands move to Class B. Patches stay in Class C >100 yr.
D Late Open 0 to 50 ≥25.1 >63.5 Replacement fire MFRI >1000 yr. Mixed fire (MFRI = 30 yr) usually leaves patch in Class D, but rarely it can move to Class A. Surface fire MFRI = 11 yr maintains Class D. Insect or disease is rather rare (annual probability = 0.001). After 35 yr without fire, this class will transition to Class E.
E Late Closed 51 to 100 ≥25.1 >63.5 Replacement fire MFRI = 160 yr, 50 % of mixed fires (MFRI = 60 yr) cause no transition, but mixed fire can move area to Class A (MFRI = 70 yr), or Class D (MFRI = 330 yr). Surface fires MFRI = 50 yr. Insect or disease mean return = 250 yr, and usually has little effect on stand structure, but 25 % of the time can move area to Class D.